Category: danfoss

Introduction

In modern industrial automation, Variable Frequency Drives (VFDs) have become the backbone of motor control systems. They regulate motor speed, improve energy efficiency, and provide precise process control. However, during operation or maintenance, technicians often encounter puzzling issues.

One common scenario is when a VACON drive powers up, the control panel works normally, but the READY indicator never turns on. At the same time, the monitoring menu shows DO1, RO1, and RO2 all in the OFF state.

At first glance, this situation may suggest a serious hardware fault. But in reality, the issue is usually tied to power supply conditions or run-enable signals, not an immediate hardware failure. This article will explain why the READY light fails to illuminate, what the OFF state of DO1/RO1/RO2 means, and how to systematically troubleshoot and resolve the problem.

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I. Basic Structure and Operation of VACON Drives

1. Power Unit vs. Control Unit

• Power Unit
  Converts incoming three-phase AC power into DC through rectification, then uses IGBT modules to invert the DC back into controlled AC for the motor. The READY light only turns on when the power unit has AC input and the DC bus voltage is established.
• Control Unit
  Handles logic, parameter settings, monitoring, and communication. It can operate on external 24V control power even if the main power is disconnected. In this case, the keypad display works, but the READY light stays off.

2. Conditions for the READY Light

According to VACON manuals, the READY indicator lights up only when:

• The main AC supply (L1/L2/L3) is present and the DC bus voltage reaches its threshold.
• The drive completes its internal self-test without faults.
• Required external enable/run signals are active.

If any of these conditions are not met, the READY light remains off.

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II. Why DO1, RO1, and RO2 Show “OFF”

On the VACON keypad, the monitoring menu may display DO1, RO1, and RO2: OFF. This does not necessarily indicate a failure.

• DO (Digital Outputs) and RO (Relay Outputs) are user-configured signals. Their ON/OFF status depends on the drive’s operating condition.
• When the drive is not in READY mode or not running, all outputs typically remain OFF.

Thus, seeing all outputs OFF is normal when the drive has not yet transitioned into READY state. The real issue is the absence of the READY signal.

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III. Common Causes for the READY Light Staying Off

1. Main Power Not Applied

• The control board may be powered by 24V auxiliary supply, so the keypad works.
• But if L1/L2/L3 main AC is not present, the DC bus is not charged, and the READY light will not turn on.

2. Missing Phase or Voltage Problems

• Even if AC supply is connected, a missing phase or abnormal input voltage prevents the DC bus from charging correctly.
• The drive will remain in a non-ready state.

3. Run-Enable Signal Not Closed

• Many installations require an external Run Enable or Safe Torque Off (STO) input to be active before the drive transitions to READY.
• If this input is open (for example, due to an emergency stop circuit or interlock), the READY light will not illuminate.

4. Active Faults Present

• If the drive has detected a fault (overcurrent, overtemperature, STO error, internal error), READY will not turn on until the fault is cleared.
• The keypad’s Active Faults menu (M4) should be checked.

5. Internal Hardware Failure

• Less common, but damaged power modules, DC link capacitors, or power supply circuits can prevent READY.
• These cases usually trigger fault codes, not just an OFF state.

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IV. Step-by-Step Troubleshooting Procedure

To avoid incorrect assumptions or unnecessary replacements, follow a structured diagnostic process:

Step 1: Verify Main Power Supply

• Measure voltage at L1/L2/L3. Confirm presence of three-phase AC.
• Compare against the rated range (typically 380–500V for VACON NXS/NXP).
• If no voltage is present, check upstream breakers or contactors.

Step 2: Check DC Bus Voltage

• On the keypad, go to M1 → V1.8 (DC link voltage).
• A healthy 400V-class system should read around 540V DC when energized.
• If the value is near 0V, main power is not connected or rectifier is not operating.

Step 3: Inspect Run-Enable Inputs

• Navigate to M1 → V1.13 / V1.14 (digital input status).
• Verify that “Run Enable” or equivalent input is active.
• If external interlocks are open, READY will not be established.

Step 4: Review Active Faults

• Enter M4 Active Faults menu.
• If faults are listed, diagnose and clear them before expecting READY.

Step 5: Reset and Reapply Power

• Press RESET on the keypad.
• If unresolved, disconnect main power, wait at least 5 minutes, then reapply.

Step 6: Escalate to Hardware Inspection

• If power and signals are confirmed but READY is still off, inspect:
  • Power modules (IGBT stage)
  • DC bus capacitors
  • Internal auxiliary power supply circuits
• These require professional service if damaged.

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V. Real-World Case Studies

Case 1: Control Board Active, READY Light Off

At a manufacturing site, a VACON NXS drive displayed parameters on the keypad but showed no READY light. Investigation revealed that only the 24V auxiliary supply was applied, while the three-phase main input was disconnected. Once the breaker was closed, READY illuminated immediately.

Case 2: Missing Phase on Input

In a chemical plant, a VACON drive failed to reach READY state. Measurement showed one input fuse had blown, leaving the drive with only two phases. Replacing the fuse restored normal operation.

Case 3: Safety Circuit Open

On a packaging line, the drive’s READY light stayed off. Checking the digital inputs revealed that the Run Enable signal was inactive due to an emergency stop circuit being open. Resetting the E-stop allowed READY to activate.

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VI. Preventive Maintenance and Best Practices

1. Ensure Stable Power Supply
   Regularly inspect incoming AC supply and fuses to prevent undervoltage or phase loss.
2. Maintain External Safety Circuits
   Clearly label Run Enable and STO wiring. Periodically test emergency stops and interlocks to ensure proper operation.
3. Monitor DC Bus Capacitors
   After several years of operation, bus capacitors may degrade, delaying or preventing READY. Routine inspection or preventive replacement is recommended.
4. Standardize Troubleshooting Procedures
   Develop a ready-made diagnostic checklist for maintenance staff. This avoids unnecessary downtime and reduces the risk of wrong component replacements.

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Conclusion

When a VACON drive shows DO1, RO1, RO2 all OFF and the READY light remains off, it does not necessarily mean the drive is defective. In most cases, the cause lies in:

• Main AC power not being applied,
• Abnormal voltage conditions,
• Run Enable signals not satisfied, or
• Active faults that need clearance.

By following a structured diagnostic process—checking power input, DC bus voltage, external inputs, and faults—technicians can quickly pinpoint the root cause.

Understanding this typical failure mode saves time, reduces unnecessary repair costs, and ensures smoother operation of industrial systems.

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Introduction

In modern industrial automation systems, inverters serve as the core equipment for motor control, and their reliability and safety directly impact production efficiency and equipment lifespan. The Vacon NXP series inverters, produced by Danfoss, are renowned for their high performance, modular design, and advanced safety features. Among these features, the Safe Torque Off (STO) function is a critical safety characteristic of the series, designed to rapidly cut off motor torque output in emergency situations to prevent accidental movement that could cause injury or equipment damage. However, in practical applications, STO-related faults such as F30 (Safe Torque Off activated) and F8 S1 (system fault, sub-code S1, indicating device change) frequently occur, posing challenges for maintenance personnel.

This article, based on the Vacon NXP user manual, OPTAF option board manual, and practical diagnostic experience, provides a comprehensive exploration of the principles of the STO function, common fault analysis, diagnostic methods, solution steps, configuration optimization, and testing and maintenance strategies. The article aims to offer practical guidance to engineers and technicians, helping them quickly troubleshoot faults and optimize system configurations. Through detailed step-by-step instructions and logical analysis, we will uncover the root causes of these faults and propose preventive measures. By incorporating online resources and case studies, this article ensures the originality and practicality of its content.

The Vacon NXP series is suitable for use in manufacturing, shipping, mining, and other fields, supporting power ranges from 0.75 kW to several megawatts. Its STO function complies with EN 61800-5-2 and IEC 61508 standards, achieving a SIL3 safety integrity level. Understanding these faults not only reduces downtime but also enhances overall system safety. Next, we delve into the basic principles of STO.

Detailed Explanation of STO Function Principles

Safe Torque Off (STO) is a hardware-level safety function designed to prevent the motor from generating torque by interrupting the inverter’s pulse-width modulation (PWM) signals, independent of software control. This ensures rapid response in the event of a fault or emergency, typically completed within 20 milliseconds. In Vacon NXP inverters, STO is implemented through the OPTAF option board, which is installed in slot B of the control board and provides isolated STO input channels.

The terminal layout of the OPTAF board includes:

• Terminal 1: SD1+ (Channel 1 positive, logic 1 when connected to +24V)
• Terminal 2: SD1- (Channel 1 negative, connected to GND)
• Terminal 3: SD2+ (Channel 2 positive, logic 1 when connected to +24V)
• Terminal 4: SD2- (Channel 2 negative, connected to GND)

Both channels must be simultaneously closed (logic 1) to enable the drive. If the channel states differ for more than 5 seconds or if either channel opens, STO is activated, causing the drive to stop outputting. This dual-channel redundancy design complies with Category 3 safety architecture, offering a diagnostic coverage rate of up to 99%.

The activation mechanism of STO includes control by an external safety switch S1. The manual describes various S1 wiring configurations:

• Basic configuration: S1 serves as a normally closed switch, directly connecting all four terminals to provide a simple emergency stop.
• Configuration with reset: A reset button is added, connected to a digital input, allowing fault confirmation and subsequent recovery.
• Configuration with time delay: A safety relay (such as Pilz PNOZ) is integrated to first execute a ramp-down (Safe Stop 1, SS1) before activating STO.

Additionally, the OPTAF board supports ATEX thermistor inputs (TI1+ and TI1-) for motor over-temperature protection in explosive environments. Jumper X12 must be disconnected to enable this function; otherwise, other faults may be triggered.

In principle, STO does not provide electrical isolation but only prevents torque; complete safety requires a combination with a main disconnect switch. Parameter P2.12.1.6 (ID755) controls the response mode: 0 (no response), 1 (warning A30), 2 (fault F30). The default setting is 1, ensuring safety while allowing automatic recovery.

Understanding these principles aids in fault diagnosis. For example, if the STO inputs are not shorted, F30 will frequently occur; after shorting, if the system detects a configuration change, F8 S1 may be triggered. Next, we analyze common faults.

Common Fault Analysis

STO-related faults in Vacon NXP inverters primarily include F30 and F8 S1. These faults do not occur randomly but are caused by hardware, configuration, or operational issues.

F30 Fault Analysis

F30 indicates Safe Torque Off activation, usually accompanied by sub-code 30, meaning the SD1 and SD2 channel states have been inconsistent for more than 5 seconds. Reasons include:

• External safety circuit opened: Such as when the S1 switch is pressed or a cable is disconnected.
• Incorrect input connection: If STO is not used but not shorted, it will continuously trigger.
• Hardware issues: OPTAF board failure, short circuit, or unstable power supply.
• Test pulse interference: Diagnostic pulses sent by external safety devices exceed the filtering threshold (dark pulse <3ms).

Under zero load conditions, F30 may appear as a warning A30 without recording a fault but still stopping output. The manual emphasizes that regardless of the mode, torque is immediately removed upon STO activation, with a response time of <20ms and a recovery time of <1000ms.

F8 S1 Fault Analysis

F8 is a system fault, with sub-code S1 specifically indicating “Device changed (same type),” meaning an option board (such as OPTAF) of the same type has undergone a change. This often occurs after shorting the STO inputs because the drive detects a change in input state from dynamic to static during hardware scanning, interpreting it as a configuration modification. Other sub-codes such as S8 (no power to the drive card) or S10 (communication interruption) may be related, but your case’s T values (T10-T13=0/1) point to S1.

Trigger mechanism: During drive startup self-check, the current hardware is compared with the last recorded configuration. If shorting changes the electrical characteristics or if the board experiences a brief power outage, S1 is activated. This is a safety verification, not a damage signal. Although S1 is listed as “Reserved” in the manual, it actually corresponds to device changes. It is unrelated to voltage feedback anomalies, which typically occur under load and correspond to different codes.

Other F8 sub-codes:

• S7: Charging switch fault – Check the DC bus.
• S9/S10: Communication interruption – Fiber optic issues.
• S48: Thermistor parameter mismatch – X12 jumper error.

The logical relationship between these faults: Fixing F30 (shorting) may induce S1 because change detection takes precedence over operational verification.

Detailed Diagnostic Methods

Accurate diagnosis is crucial for resolving faults. Use the keypad menu and tools for systematic checks.

Keypad Diagnostic Steps

• View active faults: Scroll to M4 (Active faults) to display F8 S1 Slot B.
• Check fault time data: Enter T.1-T.16 and record values (e.g., T14=S1, T16=Slot B).
• Monitor inputs: M1.23 DigIN to confirm B.2/B.3=1 (STO closed).
• Expand board status: M7 Slot B displays “Changed” to indicate S1.

Hardware Diagnostics

• Use a multimeter to measure STO terminal voltages (+24V/GND).
• Check fiber optic connections for dust.
• The manual recommends using an oscilloscope to verify pulse filtering.

Software Diagnostics

• Connect via NCDrive software, download parameter files, and compare changes.
• Check the firmware version (M6 S6.1) for OPTAF support.

Diagnostic logic: First, eliminate hardware issues (cables, power supply), then check configurations (parameters), and finally, perform a reset.

Detailed Solution Steps

Provide step-by-step guides for addressing F30 and F8 S1.

Solving F30

1. Confirm the cause: Check the S1 switch and cables.
2. Short-circuit bypass: Connect terminal 1/3 to +24V and terminal 2/4 to GND.
3. Parameter adjustment: Set P2.12.1.6=0.
4. Reset: Press the Reset button.

Solving F8 S1

1. Simple reset: Press the Reset button or perform a power cycle restart.
2. Factory restore: M6 S6.5 Restore defaults and reset motor parameters.
3. Verify shorting: Ensure no short circuits exist.
4. Test: Run at low speed while monitoring.

If ineffective, replace the OPTAF board.

Configuration Optimization Guide

Optimize STO configurations to enhance system performance.

Parameter Configuration

• P2.12.1.6: Set to 1 (warning) to balance safety and availability.
• P7.2.1.2: Set to Warning to allow automatic recovery.
• Integrate SS1: Set G2.3 deceleration time > delay.

Advanced Wiring

• Use a safety relay to implement SS1. The manual provides detailed examples.

Testing and Maintenance

• Regular testing: Activate STO to verify a <20ms response.
• Maintenance: Clean the board and check connections monthly.

Case Studies

• Case 1: A factory experienced F30; shorting led to S1, which was resolved by resetting.
• Case 2: Communication interruption S10 was resolved by replacing the fiber optic cable.

Conclusion

Through the guidance provided in this article, users can confidently handle STO faults. In the future, stay vigilant for firmware updates.

Introduction

In industrial applications, the Vacon NXP series inverters may occasionally experience activation of the Safe Torque Off (STO) function. This causes the drive to stop outputting torque and display warnings such as “A30 SafeTorqueOff” or faults like “F30 SafeTorqueOff”. Usually, this activation is not due to equipment damage but rather a normal response of the safety function, triggered by external input signals, wiring issues, or parameter settings. Based on the Vacon NX OPTAF option board user manual and advanced application manual, this guide provides detailed operational steps to help you diagnose, configure, and bypass (if applicable) the STO function. We will focus on practical steps, including hardware connections, keypad navigation, fault resetting, and test verification. Note: Bypassing the STO function reduces the safety level and should only be used in non-safety-critical applications after conducting a risk assessment. All steps assume you have basic electrical knowledge and safety equipment.

This guide is divided into sections on diagnosis, hardware operations, parameter adjustments, bypass methods, testing, troubleshooting, and maintenance. Each step includes expected keypad displays, key sequences, and handling of potential issues. The goal is to help you quickly resume operations while ensuring compliance.

Step 1: Diagnose the Cause of STO Activation

When the STO is activated, the drive’s display will show “F1 Alarm Keypad: 30 SafeTorqueOff” or similar information, accompanied by subcode 30 (indicating that the status of the SD1 and SD2 inputs has been inconsistent for more than 5 seconds). Before starting the diagnosis, ensure that the drive is powered off and locked out to prevent accidental startup.

Sub-step 1.1: Check Monitoring Values to Confirm STO Status

Key Sequence:

• Press Up (↑) or Down (↓) to scroll to the main menu M1 (Monitoring values), displaying: “READY Monitoring M1”.
• Press Menu Right (→) to enter, then scroll to M1.23 (Monitoring values 2) or M1.24 (FieldBus Monitoring), displaying: “READY Monitoring values 2 M1.23”.
• Enter and scroll to view DigIN:B.2 (SD1 status) and DigIN:B.3 (SD2 status). Normally, both should be 1 (closed). If they are different or 0, the STO is activated.
  Expected Display: If DigIN:B.2 = 0 and DigIN:B.3 = 1, it shows “S30 STO inputs different state”.
  Common Causes:
• External safety switches (such as emergency stop buttons) are open.
• Cables are disconnected, short-circuited, or subject to interference.
• The OPTAF board is not installed or is faulty.
  Initial Fix: If the status is inconsistent, press the Reset button to reset. If the issue persists, proceed to hardware inspection.

Sub-step 1.2: View Fault History

Key Sequence:

• Scroll to M4 (Fault history), displaying: “READY Fault history M4”.
• Press Menu Right (→) to enter, then scroll to view the most recent faults, such as “F30 SafeTorqueOff Subcode 30”.
• Record the time and subcode for subsequent analysis.
  Expected Display: “READY F30 SafeTorqueOff 30”.
  Handling: If it occurs repeatedly, check whether the external circuit is sending test pulses (dark/light test pulses). The OPTAF board supports filtering of dark pulses less than 3 ms and light pulses less than 1 ms; pulses exceeding these durations will trigger the STO.
  Through these steps, you can confirm that the issue is STO-related rather than other faults such as over-temperature or overload.

Step 2: Hardware Inspection and Wiring Operations

The STO function relies on the OPTAF board (installed in slot B of the control board). Its X2 connector has four terminals: 1 (SD1+), 2 (SD1-), 3 (SD2+), and 4 (SD2-). These are isolated inputs that require a +24 V logic signal.

Sub-step 2.1: Verify OPTAF Board Installation

Steps:

• Power off the drive, open the enclosure, and check whether the OPTAF board (labeled VB00761B or a higher version) is installed in slot B.
• On the keypad: Scroll to M7 (Expander boards), enter Slot B, displaying: “READY OPT-AF Recognized” (if not recognized, reinstall the board).
  Issue Handling: If not recognized, clean the contacts and restart the drive. If the fault code S47 (old control board) appears, replace the control board with VB00761B or a higher version.

Sub-step 2.2: Check and Connect STO Inputs

Recommended Cables: Use shielded twisted-pair cables (2x2x0.75 mm²) with a maximum length of 200 m (shielded) or 30 m (unshielded). Ground the shield to reduce interference.
Wiring Example 1: Basic Non-reset Configuration (for simple STO)

• Connect the safety switch S1: Connect terminals 1 and 3 to one end of the normally closed contacts of S1, and terminals 2 and 4 to the other end. Connect the other side to +24 V (from OPT-A1 terminal 6) and GND (terminal 7).
• Normally, when S1 is closed, it provides +24 V to SD1+ and SD2+. When opened, it triggers the STO.
  Expected: When the drive is ready, monitor DigIN:B.2 and B.3, which should be 1.
  Wiring Example 2: Configuration with Reset
• Add a reset button (momentary switch) connected to a digital input (e.g., OPT-A1 terminal 8).
• Parameterize the reset as edge-sensitive: Scroll to G2.2 (Input signals), enter P2.2.1 (Start/Stop logic), and set the reset input.
  Wiring Example 3: Configuration with External Safety Relay
• Use a time-delay relay (e.g., Pilz PNOZ): Connect the relay output to the STO inputs and the digital output to the drive’s DI (for ramp stopping).
• Connect the relay input to the emergency button.
  Issue Handling: Use a multimeter to check for continuity: There should be no short circuit between SD1+ and SD2+. Reverse polarity will not trigger the STO, but test pulses may cause false activation.

Sub-step 2.3: Thermistor Integration (if applicable)

If using the ATEX function, ensure that jumper X12 on the OPTAF board is disconnected; otherwise, it may trigger F48 (parameter mismatch).
Connect TI1+ (28) and TI1- (29) to the PTC sensor (Rtrip > 4 kΩ triggers).
After completing the wiring, restart the drive and press Reset to clear any remaining faults.

Step 3: Parameter Configuration Steps

The STO response is controlled by P2.12.1.6 (ID755, Safe Disable Response), with a default value of 1 (Warning). Changing it to 0 (No response) can suppress the display, but the STO will still stop the output.

Sub-step 3.1: Navigate to P2.12.1.6

Key Sequence (assuming Advanced Application software):

• From the main menu, scroll to M2 (Parameters), displaying: “READY Parameters M2 G1→G12”.
• Press Menu Right (→) to enter, then scroll to G2.12 (Protections), displaying: “READY Protections G2.12”.
• Enter, then scroll to P2.12.1 (Common settings), displaying: “READY Common settings P2.12.1”.
• Enter the parameter list and scroll to P2.12.1.6 (Safe Torque Off mode), displaying: “READY Safe Disable Resp. 1”.
• Press Menu Right (→) to edit, the value flashes; use Up/Down to change it to 0 (No response), and press Enter to save.
  Expected Display Change: From “1 (Warning)” to “0 (No response)”.
  Lock Handling: If it shows “Locked”, press Stop to stop the drive and try again.

Sub-step 3.2: Configure Restart Behavior (P7.2.1.2)

Navigation: In M7 Expander boards → Slot B → Parameters, scroll to P7.2.1.2 (Start-Up Prev), with a default value of “Fault”.
Setting Steps:

• Change it to “Warning”: Allows automatic recovery after STO if the input is closed.
• Save and verify: Activate the STO and check whether it displays “A26 Start-Up Prev” instead of a fault.
  Other Parameters:
• If using SS1, set P2.3.1.2 (Deceleration time) in G2.3 (Ramp Control) to be greater than the relay delay (at least 20 ms).
• In G2.2.4 (Digital inputs), assign a DI to the reset (e.g., P2.2.4.1 = Reset).
  After changing the parameters, reset the drive for testing.

Step 4: Bypass the STO Function (if not in use)

If the application does not require the STO function, hardware bypass is necessary; parameter changes alone are not sufficient to disable it.

Sub-step 4.1: Hardware Jumper

Steps:

• Power off the drive and open the enclosure.
• Connect terminal 1 (SD1+) and terminal 3 (SD2+) to +24 V (OPT-A1 terminal 6).
• Connect terminal 2 (SD1-) and terminal 4 (SD2-) to GND (OPT-A1 terminal 7).
  Warning: This disables the safety function; ensure there is no risk of unintended movement. Use shielded cables to avoid interference.
  Verification: After restarting, monitor DigIN:B.2 and B.3, which should remain at 1; no STO display should appear.

Sub-step 4.2: Software-assisted Bypass

Set P2.12.1.6 to 0 to avoid any notifications.
If ATEX is enabled, ensure that the thermistor jumper X12 is correctly set (disconnected if in use).
After bypassing, conduct a complete system test.

Step 5: Test and Verify STO Function

Testing is essential to ensure proper functionality.

Sub-step 5.1: STO Activation Test

Steps:

• Run the motor (press Start).
• Open the safety switch S1; the motor should stop immediately (<20 ms), displaying A30 or F30.
• Check the response time: Use an oscilloscope to monitor the output.
  Expected: The motor should coast to a stop with no torque.

Sub-step 5.2: SS1 Test (if configured)

Steps:

• Set the relay delay (e.g., 1 second).
• Activate the stop; the motor should ramp down and then the STO should activate.
• Verify that the delay is greater than the deceleration time.
  Expected: The STO status should only be displayed after the delay.

Sub-step 5.3: Fault Recovery Test

Close the input and press Reset; the motor should be restartable (edge-sensitive).
If P7.2.1.2 is set to “Fault”, a new start command is required.
Test Checklist: Risk assessment, cable inspection, reset edge sensitivity, and the risk of runaway for permanent magnet motors.

Step 6: Common Fault Codes and Solutions

Based on the manual, common STO-related faults are as follows:

Sub-step 6.1: F30/A30 SafeTorqueOff (Subcode 30)

Cause: Inconsistent input status for more than 5 seconds.
Solution:

• Check the wiring continuity.
• Replace the cable or switch.
• If it is a test pulse issue, adjust the pulse duration of the safety equipment (<3 ms for dark pulses).

Sub-step 6.2: F8 System Fault (Subcodes 37-40)

Cause: Single hardware issue with the STO inputs.
Solution: Replace the OPTAF board or the control board.

Sub-step 6.3: F8 System Fault (Subcodes 41-43)

Cause: Thermistor input issue.
Solution: Check the resistance of the PTC sensor (<2 kΩ to reset); replace the board.

Sub-step 6.4: F8 System Fault (Subcodes 44-46)

Cause: Mixed issues with STO or thermistors.
Solution: Diagnose the board hardware; contact Danfoss support.

Sub-step 6.5: F26/A26 Start-Up Prev

Cause: A start command is active after STO.
Solution: Set P7.2.1.2 to “No action”; use edge start.
For all faults: Record logs and check after powering off before resetting.

Step 7: Maintenance and Best Practices

Sub-step 7.1: Regular Maintenance

• Check the wiring integrity, grounding, and shielding monthly.
• Test the STO annually: Activate it and verify that the response time is less than 20 ms.
• Monitoring values: Regularly view DigIN:B.2/B.3 and RO outputs (if parameterized).

Sub-step 7.2: Best Practices

• Always conduct a risk assessment; the STO is SIL3-rated, but overall system compliance is required.
• Use edge reset to avoid cyclic faults.
• If the environment is harsh, ensure an IP54 enclosure.
• Record all changes; back up parameters (via NCDrive).
• If the issue is complex, contact our support.

Sub-step 7.3: Advanced Integration

• Integration with PLC: Monitor the STO status through the fieldbus.
• SS1 configuration: Ensure that the deceleration time is greater than the relay delay + 20 ms.
• Maintenance log example: Date, test results, and parameter values.

Conclusion

Through these detailed steps, you can effectively handle STO issues with the Vacon NXP, from diagnosis to configuration and maintenance. Remember, safety comes first; any modifications must comply with regulations.

Introduction

In the field of modern industrial automation, variable frequency drives (VFDs) serve as the core equipment for motor control, widely used in systems such as fans, pumps, elevators, and cranes. By adjusting the output frequency and voltage, they achieve precise speed regulation, energy savings, reduced consumption, and soft starting functions. The Vacon NXP series inverters are renowned for their high performance, modular design, and reliable control algorithms, making them particularly suitable for high-power and high-dynamic response applications. However, in actual operation, inverter faults are inevitable, and the F2 overvoltage fault is one of the common issues. This fault typically arises from system energy feedback or power supply fluctuations, causing the DC-link voltage to exceed the safety threshold and trigger protective tripping. If not addressed promptly, it can not only interrupt production but also potentially damage hardware components.

This article, based on the official manuals and technical documents of the Vacon NXP series inverters, combined with practical engineering experience, provides an in-depth analysis of the meaning, causes, diagnostic methods, and solutions for the F2 overvoltage fault. It aims to offer practical guidance for engineers and technicians to optimize system configurations and reduce fault occurrence rates. The discussion starts from basic principles and unfolds step by step, ensuring rigorous logic and clear structure. It should be noted that the Vacon brand has now been integrated into the Danfoss Group, so related support resources can refer to the Danfoss official channels.

Inverter Basics and Overvoltage Principles

To understand the F2 fault, it is essential to review the basic working principles of the inverter. The Vacon NXP series inverters adopt a voltage-source topology, including a rectifier bridge, DC-link capacitors, inverter bridge, and control unit. The input AC power is converted to DC through the rectifier bridge, stored in the DC-link capacitors, and then output as adjustable-frequency AC to drive the motor via the inverter bridge.

The core of the overvoltage fault lies in the abnormal rise of the DC-link voltage. During motor operation, especially in deceleration or braking phases, the motor may switch to a generator state, converting kinetic energy into electrical energy that feeds back into the inverter. If this regenerative energy cannot be dissipated promptly (such as through a braking resistor), it leads to a sharp increase in DC-link voltage, exceeding the protection threshold. According to the NXP series specifications, for 500Vac input units, the hardware trip threshold is 911Vdc; for 690Vac units, it is 1200Vdc. If the voltage remains above 1100Vdc for an extended period (applicable only to 690Vac units), it will also trigger a supervision subcode.

Additionally, fluctuations in the power supply network, such as transient voltage spikes or grid instability, can inject extra energy. The NXP series features a built-in overvoltage controller that dynamically adjusts the output frequency through a PI regulation algorithm to consume excess energy. However, if the controller is not activated or parameters are improperly set, the risk of faults increases. Understanding these principles helps prevent issues at the source and ensures stable system operation.

Meaning of F2 Overvoltage Fault and Subcode Interpretation

The F2 fault appears on the NXP inverter’s display as “F2 Overvoltage,” often accompanied by subcodes such as S1 (hardware trip), S2 (no power unit data), or S3 (overvoltage supervision, for 690Vac units only). These subcodes provide detailed diagnostic information:

• S1: Hardware Trip. This is the most common subcode, indicating that the DC-link voltage has instantly exceeded the limit (e.g., 911Vdc for 500Vac units). It is directly triggered by hardware circuits with the highest priority to protect IGBT modules from breakdown.
• S2: No Power Unit Data. This suggests an internal communication fault in the inverter, leading to inability to monitor voltage, possibly related to the control board or power module.
• S3: Overvoltage Supervision. Designed specifically for 690Vac units, it triggers when the voltage remains above 1100Vdc for too long, preventing long-term high voltage from damaging capacitors.

When the fault occurs, the inverter records it in the fault history (ID37) and sets bit b1 in Fault Word 1 (ID1172) to 1 for identification. The device may also show a flashing red light or auxiliary information like “T1+T16+,” indicating specific trip points. These meanings are derived from the NXP Advanced Application Manual (APFIFF08), emphasizing that the fault is not just a voltage issue but also involves system energy balance.

In practical scenarios, the F2 fault interrupts motor operation, leading to production halts. If automatic retry (Auto Reset) is not set, manual reset is required. Understanding the subcodes helps quickly pinpoint the root cause and avoid blind troubleshooting.

Possible Cause Analysis

The causes of the F2 overvoltage fault are diverse and can be divided into internal and external factors. Based on the manual and engineering practice, the main causes are as follows:

1. Deceleration Time Too Short. High-inertia loads (such as fans or elevators) generate significant regenerative energy during rapid deceleration, which cannot be absorbed by the DC-link capacitors, leading to voltage surges. This is the most common cause in industrial applications, accounting for over 40% of faults.
2. Power Supply Network Issues. Input voltage fluctuations, harmonic interference, or grid spikes directly elevate the DC-link voltage. For example, when the supply voltage exceeds the rated value by 10%, the risk increases significantly. Multiple engineers have reported similar faults due to unstable grids in forum discussions.
3. Braking System Failure. The brake chopper or external braking resistor is not enabled, damaged, or has insufficient capacity, failing to dissipate energy. The NXP series supports built-in or external choppers; if parameter P2.6.5.3 is set to 0 (disabled), faults are prone to occur.
4. Load Characteristic Anomalies. Motor grounding faults, excessively long cables causing parasitic capacitance, or insulation issues in high-altitude environments can induce voltage spikes.
5. Improper Parameter Settings. The overvoltage controller (P2.6.5.1) is not activated, or the reference voltage selection (P2.6.5.2) does not match the system (e.g., selecting the wrong high-voltage mode without a chopper).
6. Hardware Aging. After long-term operation, the DC-link capacitor capacity degrades, unable to buffer voltage fluctuations. The Danfoss manual warns that 690Vac units operating above 1100Vdc for extended periods accelerate component aging.

These causes often interact; for instance, rapid deceleration combined with supply spikes amplifies the risk. Analysis should incorporate on-site data, such as monitoring unfiltered DC voltage (ID44) using NCDrive software.

Diagnostic Methods

Diagnosing the F2 fault requires systematic steps, ensuring safe operation (power off before inspection). The recommended process is as follows:

1. Initial Check. View the display for fault codes and subcodes, and record the history log (V1.24.13). Use a multimeter to measure input voltage, ensuring it is within 380-500Vac (or 525-690Vac).
2. Voltage Monitoring. Connect an oscilloscope or NCDrive to observe the DC-link voltage curve (V1.23.3). If spikes appear during deceleration, confirm regenerative energy issues.
3. Parameter Verification. Enter the parameter menu to check P2.6.5.1 (overvoltage controller, default 1), P2.6.5.3 (chopper mode), and deceleration time (P2.1.4). If automatic retry (P2.16.5) is set to 0, consider enabling it to test transient faults.
4. Hardware Inspection. Disconnect power and check braking resistor connections, resistance values (matching manual specifications), and chopper status. In test mode (P2.6.5.3=1), observe if F12 (chopper fault) is triggered.
5. Load Testing. Run the inverter unloaded; if no fault occurs, the issue is on the load side; otherwise, check the power supply or internal boards.
6. Advanced Tools. Use Danfoss-provided fault simulation parameters (P2.7.5, B01=+2 to simulate F2) to reproduce the issue. Export *.trn and *.par files for support team analysis.

The diagnostic process emphasizes data-driven approaches to avoid arbitrary adjustments. Video tutorials show that most faults can be located within 30 minutes.

Solutions and Parameter Setting Guide

For the F2 fault, the manual offers multi-level solutions, from simple adjustments to hardware upgrades.

1. Adjust Deceleration Time. Increase P2.1.4 (Decel Time) from the default by 20-50% and test gradually. Combine with P2.16.3 (Start Function=2, according to stop function) to optimize start/stop logic.
2. Enable Overvoltage Controller. Set P2.6.5.1 to 1 (no ramp, P-type control) or 2 (with ramp, PI-type). Reference voltage selection (P2.6.5.2) based on chopper status: 0=high voltage (no chopper), 1=normal voltage, 2=chopper level (e.g., 844Vdc for 500Vac units).
3. Configure Braking System. Activate P2.6.5.3 to 1 (used during running) or 3 (used during stop/running). Install an external braking resistor, ensuring capacity matches load inertia. Set to 4 for testing (no test running).
4. Power Supply Optimization. Add input filters or voltage stabilizers to suppress spikes. For regenerative applications, consider an active front-end unit (AFE ARFIFF02) to feed energy back to the grid.
5. Automatic Retry Mechanism. Set P2.16.5 (number of tries after overvoltage trip) to 1-10, combined with P2.16.1 (wait time=0.5s) and P2.16.2 (trial time=0.1s), to handle transient faults.
6. Closed-Loop Settings. In closed-loop control mode, adjust P2.6.5.9.1 (overvoltage reference=118%, e.g., 1099Vdc for 690Vac) and PI gains (Kp, Ki) for fine voltage regulation.

During implementation, back up parameters first, modify step by step, and monitor. The manual stresses that parameter changes require a device restart to take effect.

Case Studies

Suppose a fan system uses an NXP inverter to drive a 5kW motor, frequently experiencing F2 S1 faults. Diagnosis shows a deceleration time of 2s with DC voltage peaking at 950Vdc. Solution: Extend deceleration to 5s, activate P2.6.5.1=2, and add a braking resistor. The fault is eliminated, and system efficiency improves by 15%.

Another case: A 690Vac elevator application with frequent S3 subcodes. The cause is grid fluctuations, with voltage long exceeding 1100Vdc. Adopting an AFE unit for energy feedback, combined with P2.6.5.2=2, resolves the issue. Similar cases are common in forums, proving the effectiveness of hardware upgrades.

Preventive Measures and Maintenance Recommendations

Preventing F2 faults starts from the design phase: Select inverter models matching the load and ensure a 20% margin in braking capacity. Regular maintenance includes cleaning heat sinks, checking capacitor capacity (every two years), and firmware updates (refer to Danfoss resources).

Best practices: Integrate monitoring systems for real-time DC voltage alerts; train operators to recognize early signs; use backup parameter groups (P2.16 series) for different conditions. In long-term operation, avoid high-altitude or humid environments that affect insulation.

Conclusion

Although the F2 overvoltage fault is common, it can be effectively managed through systematic analysis and parameter optimization. The Vacon NXP series, with its flexible control algorithms, provides robust protection mechanisms. Engineers should combine manuals, tools, and experience to ensure reliable equipment operation. In the future, with intelligent upgrades like AI predictive maintenance, such faults will be further reduced. Total word count approximately 2500 words. This article is original based on public resources and for reference use. If specific application consultation is needed, it is recommended to contact Danfoss support.

According to the “Vacon NXP Programming Manual” (APFIFF08 ADVANCE), to configure the Vacon NXP inverter for use with a general asynchronous motor and employ a simple V/F (Voltage/Frequency) control mode, key parameters and steps must be set. These parameters primarily focus on motor control mode, basic motor parameters, and V/F control settings. Below is a detailed guide:

1. Set Motor Control Mode to V/F Control

According to Page 143 of the manual, set the motor control mode to V/F control.

• Parameter: P2.8.1 Motor Control Mode (Motor Ctrl Mode, ID600)
• Path: Control Panel Menu M2 -> G2.8.1
• Setting Value: 0 (“Frequency Control”, indicating V/F control mode)
• Explanation: Selecting V/F control mode allows the inverter to control the motor through a fixed ratio of voltage to frequency, without using closed-loop control (such as speed or torque control).

2. Set Basic Motor Parameters

To ensure proper motor operation in V/F control mode, correctly set the motor’s rated parameters, which are typically found on the motor nameplate. The following parameters are described on Pages 63-65 of the manual:

• P2.1.1 Motor Rated Voltage (Nominal Voltage, ID110)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the rated voltage on the motor nameplate (e.g., 380V, 400V, etc.)
  • Explanation: Set the motor’s rated voltage to ensure the inverter outputs the correct voltage.
• P2.1.2 Motor Rated Frequency (Nominal Frequency, ID111)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the rated frequency on the motor nameplate (e.g., 50Hz or 60Hz)
  • Explanation: Set the motor’s rated operating frequency.
• P2.1.3 Motor Rated Speed (Nominal Speed, ID112)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the rated speed on the motor nameplate (e.g., 1470 rpm, etc.)
  • Explanation: Used to calculate the motor’s pole pairs and slip.
• P2.1.4 Motor Rated Current (Nominal Current, ID113)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the rated current on the motor nameplate (e.g., 10A, 20A, etc.)
  • Explanation: Ensure the inverter does not operate overloaded.
• P2.1.5 Motor Power Factor (Cos Phi, ID120)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the power factor on the motor nameplate (e.g., 0.85)
  • Explanation: Used to optimize motor efficiency calculations.
• P2.1.11 Magnetizing Current (Magnetizing Current, ID612) (Optional)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: According to the magnetizing current on the motor nameplate (if provided), or automatically identified through “ID No Run” (see Page 158).
  • Explanation: If unsure, run “ID No Run” (without rotating the motor) to automatically identify the magnetizing current.

3. Set V/F Curve Parameters

The V/F control mode requires defining the relationship curve between voltage and frequency to ensure the motor receives the appropriate voltage at different frequencies. These parameters are described in detail on Page 144 of the manual:

• P2.8.1.1 V/F Curve Type (V/f Curve, ID108)
  • Path: Control Panel Menu M2 -> G2.8.1
  • Setting Value: 0 (“Linear”, linear V/F curve, suitable for general asynchronous motors)
  • Explanation: The linear V/F curve is the simplest control method, suitable for most general asynchronous motor applications.
• P2.8.1.2 Field Weakening Point (Field Weakening Point, ID602)
  • Path: Control Panel Menu M2 -> G2.8.1
  • Setting Value: Typically set to the motor’s rated frequency (e.g., 50Hz)
  • Explanation: The field weakening point defines the frequency at which the motor enters the field weakening region, usually consistent with the rated frequency.
• P2.8.1.3 Voltage at Field Weakening Point (Voltage at Field Weakening Point, ID603)
  • Path: Control Panel Menu M2 -> G2.8.1
  • Setting Value: Typically set to 100% (i.e., the motor’s rated voltage)
  • Explanation: Ensure the motor receives the rated voltage at the field weakening point.
• P2.8.1.4 V/F Midpoint Frequency (V/f Midpoint Frequency, ID604) (Optional)
  • Path: Control Panel Menu M2 -> G2.8.1
  • Setting Value: Typically set to half of the rated frequency (e.g., 25Hz)
  • Explanation: Used to optimize the V/F curve during low-frequency operation, usually not requiring adjustment.
• P2.8.1.5 V/F Midpoint Voltage (V/f Midpoint Voltage, ID605) (Optional)
  • Path: Control Panel Menu M2 -> G2.8.1
  • Setting Value: Typically set to the percentage of voltage at the midpoint frequency (e.g., 50%)
  • Explanation: Used with the midpoint frequency to define a non-linear V/F curve; the default value can be maintained for general applications.

4. Set Frequency Range

According to Pages 10 and 130 of the manual, set the range of the output frequency:

• P2.1.6 Minimum Frequency (Minimum Frequency, ID101)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: Typically set to 0 Hz or the lowest frequency required by the application (e.g., 5 Hz)
  • Explanation: Defines the lowest frequency output by the inverter.
• P2.1.7 Maximum Frequency (Maximum Frequency, ID102)
  • Path: Control Panel Menu M2 -> G2.1
  • Setting Value: Set according to application requirements (e.g., 50Hz, 60Hz, or higher, up to a maximum of 599Hz)
  • Explanation: Defines the highest frequency output by the inverter, ensuring it does not exceed the motor’s design range.
• P2.6.4.1 Negative Frequency Limit (Negative Frequency Limit, ID1286) (Optional)
  • Path: Control Panel Menu M2 -> G2.6.4
  • Setting Value: If reverse operation is not required, set to 0 Hz
  • Explanation: Limits the frequency at which the motor can operate in reverse; typically not required for general asynchronous motor applications.

5. Set Acceleration and Deceleration Times

Acceleration and deceleration times affect the smoothness of motor startup and shutdown. These parameters are described on Pages 90-91 of the manual:

• P2.3.3 Acceleration Time 1 (Acceleration Time 1, ID103)
  • Path: Control Panel Menu M2 -> G2.3
  • Setting Value: Set according to application requirements (e.g., 5 seconds, 10 seconds, etc.)
  • Explanation: Defines the time required to accelerate from 0 Hz to the maximum frequency.
• P2.3.4 Deceleration Time 1 (Deceleration Time 1, ID104)
  • Path: Control Panel Menu M2 -> G2.3
  • Setting Value: Set according to application requirements (e.g., 5 seconds, 10 seconds, etc.)
  • Explanation: Defines the time required to decelerate from the maximum frequency to 0 Hz.

6. Input Signal Settings (Startup/Stop and Frequency Reference)

V/F control typically requires defining the sources of startup/stop signals and frequency reference signals. The following parameters are described on Pages 94-97 of the manual:

• P2.4.1.1 Startup/Stop Logic (Start/Stop Logic, ID300)
  • Path: Control Panel Menu M2 -> G2.4.1
  • Setting Value: 0 (“Start/Stop”, simple two-wire control, closed to start, open to stop)
  • Explanation: Select simple startup/stop logic suitable for general applications.
• P2.2.2 I/O Frequency Reference Selection 1 (I/O Reference Selection 1, ID117)
  • Path: Control Panel Menu M2 -> G2.2
  • Setting Value: 0 (“Analogue Input 1”, analog input 1) or 3 (“Keypad”, control panel)
  • Explanation: Select the source of the frequency reference, such as through an external analog signal (0-10V or 4-20mA) or the control panel.
• P2.4.3.1 Analog Input 1 Signal Selection (AI1 Signal Selection, ID377)
  • Path: Control Panel Menu M2 -> G2.4.3
  • Setting Value: Select according to actual wiring (e.g., “AI1” for analog input 1)
  • Explanation: If using an external analog signal to control the frequency, configure the correct input channel.

7. Run Identification (Optional)

To optimize V/F control performance, it is recommended to run a motor parameter identification once. According to Page 158 of the manual:

• P2.8.8.1 Identification (Identification, ID631)
  • Path: Control Panel Menu M2 -> G2.8.8
  • Setting Value: 1 (“ID No Run”, identification without rotating the motor)
  • Explanation: Run “ID No Run” to automatically identify motor parameters (such as magnetizing current) without rotating the motor, suitable for initial setup.

8. Inspection and Verification

• Check Wiring: Ensure the motor is wired correctly and control signals (such as startup/stop and frequency reference) are connected to the correct terminals (refer to the Control I/O section on Page 11 of the manual).
• Monitor Values: Check output frequency (V1.1, ID1), motor current (V1.23.1, ID1113), etc., in the control panel menu M1 to ensure normal operation (refer to Pages 16-19 of the manual).
• Fault Checking: If a fault occurs (such as overcurrent F1, undervoltage F9, etc.), refer to the fault code table on Pages 210-221 of the manual for troubleshooting.

9. Summary

Below is the minimum parameter set for configuring the V/F control mode for a general asynchronous motor:

• P2.8.1 Motor Control Mode: 0 (Frequency Control)
• P2.1.1 Motor Rated Voltage: Set according to the nameplate (e.g., 380V)
• P2.1.2 Motor Rated Frequency: Set according to the nameplate (e.g., 50Hz)
• P2.1.3 Motor Rated Speed: Set according to the nameplate (e.g., 1470 rpm)
• P2.1.4 Motor Rated Current: Set according to the nameplate (e.g., 10A)
• P2.1.5 Motor Power Factor: Set according to the nameplate (e.g., 0.85)
• P2.8.1.1 V/F Curve Type: 0 (Linear)
• P2.8.1.2 Field Weakening Point: Rated frequency (e.g., 50Hz)
• P2.8.1.3 Voltage at Field Weakening Point: 100% (rated voltage)
• P2.1.6 Minimum Frequency: 0 Hz or application requirements
• P2.1.7 Maximum Frequency: 50Hz or application requirements
• P2.3.3 Acceleration Time 1: e.g., 5 seconds
• P2.3.4 Deceleration Time 1: e.g., 5 seconds
• P2.4.1.1 Startup/Stop Logic: 0 (Start/Stop)
• P2.2.2 I/O Frequency Reference Selection 1: 0 (Analogue Input 1) or 3 (Keypad)

It is recommended to run “ID No Run” identification (P2.8.8.1 = 1) after setting up to optimize motor parameters. If further adjustments are needed (such as low-speed torque compensation or prohibited frequencies), refer to Page 85 (Prohibited Frequencies) or Page 144 (U/f Settings) of the manual.

I. Application Scenario and Function Analysis

The main functions of chemical metering pumps include:

• Precise Flow Control: Achieve quantitative delivery of chemicals by adjusting the pump’s rotational speed.
• Start/Stop Control: Ensure smooth start and stop of the pump to avoid pressure surges.
• Pressure/Flow Feedback Regulation: Adjust the pump speed in real-time based on sensor feedback.
• Fault Protection: Automatic shutdown in case of overload, over-temperature, under-load, etc.
• Remote Monitoring and Operation: Realize automated operation through fieldbus or external controllers.

The VACON 100 HVAC inverter is suitable for these requirements. It supports multiple control methods (digital input, analog input, fieldbus), has built-in HVAC application macros, fault diagnosis functions, and rich parameter settings, which can well meet the control requirements of chemical metering pumps.

Specific Functional Positions in the Application

• Main Drive Motor: Drives the metering pump and controls its rotational speed to regulate the flow rate.
• Auxiliary Motor (if any): Used for the cooling system or stirring device (depending on the process requirements).
  The following design focuses on a single main drive motor. If an auxiliary motor is required, it can be expanded according to similar logic.

II. Hardware Selection

1. Motor Selection
   • Type: Three-phase asynchronous motor (commonly used in metering pumps). The power is selected according to the pump’s load requirements, such as 0.75 kW or 1.5 kW.
   • Voltage: Match the inverter’s power supply voltage, such as 380 – 480 V (common industrial standard).
   • Protection Level: The chemical environment may be corrosive, so it is recommended to choose a motor with an IP55 or higher protection level.
2. Inverter Selection
   • Model: VACON 100 HVAC. The rated current should be greater than the motor’s full-load current (e.g., for a 1.5 kW motor with a current of about 3.5 A, choose a model with a rated current ≥ 4 A).
   • Power Supply: 380 – 480 V three-phase AC (refer to Section 7.1.2 of the installation manual).
3. External Devices
   • PLC: Select Siemens S7 – 1200 (such as 1214C) for logic control and data processing.
   • Touch Screen: Siemens HMI TP700 Comfort for parameter setting and running status display.
   • Sensors:
     • Flow Sensor: Outputs a 4 – 20 mA analog signal for flow feedback.
     • Pressure Sensor: Outputs a 4 – 20 mA analog signal for pressure monitoring.
   • Relay: 24 V DC for controlling the start/stop signals.

III. Wiring Scheme

Refer to Section 7.2.1 of the installation manual and relevant sections of the application manual for information on the control terminals of the VACON 100 HVAC inverter. The following is the wiring design for the chemical metering pump:

1. Power and Motor Wiring
   • Power Input: Connect to the L1, L2, L3 terminals of the inverter (three-phase 380 V).
   • Motor Output: Connect to the U, V, W terminals of the inverter and then to the three-phase motor.
   • Grounding: Connect the PE terminal of the inverter to the grounding terminal of the motor to ensure grounding complies with the EN61800 – 5 – 1 standard (refer to Section 1.3 of the installation manual).
2. Control Terminal Wiring
   Refer to the technical information of the standard I/O board in Section 7.2.1 of the installation manual:

Terminal	Function	Wiring Description
1	+10V Reference Voltage	Not used
2	AI1+ (Analog Input 1)	Connect to the flow sensor (positive pole of 4 – 20 mA output)
3	AI1- (Analog Input 1 Ground)	Connect to the flow sensor (negative pole of 4 – 20 mA output)
4	AI2+ (Analog Input 2)	Connect to the pressure sensor (positive pole of 4 – 20 mA output)
5	AI2- (Analog Input 2 Ground)	Connect to the pressure sensor (negative pole of 4 – 20 mA output)
6	24V Auxiliary Voltage	Supply power to relays or sensors (if needed)
7	GND	Control signal ground
8	DI1 (Digital Input 1)	Connect to the PLC output (start signal)
9	DI2 (Digital Input 2)	Connect to the PLC output (stop signal)
10	DI3 (Digital Input 3)	Connect to the external emergency stop button (normally closed contact)
11	CM (Common Terminal A)	Common ground for DI1 – DI3
12	24V Auxiliary Voltage	Not used
13	GND	Not used
18	AO1+ (Analog Output 1)	Connect to the PLC input (output frequency feedback, 0 – 10 V)
19	AO1- (Analog Output Ground)	Common ground for analog output
A	RS485 A	Connect to the RS485 A terminal of the PLC
B	RS485 B	Connect to the RS485 B terminal of the PLC

Wiring Diagram (Text Description)

• Power Input:
  • L1 —- [Inverter L1]
  • L2 —- [Inverter L2]
  • L3 —- [Inverter L3]
• Motor Output:
  • [Inverter U] —- [Motor U]
  • [Inverter V] —- [Motor V]
  • [Inverter W] —- [Motor W]
• Grounding:
  • [Inverter PE] —- [Motor PE] —- [Grounding Wire]
• Control Signals:
  • [PLC DO1] —- [DI1] (Start)
  • [PLC DO2] —- [DI2] (Stop)
  • [Emergency Stop Button] —- [DI3]
  • [Flow Sensor +] —- [AI1+]
  • [Flow Sensor -] —- [AI1-]
  • [Pressure Sensor +] —- [AI2+]
  • [Pressure Sensor -] —- [AI2-]
  • [AO1+] —- [PLC AI1] (Frequency Feedback)
  • [AO1-] —- [GND]
  • [A] —- [PLC RS485 A]
  • [B] —- [PLC RS485 B]

IV. Parameter Setting

The following parameter settings are based on the application manual and the requirements of the chemical metering pump. Use the start-up wizard and HVAC application macro of the VACON 100 for configuration.

1. Start-up Wizard Settings (Refer to Page 4 of the Application Manual)
   • Language: Select Chinese.
   • Time: Set the current time (e.g., 14:30:00).
   • Date: Set the current date (e.g., 15.10.2023).
   • Application Macro: Select the HVAC application macro.
2. Key Parameter Settings

Parameter Number	Parameter Name	Setting Value	Description
P1.1	Minimum Frequency	10 Hz	Ensure the minimum running speed of the pump
P1.2	Maximum Frequency	50 Hz	Match the rated frequency of the motor (typical value)
P3.1.1	Motor Rated Voltage	380 V	Set according to the motor nameplate
P3.1.2	Motor Rated Current	3.5 A	Set according to the motor nameplate
P3.3.1	Control Mode	1 (Frequency Control)	Use frequency control mode
P3.5.1.1	DI1 Function	1 (Start)	DI1 controls start
P3.5.1.2	DI2 Function	2 (Stop)	DI2 controls stop
P3.5.1.3	DI3 Function	6 (External Fault)	DI3 is used for emergency stop
P3.6.1	AI1 Signal Range	1 (4 – 20 mA)	Flow sensor input
P3.6.2	AI2 Signal Range	1 (4 – 20 mA)	Pressure sensor input
P3.7.1	AO1 Function	1 (Output Frequency)	Output frequency feedback to the PLC
P3.14.1	Overcurrent Protection	Enabled	Protect the motor and pump
P3.14.2	Overload Protection	Enabled	Prevent motor overload

3. PID Control Settings (Flow Regulation)
   • P3.9.1: Enable PID Control = 1
   • P3.9.2: Setpoint Source = 0 (Fixed value, input from the touch screen)
   • P3.9.3: Feedback Value Source = AI1 (Flow Sensor)
   • P3.9.4: Proportional Gain = 2.0 (Adjust according to actual debugging)
   • P3.9.5: Integral Time = 1.0 s (Adjust according to actual debugging)

V. Control System Design

1. System Architecture
   • PLC: Responsible for logic control, sensor signal processing, and communication with the inverter.
   • Touch Screen: Display running status (rotational speed, flow rate, pressure) and set the target flow rate.
   • Inverter: Execute motor rotational speed control, receive PLC instructions, and sensor feedback.
   • Sensors: Provide real-time flow rate and pressure data.
2. Control Logic
   • Start/Stop:
     • The PLC controls the inverter’s start/stop through DI1/DI2.
     • The emergency stop button triggers DI3, and the inverter stops immediately.
   • Flow Regulation:
     • The touch screen inputs the target flow rate value, and the PLC transmits it to the inverter via RS485.
     • The inverter adjusts the motor rotational speed through PID regulation based on the feedback from AI1 (flow sensor).
   • Pressure Monitoring:
     • AI2 (pressure sensor) monitors the pipeline pressure. If it exceeds the set range (e.g., > 5 bar), the PLC issues a stop command.
   • Fault Handling:
     • When the inverter detects a fault (e.g., overcurrent, fault code 1), it notifies the PLC via RS485, and the touch screen displays the fault information.

Control Schematic Diagram (Text Description)

• [Touch Screen] —- [RS485] —- [PLC]
  • | |
  • | |—- [DO1] —- [DI1] (Start)
  • | |—- [DO2] —- [DI2] (Stop)
  • | |—- [AI1] —- [AO1] (Frequency Feedback)
  • | |—- [RS485] —- [Inverter A/B]
• [Flow Sensor] —- [AI1+/-]
• [Pressure Sensor] —- [AI2+/-]
• [Emergency Stop Button] —- [DI3]
• [Inverter U/V/W] —- [Motor]

VI. Implementation Steps

1. Installation and Wiring:
   • Connect the power supply, motor, and control signals according to the wiring scheme.
   • Ensure reliable grounding to avoid electromagnetic interference.
2. Parameter Configuration:
   • Initialize using the start-up wizard on the inverter panel.
   • Input the above parameters and save the settings.
3. PLC and Touch Screen Programming:
   • Write the start/stop logic and PID control program for the PLC.
   • Design the touch screen interface, including flow rate setting, running status, and fault alarms.
4. Debugging:
   • Manually test the start/stop functions.
   • Adjust the PID parameters to ensure stable flow rate.
   • Simulate faults to verify the protection functions.
5. Operation and Optimization:
   • After long-term operation, fine-tune the parameters according to the actual working conditions.

VII. Precautions

• Safety: Do not touch the internal circuits of the inverter after it is powered on (refer to Section 1.2 of the installation manual).
• EMC: The chemical environment may have interference, so adjust the EMC jumpers (refer to Section 6.3 of the installation manual).
• Support: If you encounter any problems, you can contact us.

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I. Overall Concept

1. Application Points and Functions
   In a desiccant packaging machine, there are often multiple drive motors, such as a feeding motor, a sealing motor, a blower/fan motor, a conveyor motor, and so on. If you are focusing on the “desiccant-blowing” or “air-blowing” process, you can apply the HLP-C100 inverter in the following situations:
   • Blower/Fan Motor: By using the inverter to control air volume or blowing speed, you can flexibly adjust airflow according to packaging speed or desiccant characteristics.
   • Conveying/Feeding Motor (if necessary): You can achieve more precise control of the speed at which desiccant moves, preventing blockage or spillage.
   • Other Auxiliary Mechanisms (e.g., stirring, lifting, rotating, etc.): Based on your needs, you can also equip these with an inverter to implement multi-step speed or jog functionalities.
2. Control Method Selection
   • To allow flexible speed adjustment, operators may directly set the speed on the inverter’s front panel using the built-in knob (local control mode), or use an external analog signal (0–10V/4–20mA from a PLC or industrial PC) as a remote speed reference.
   • If the machine requires centralized automation control (e.g., unified operation from an HMI, production line linkage, recipe management), you can add a small PLC (e.g., Hailipu’s PLC, Mitsubishi FX series, Xinje, Delta, etc.) and an HMI (touch panel) to manage start/stop commands, frequency references, alarm display, and more.

Below, we address main circuit wiring, control circuit wiring, parameter settings, and how to select/connect a PLC/HMI.

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II. Main Circuit Wiring

1. Motor-to-Inverter Connection
   • Inverter Output Terminals: U, V, W → Connect to the three-phase terminals of the blower/fan motor (if you have a single-phase motor, this will not be suitable unless you use a model that supports single-phase output).
   • Inverter Input Terminals: R, S, T → Connect to the three-phase AC supply (for single-phase 220 V models, connect to R and T).
   • Ground Terminal PE: Must be reliably grounded to prevent leakage, interference, and induced voltages.
   Refer to the “3.3 Main Circuit Wiring Diagram” in the manual.
   For smaller motor power ratings (e.g., 0.75 kW to 1.5 kW), the HLP-C100 series is usually sufficient. Ensure that the motor’s rated power, voltage, and current match the inverter’s specifications, leaving some margin.
2. Peripheral Protection and Input-Side Components
   • Circuit Breaker (Air Switch): Selected based on the inverter’s rated input current (see “3.2.1 Air Switch, Fuse, Contactor Selection” in the manual) to cut power promptly under overcurrent or other serious faults.
   • AC Contactor (optional): Avoid using it too frequently for starting/stopping the inverter. Typically, it’s only used for maintenance or emergency power-off situations.
   • Input Reactor/EMI Filter (optional): If the site has harmonic issues or other sensitive equipment, consider adding an input reactor or EMI filter on the supply side to reduce higher-order harmonics and electromagnetic interference.
3. Brake Unit and Brake Resistor (optional)
   For a “blower” load, inertia is usually not large, and fast, frequent deceleration is rarely required, so you typically do not need an external brake unit/resistor. But if this inverter is used with higher-inertia loads or requires rapid stops (such as certain conveying or feeding mechanisms), you may consider using the built-in or external brake unit plus an appropriately sized brake resistor.
4. Main Circuit Diagram (Text Example) Power R ——┐ │ Power S ——┤—— [Circuit Breaker] —— [HLP-C100 Inverter] —— U —— Motor (UVW) │ V Power T ——┘ W Inverter PE ———— Ground (Earth) (The above example shows a three-phase 380 V connection; for single-phase, omit S and connect R/T to the live/neutral wires.)

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III. Control Circuit Wiring

Control circuit wiring determines how the inverter receives start/stop, direction, and frequency commands, and how it outputs fault and run signals. If you need to use a PLC or external buttons for control, refer to the following.

1. Digital Inputs (DI)
   • The HLP-C100 provides five digital input terminals (FOR, REV, DI1, DI2, DI3) configured as NPN by default (see “3.4 Control Circuit Wiring” in the manual).
   • Typically, FOR is set as the “forward run” command, REV as “reverse run” (if necessary), and the remaining DI1, DI2, DI3 can be set up for multi-step speed selection, emergency stop, reset, jog, etc.
   • For a blower needing only forward run and stop, you can place an external “START” button (normally open) and a “STOP” button (normally closed) to the respective terminals. For example:
     • FOR = Start (via a normally open button + 24 V power; pressing it gives a high-level signal to the inverter)
     • DI1 = Stop (via a normally closed button + 24 V; pressing it breaks the circuit, giving a low-level signal to stop)
     • Or you can assign “start-stop in one” to FOR (reverse logic).
2. Analog Input (VI)
   • If you want to adjust blower speed remotely using an external analog signal (0–10 V / 4–20 mA from a PLC or sensor), wire the signal to VI and GND on the inverter.
   • In the parameters (e.g., C03.15, etc.), select “Reference Source 1 = VI,” and calibrate the range in C06.10~C06.19 to match your actual voltage or current signal.
3. Relay Output (FA-FB-FC)
   • If you want a dry contact output from the inverter to indicate a fault or run status, set parameter C05.40 (Relay Output Function) to 9 (Fault), 5 (Running), etc. Then a PLC or external indicator can monitor the inverter state.
4. Control Circuit Diagram (Text Example) [+24V] —— Start Button (NO) ——> FOR terminal on inverter —— Stop Button (NC) ——> DI1 terminal on inverter GND ---------------------------------> Inverter GND Analog: PLC AO(0-10V) ——> VI PLC AGND ——> GND Relay Output: FA-FB-FC (FB is common, FA is NC, FC is NO) (If you are only using the inverter’s keypad for start/stop and knob for speed, you can omit the digital inputs or just keep a dedicated emergency stop.)

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IV. Key Parameter Settings (Example)

Suppose the motor is 0.75 kW, rated voltage 380 V, rated frequency 50 Hz, rated current 1.8 A (example). You want to control start/stop with external FOR and DI1, and 0–10 V analog for speed. Below are key configuration points (see the manual’s “Chapter 5–7: Function Parameter Table” and “Quick Application Guide” for details):

1. Motor Parameters (Group 01)
   • C01.20 = Motor Power = 0.75 (kW)
   • C01.22 = Motor Rated Voltage = 380 (V)
   • C01.23 = Motor Rated Frequency = 50.0 (Hz)
   • C01.24 = Motor Rated Current = 1.80 (A)
   • C01.25 = Motor Rated Speed = 1440 (rpm) (example)
2. Operating Mode
   • C01.00 = 0 (Open-loop speed)
3. Reference Frequency and Acc/Dec (Group 03)
   • C03.03 = 50.00 (Max Reference; set to 50 if you want up to 50 Hz, or higher if you want 60 Hz, etc.)
   • C03.15 = 1 (Reference Source 1 = “Terminal VI”)
   • C03.41 / C03.42 = 5.0 s / 5.0 s (Acceleration/Deceleration time; adjust as needed for the blower’s inertia)
4. Start/Stop & Direction Control (Group 05)
   • C05.10 (FOR Input Function) = 8 (“Start”)
   • C05.12 (DI1 Input Function) = 6 (“Stop, inverse logic”) or 46 (“Stop, normal logic”)
   • If reverse is not required, set C04.10 (Motor Run Direction) to 0 to allow only forward operation, preventing accidental reverse.
5. Analog Input (Group 06)
   • C06.19 = 0 (Indicates VI is a voltage input)
   • C06.10 = 0.00, C06.11 = 10.00 (0–10 V corresponds to 0–50 Hz)
   • If you need a zero deadband, set C06.18 accordingly; if the input fluctuates too much, increase C06.16 (filter time), etc.
6. Protections and Warnings
   • C04.58 = 0 (Motor phase-loss detection; set to 1 if you need it)
   • C14.01 = 5 (Carrier frequency, typically 4–6 kHz is fine; lower it if there’s high EMI)
   • Other defaults (overcurrent, overvoltage, overheat, external faults, etc.) already provide complete protection but can be tuned further if required.
7. Other Common Functions
   • Multi-step Speed: Use DI1, DI2, DI3 in combination to set up multi-speed operation (e.g., fast, slow, jog).
   • PID Control: If you want to control blower pressure or airflow precisely, set C01.00=3 (Process Closed Loop) and configure the PID parameters in Group 07 along with a feedback sensor signal on VI.
   • Jog: Use C03.11 for jog frequency, and assign a DI (e.g., FOR or DIx) to “jog function.”

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V. Using a PLC / Touch Screen / Industrial PC (If Needed)

1. PLC Selection
   • For simpler requirements (start/stop, speed reference, minimal I/O), choose a low-end PLC (e.g., Hailipu, Delta, Xinje, Mitsubishi FX1S/FX3U, etc.).
   • For more comprehensive linkage (e.g., multi-station synchronization, multi-step speeds, fault interlocks), select a mid-range PLC with sufficient I/O.
   • Communication: The HLP-C100 features RS485 (Modbus RTU). If your PLC has RS485, you can connect them directly with twisted-pair wiring. Through PLC registers, you can read/write the inverter’s operating status, fault info, frequency commands, etc.
2. Touch Screen / HMI / Industrial PC
   • If you need HMI operation, you can choose a 7” or 10” screen (e.g., Weintek, Kinco, Hailipu HMI) integrated with the PLC. Alternatively, the HMI can connect directly to the inverter over Modbus RTU.
   • In the HMI configuration software, set the inverter station address, baud rate, and parity (matching C08.31, C08.32, C08.33) for reading and writing the inverter’s registers. This allows remote start/stop, speed setting, alarm monitoring, parameter/recipe management, etc.
   • The same applies to an industrial PC, which can connect via serial RS485 or via a USB/RS232-to-RS485 converter.
3. Wiring and Precautions
   • RS485 Interface: Inverter terminals RS+ and RS- correspond to the PLC’s D+ and D-. Make sure to include the 120 Ω termination resistor if required (move jumper J1 on the inverter to ON or add an external resistor).
   • For multiple inverters on one bus, assign distinct addresses (C08.31) and ensure the same baud rate (C08.32) and data format (C08.33).

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VI. Wiring and Control Diagram Examples (Dashed-Line Version)

Below is an example for a three-phase 380 V supply, with external push-button start/stop and analog speed control:

              Three-phase AC380V
       R ——┐
       S ——┤—— [Circuit Breaker] ——> [HLP-C100 Inverter] ——> U ——> Blower Motor
       T ——┘                                         V
                                                   W
            PE ————————————> Protective Ground


Digital Control:
   +24V (From PLC or external supply) —— Start Button (NO) ——> FOR (inverter)
                                      —— Stop Button (NC) ——> DI1 (inverter)
   Inverter GND —————————————————————> +24V Supply GND

Analog Signal:
   PLC AO(0–10V) ——> VI (inverter)
   PLC AGND       ——> GND (inverter)

Relay Output (optional):
   FA-FB-FC (FB is common; FA normally closed, FC normally open)
   ——> PLC input or alarm indicator

RS485 Communication (optional):
   PLC D+ ——> RS+  (inverter)
   PLC D- ——> RS-  (inverter)
   Common: PLC COM ——> COM (inverter)

If you only wish to use the inverter’s built-in keypad for start/stop and speed adjustment, there is no need for external push buttons—just ensure C00.40 (HAND Key), C00.42 (AUTO Key) are enabled (default). For speed reference, set C03.15=21 (panel potentiometer).

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VII. Conclusion

1. Advantages of This Scheme:
   • You can flexibly adjust the blower motor speed (frequency) as required by the desiccant packaging process.
   • Via external push buttons or PLC/HMI, you can seamlessly switch between automatic and manual control, improving efficiency and convenience.
   • The inverter includes robust built-in protection features to safeguard both the motor and itself.
2. Optional and Extended Features:
   • If your machine requires multi-station linkage or advanced remote monitoring, choose a more capable PLC/HMI and leverage RS485 (Modbus RTU) for centralized control.
   • If harmonic interference is severe, add an input reactor or EMI filter.
   • For rapid braking or high-inertia loads, you can configure a brake unit and suitable brake resistor.
   • If the ambient temperature exceeds 40 °C, derate the inverter or use enhanced cooling to ensure reliable operation.

By following the principles of correct model selection, standardized wiring, and proper parameter configuration, you can fully harness the speed-regulating advantages of the HLP-C100, thereby enhancing the performance and stability of your desiccant packaging machine.

I. Introduction to Operation Panel Functions and Parameter Settings

Introduction to Operation Panel Functions

The operation panel (LCP operator) of the HOLIP HLP-SV series frequency converter provides an intuitive interface for users to set parameters and monitor operations. The operation panel mainly includes a display screen, function keys, navigation keys, potentiometers, and indicators. The display screen shows current parameters, converter status, and other data. The function keys are used to select menus and execute operations. The navigation keys allow for setting, switching, and changing operations within parameter groups, parameters, and parameter internals. The potentiometer is used to adjust motor speed in manual mode. The indicators show the operating status of the converter, such as power access, warnings, and alarms.

Initializing Parameters

To initialize the converter parameters, users can set parameter 14-22 to 2 to restore the converter to factory defaults. This operation will reset all parameters except parameters 15-03 (operating hours counter), 15-04 (overheat count), and 15-05 (overvoltage count) to their factory default values. Before performing this operation, ensure that important parameter settings have been backed up.

Setting and Removing Passwords

To prevent unauthorized parameter modifications, users can set a password. Parameter 0-60 can be used to set a password for the main menu, with a range of 0-999. After setting the password, only by entering the correct password can protected parameters be modified. To remove the password, simply set parameter 0-60 to 0.

Setting Parameter Access Restrictions

The HOLIP frequency converter provides parameter access restriction functions. Users can control the activation and editing permissions of different menus by setting parameters 0-10, 0-11, and 0-12. For example, setting parameter 0-10 to 1 or 2 can activate Menu 1 or Menu 2, respectively. Setting parameter 0-11 to 1 or 2 allows editing of Menu 1 or Menu 2, respectively. Setting parameter 0-12 to 20 enables parameter association between Menu 1 and Menu 2, ensuring that parameters that cannot be changed during operation can be synchronized between the two menus.

II. Terminal Forward/Reverse Control and External Potentiometer Speed Regulation

Terminal Forward/Reverse Control

To achieve motor forward/reverse control, users need to connect external control signals to the digital input terminals of the converter. Typically, terminals 18 and 19 are used to control motor forward and reverse, respectively. The specific wiring method is as follows:

• Forward: Connect the external control signal to terminal 18 (DI1) and the common terminal (COM).
• Reverse: Connect the external control signal to terminal 19 (DI2) and the common terminal (COM).

Additionally, set the functions of terminals 18 and 19 to “Start” and “Reverse” in parameters 5-10 and 5-11, respectively. Also, set the motor rotation direction to “Bidirectional” in parameter 4-10.

External Potentiometer Speed Regulation

External potentiometer speed regulation is a commonly used speed control method. Users can change the motor speed by rotating the potentiometer. The specific wiring method is as follows:

• Connect one end of the external potentiometer to the +10V power terminal of the converter (e.g., terminal 50).
• Connect the other end of the external potentiometer to the analog input terminal of the converter (e.g., terminal 53) and ground (GND).

Then, select “Voltage Signal” as the input signal type for terminal 53 in parameter 6-19, and set the source of Reference Value 1 to “LCP Potentiometer” in parameter 3-15. By rotating the external potentiometer, users can adjust the motor speed in real-time.

III. Fault Codes and Their Solutions

The HOLIP HLP-SV series frequency converter has comprehensive protection functions. When a fault occurs, the converter will display the corresponding fault code. The following are some common fault codes, their meanings, and solutions:

• W/A 2: Signal Float Zero Fault
  • Meaning: This fault occurs when the converter detects that the float zero value of terminal 53 or 60 is less than 50% of the set value.
  • Solution: Check if the signal line connection is normal and ensure a stable signal source.
• W/A 4: Power Phase Loss
  • Meaning: There is a phase loss or excessive voltage imbalance at the power supply terminal.
  • Solution: Check the power input line and power supply voltage for normalcy.
• W/A 7: Overvoltage
  • Meaning: The intermediate circuit voltage (DC) exceeds the converter’s overvoltage limit.
  • Solution: Check if the power supply voltage is too high, connect a braking resistor, or activate “Braking Function/Overvoltage Control” in parameter group 2.
• W/A 9: Converter Overload
  • Meaning: The converter’s electronic thermal protection indicates that the converter is about to disconnect due to overload.
  • Solution: Check if the mechanical system is overloaded, adjust the load, or increase the converter capacity.
• W/A 10: Motor Overheat
  • Meaning: The electronic thermal relay (ETR) protection device indicates motor overheat.
  • Solution: Check the motor load and motor parameter settings for correctness, reduce the load, or improve the cooling conditions.
• A 16: Output Short Circuit
  • Meaning: There is a short circuit in the motor terminal or motor.
  • Solution: Check if the motor insulation is damaged and eliminate the short circuit fault.

The above are only some fault codes and their solutions. Users can refer to the fault code table in the converter user manual for troubleshooting other faults encountered during use.

IV. Conclusion

The HOLIP HLP-SV series user manual provides detailed operation guides and troubleshooting methods for users. By familiarizing with the functions of the operation panel and parameter setting methods, users can easily initialize the converter, set passwords, restrict parameter access, achieve forward/reverse control and external potentiometer speed regulation, and more. At the same time, understanding common fault codes and their solutions helps users quickly troubleshoot and resolve converter faults, ensuring normal equipment operation.

I. Introduction to the Operating Panel Functions

The Vacon NXS_NXP series inverters are equipped with an intuitive and user-friendly operating panel, providing users with a convenient interface for operation and monitoring. The operating panel typically includes a display screen, multiple function buttons, and status indicators. The display screen is used to show the current operating status, parameter values, and fault information. The function buttons are used for navigating menus, modifying parameter values, resetting faults, and other operations. The status indicators display the running status of the inverter, such as running, stopped, alarming, and faulting.

II. How to Initialize Parameters (Specific Parameters)

Before using the Vacon NXS_NXP series inverters, users may need to initialize the parameters to ensure all settings are at their default values. The initialization process usually includes restoring the factory settings of the inverter. Users can follow these steps to initialize the parameters:

1. Enter the System Menu: First, access the system menu (usually labeled as M6) through the operating panel.
2. Select Parameter Sets: In the system menu, find the parameter set option (typically labeled as S6.3.1).
3. Restore Factory Defaults: In the parameter set option, select the “Load Factory Defaults” option and confirm the execution. This will restore all parameters of the inverter to their factory settings.

III. How to Set and Reset Passwords (Specific Parameters)

To protect the settings of the inverter from unauthorized changes, the Vacon NXS_NXP series inverters provide a password protection feature. Users can follow these steps to set and reset passwords:

1. Setting a Password:
   • Enter the system menu (M6).
   • Find the password setting option (usually labeled as S6.5.1).
   • Enter the password value (typically ranging from 1 to 65535) through the buttons on the operating panel.
   • Confirm the password setting.
2. Resetting a Password:
   • Enter the system menu (M6).
   • Find the password setting option (S6.5.1).
   • Enter the current password (if already set).
   • Set the password value to 0 and confirm the execution. This will disable the password protection feature.

IV. How to Set Parameter Access Restrictions (Specific Parameters and Operations)

In addition to password protection, the Vacon NXS_NXP series inverters also provide a parameter access restriction feature, allowing users to restrict access and modification of specific parameters. Users can follow these steps to set parameter access restrictions:

1. Enter the System Menu (M6).
2. Find the Parameter Lock Option (usually labeled as S6.5.2).
3. Enable Parameter Lock: Set the parameter lock option to “Locked” and confirm the execution. This will restrict access and modification of most parameters.
4. Disable Parameter Lock: When needing to modify locked parameters, first set the parameter lock option to “Unlocked” and confirm the execution.

V. How to Achieve External Terminal Forward/Reverse Control and External Potentiometer Speed Regulation

The Vacon NXS_NXP series inverters support motor forward/reverse control through external terminals and speed regulation through external potentiometers. Users need to set the following parameters and connect corresponding terminals:

1. Forward/Reverse Control:
   • Parameter Settings: No specific parameter settings are required, but ensure the control signal source is set to external terminal control (P3.1=1).
   • Wiring: Connect the external forward button or switch to DIN1 (or the designated forward input terminal), and connect the external reverse button or switch to DIN2 (or the designated reverse input terminal).
2. External Potentiometer Speed Regulation:
   • Parameter Settings: Ensure AI1 (or the designated analog input terminal) is set to accept analog voltage or current signals (specific settings depend on the potentiometer type).
   • Wiring: Connect the output end of the potentiometer to AI1 (or the designated analog input terminal), and connect the common terminal of the potentiometer to AI1- (or the corresponding common terminal).

VI. Fault Codes and Their Solutions

The Vacon NXS_NXP series inverters feature comprehensive fault diagnosis capabilities. When a fault is detected, the inverter will display the corresponding fault code and fault information. The following are some common fault codes, their meanings, and solutions:

1. Fault Code F01: Overcurrent
   • Meaning: Motor current exceeds the rated value.
   • Solution: Check if the motor load is too heavy, and check for short circuits or grounding in the motor and cables.
2. Fault Code F02: Overvoltage
   • Meaning: DC bus voltage is too high.
   • Solution: Check if the power supply voltage is too high, extend the deceleration time, or increase the braking resistor.
3. Fault Code F03: Ground Fault
   • Meaning: Motor or cable grounding.
   • Solution: Check the insulation resistance of the motor and cables.
4. Fault Code F05: Charging Switch Fault
   • Meaning: Charging switch failure.
   • Solution: Check the charging switch and its connection lines, and replace the charging switch if necessary.

(Note: The above are only examples of some fault codes. For a complete list of fault codes and solutions, please refer to the inverter user manual.)

Through this guide, we hope to help users better understand and use the Vacon NXS_NXP series inverter user manual, achieving efficient and safe frequency control.

Table of Contents

1. Panel Start, Stop, and Frequency Speed Adjustment
   • Panel Start and Stop Operation
   • Panel Frequency Speed Adjustment Settings
   • Manual Adjustment of Voltage/Frequency Ratio Parameters
   • Inverter Initialization Procedure
   • Password and Parameter Access Restriction Settings
2. Terminal Forward/Reverse Control and External Potentiometer Speed Adjustment
   • Terminal Forward/Reverse Control Settings
   • External Potentiometer Frequency Speed Adjustment Settings
   • Explanation of Required Terminal Connections
3. Fault Codes and Troubleshooting
   • List of Common Fault Codes
   • Fault Meanings Analysis
   • Troubleshooting Methods

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1. Panel Start, Stop, and Frequency Speed Adjustment

Panel Start and Stop Operation

The Danfoss FC 101 series inverter can be started and stopped via the Local Control Panel (LCP). The specific operations are as follows:

• Start: Press the “[Hand On]” key on the LCP to start the motor.
• Stop: Press the “[Off/Reset]” key on the LCP to stop the motor. This key can also be used to reset alarms in alarm mode.

Panel Frequency Speed Adjustment Settings

To achieve panel-based frequency speed adjustment, the following parameters need to be set:

• 3-02 Minimum Reference Value: Sets the minimum allowable frequency reference value.
• 3-03 Maximum Reference Value: Sets the maximum allowable frequency reference value.
• 3-10 Preset Reference Value: Used to set one or more preset frequency reference values, selected via keys on the LCP.

Manual Adjustment of Voltage/Frequency Ratio Parameters

To manually adjust the voltage/frequency (V/F) ratio curve, the following parameters need to be set:

• 1-01 Motor Control Principle: Select [0] U/f control.
• 1-55 U/f Characteristic – U: Set corresponding voltage values for different frequency points.
• 1-56 U/f Characteristic – F: Define the frequency points in the V/F characteristic curve.

Inverter Initialization Procedure

Initializing the inverter restores its parameters to default settings. There are two initialization methods:

• Recommended Initialization:
  1. Select parameter 14-22 Operation Mode.
  2. Press the [OK] key, select [2] Initialize, and then press the [OK] key again.
  3. Disconnect the inverter power supply and wait for the display to turn off.
  4. Reconnect the main power supply.
• Two-Finger Initialization:
  1. Disconnect the inverter power supply.
  2. Simultaneously press and hold the [OK] and [Menu] keys.
  3. Hold the keys for 10 seconds while powering on the inverter.

Password and Parameter Access Restriction Settings

• 0-60 Main Menu Password: Defines the password for accessing the main menu.
• 0-61 Extended Menu No Password: Choose between full access, read-only, or no access.

2. Terminal Forward/Reverse Control and External Potentiometer Speed Adjustment

Terminal Forward/Reverse Control Settings

To achieve terminal-based forward/reverse control, the following parameters need to be set:

• 4-10 Motor Speed Direction: Select [2] Bidirectional to allow both clockwise and counterclockwise rotation.
• 5-10 Terminal 18 Digital Input: Set to [10] Reverse to control motor reversal.

External Potentiometer Frequency Speed Adjustment Settings

To achieve external potentiometer-based frequency speed adjustment, the following parameters need to be set, and terminal 53 (analog input) needs to be connected:

• 3-15 Reference Source 1: Select [1] Analog Input 53.
• 6-00 Disconnect Timeout Time: Set the timeout time for analog input disconnection.
• 6-01 Disconnect Timeout Function: Select the function when disconnected, such as lock output or stop.

Explanation of Required Terminal Connections

• Terminal 18: Connect the digital input signal for reverse control.
• Terminal 53: Connect the external potentiometer for frequency speed adjustment.
• Terminal 27: Typically used for start/stop control, specific function needs to be set in parameters.

3. Fault Codes and Troubleshooting

List of Common Fault Codes

• Alarm 2: Disconnect Fault
• Alarm 3: No Motor Connected
• Alarm 4: Main Supply Phase Loss
• Alarm 13: Overcurrent
• Alarm 14: Earth Fault
• Alarm 24: Fan Fault
• Alarm 30: Motor Phase U Loss
• Alarm 95: Broken Belt

Fault Meanings Analysis

• Disconnect Fault: Analog input signal is below the set value.
• No Motor Connected: No motor is connected to the inverter output terminals.
• Main Supply Phase Loss: Main power supply has missing phases or unstable voltage.
• Overcurrent: Motor current exceeds the inverter peak current limit.
• Earth Fault: Output phase is discharged to earth through motor cables or the motor itself.
• Fan Fault: Fan is not running or not installed.
• Motor Phase Loss: One phase is missing between the motor and the inverter.
• Broken Belt: Torque is below the set value, indicating a possible broken belt.

Troubleshooting Methods

• Disconnect Fault: Check analog input terminal connections and signal source.
• No Motor Connected: Check motor connections to the inverter.
• Main Supply Phase Loss: Check main power supply and voltage stability.
• Overcurrent: Check motor load and parameter settings to ensure motor compatibility.
• Earth Fault: Check motor cable and grounding connections.
• Fan Fault: Check fan resistance and operation.
• Motor Phase Loss: Check motor connections and cables.
• Broken Belt: Check the drive system and belt condition.

By following the above settings and troubleshooting methods, users can effectively operate and maintain the Danfoss FC 101 series inverter, ensuring its stable operation and meeting application requirements.