Cause : NTC thermistor wire break comes when a wire break is found in the NTC thermistor detection circuit. The cause of this error is the NTC thermistor itself might be damaged or defective or problems with the wiring connected to the NTC, such as open circuits or short circuits.
"nrb" fault in Fuji FRENIC-VG drive indicate "NTC thermistor". This means a problem with the NTC (Negative Temperature Coefficient) thermistor used for temperature sensing within the drive. The thermistor is critical for monitoring the temperature of various components, such as the heatsink or power modules, and helps protect the drive from overheating.
Troubleshooting Steps:
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Inspect the Thermistor and Connections:
- Check the physical condition of the NTC thermistor for any signs of damage or wear.
- Inspect the wiring and connections between the thermistor and the drive’s control board. Ensure all connections are secure and free from corrosion.
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Check for Overheating:
- Verify that the drive’s cooling system (e.g., fans, heat sinks) is functioning properly.
- Ensure that the drive is installed in a well-ventilated area with adequate cooling and that the ambient temperature is within the drive’s operating range.
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Monitor Ambient Conditions:
- Check the environment around the drive for excessive heat sources or poor ventilation that could lead to higher operating temperatures.
- If necessary, improve the cooling or ventilation around the drive to maintain optimal temperature conditions.
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Test the Thermistor:
- If you have the equipment and expertise, test the NTC thermistor with a multimeter to check its resistance at various temperatures. Compare the readings to the specifications provided in the drive’s manual.
- If the thermistor is found to be faulty, it may need to be replaced.
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Inspect Drive’s Control Circuitry:
- If the thermistor and its connections are in good condition, the issue may lie with the drive’s control circuitry. This may require more in-depth diagnostics or the assistance of a qualified technician.
