Hello everyone. I have a 525 VFD that is functioning properly as it displays the output voltage and frequency on the screen. However, I am not getting any voltage readings in UVW when using an oscilloscope or multimeter. I have tried V/Hz control, HIM control, and adjusting the parameters, but the issue persists. These tests are being conducted without the motor being connected. The input voltage is 480 vac and the PF is 525 15 HP. I am seeking advice from anyone who has experienced a similar issue and their recommended solutions. Thank you.
Hello, I am experiencing the same problem. Have you discovered a resolution?
Hello, I have identified an issue with the optos. The VFD had 6 incorrect optos.
Please inform me
Thank you for responding. I apologize for my lack of expertise. Could you kindly explain what an opto is for me?
Certainly, optocoupler, commonly used in electronic circuits for isolation and noise reduction, plays a vital role in ensuring signal integrity and protection.
Hi there, it's quite intriguing that your 525 VFD is showing the output voltage and frequency correctly, but you're not getting UVW readings. Sometimes, it's possible that built-in diagnostics in the drive are causing a discrepancy between what the drive's display shows and what your measuring instruments are picking up. Since you've checked everything under V/Hz control, it might be worth examining the drive's internal voltage feedback circuitry. I would suggest reaching out to the manufacturer's tech-support or consider having the VFD serviced professionally, especially if it's still under warranty.
Hi there! It's interesting that you're getting correct readings on the screen but not on your tests. I have come across a similar situation before; it may be a problem with your measuring devices. However, you could also check the UVW terminals, specifically the screw connections, for any loose, broken, or corroded terminals, as they could lead to a such voltage drop. Be cautious when performing these checks and ensure you disconnect the VFD from the power source. Please consult an expert if needed, to ensure safety.
It sounds like you've taken many of the necessary troubleshooting steps! A possible reason why no voltage is appearing at UVW could be due to the absence of a load (the motor) in this case. VFDs typically require a connected load to correctly regulate and display output voltages. You might want to try hooking up a dummy load or, if safe and feasible, the actual motor and retesting. Remember to ensure you're following all necessary safety maneuvers when dealing with such power.
It seems like you've already tried quite a few troubleshooting steps, so good job there! One thing to note is that not having a motor connected might be your issue here. VFDs are designed to work with motor loads, and testing without one can sometimes yield inaccurate results. If you have a spare motor around, try connecting it to the VFD and then check your voltage readings. If you still find an issue, then the problem might lie in the UVW outputs, and you may need to get your VFD checked or repaired.
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Answer: 1. Q: Why is my PowerFlex 525 VFD displaying output voltage but not providing readings in UVW? This issue could be related to incorrect parameter settings, faulty wiring, or internal VFD component problems. Further troubleshooting may be required to pinpoint the exact cause.
Answer: Potential causes could include misconfiguration of V/Hz control settings, HIM control issues, or calibration problems. It is recommended to check these settings and conduct thorough testing to identify the root cause.
Answer: Start by verifying the parameter settings, checking the wiring connections, and ensuring that the VFD is configured correctly for the intended application. If the problem persists, consulting the VFD's manual or contacting technical support may be necessary.
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