VFD - abnormal readings!!!!!

[ekuegler]

Wondering if anyone can help here.

We have an ABB ACV700 VFD, supplied by a 690vdc bus, 690vac to a step up transformer to 2600vac supplying a downhole ESP motor. Drive currently operating/running - however pump discharging very little....? Hertz = 3.5-4Hz, ref = -25.7 and current 413A. This is very unusual, drive has not tripped and no alarms indicating, what could be the cause of such unusual readings?????

 

[MiketheEngineer]

It's broken??

 

[KllrWolf]

How big is the motor you are running? What is the normal running current? How long has the system run normally before this happened?

It does sound like the VFD is really off at only 4Hz. That would mean the motor is only running at 120 RPM. If that is correct, it means very low flow. It would also mean at that speed you will very quickly destroy the bearings in the motor.

If the current is correct and the VFD is in error for the frequency, you may be running the motor/pump backwards. This really only applies if the system is just being commissioned or electrical work was done and the wiring got swapped. Switch 2 phases from the motor side of the transformer and recheck.

 

[jraef]

There are any number of possible issues and you have not provided anywhere near enough information.

Was this system engineered to work together or did someone assume it was going to work fine? If it was engineered, have you spoken with the engineer?

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