Home Forums General Discussion Technical Questions MCE IMC Drive issue

I have a job with a recently repaired F4 drive (IGBT). Car runs, however the current sits at just over double the rated motor current. Verified the data tag details and that they successfully saved on the drive.

Any ideas what else could be checked? MCE only recommends upgrading to an F5 but I think there is still hope.

where is the motor field voltage/current at? Has the motor been checked out?

Is the current high at contract speed or during decel/a elevator?
Is it being run in closed loop? LF30?

Check the brake(s). Be absolutely sure you don't have a brake dragging. I just had a torin gearless machine with normal and emergency disk brakes that was ran with a F5 drive. Car was shutting down with faults for commanded car speed not matching actual speed. The emergency brake was dragging just enough to cause it to vary enough to shut down.

I would think a dragging brake would easily double the current your drawing.

Unfortunately the car developed a new issue that wouldn't allow me to run it some more (bad U15 EEPROM on DDP).

Current was sitting at 64A on the drive (I couldn't verify what it was with a meter before it crapped out). Didn't get a chance to get voltage. Motor had no obvious issues with shorting/grounding. Contactors are good as well.

Current was at contract speed while being run on closed loop.

Brakes are good, they actually have too much lift if anything. Its an older machine but when opening brake manually she moves up without issues

Silly question but have you verified its not single phasing?
Also try running on open loop and see if there is a change, a bad encoder can also cause this. What is the bus voltage?

Ya that U15 is a bitch. I keep some on the van. In my experience if you change a parameter on an IMC controller there’s about a 50-50 chance you’ll get a checksum error and have to replace that chip.
And for the original issue, is that what the drive says? If it is, does a clamp meter agree?

Mce and there chipsets seem to be a money maker for them. I may be wrong but the U9 chip they have to program
We had a bunch at one time go bad so I started burning copies of the one that appeared to still be good.

Correct wasn’t single phasing when it ran the few times. This was my next step once I get it going again. If I recall my glance was around 700 at idle (mind you I’ve seen a few drives past few days so I may be wrong)



Hopefully I’ll find out tomorrow, I have some new chips to get it running to continue trouble shooting