I have a Dover T4 that is only faulting out in the down direction on a multi-floor run. All up runs are successful, multi floor and one floor runs are perfect. Down one floor runs are perfect BUT on a down multi-floor run it appears the current or speed monitor for the drive is not happy and the elevator faults out.

The faults are 54, 642 and 56

I have addressed WDPF, DE, AND ES MODULES. I HAVE LOOKED AT THE C1 CONTACTOR AND I AM STRUGGLING WITH CONSIDERING THE VELOCITY ENCODER BECAUSE OF THE UP FLOOR OPERATION BEING GOOD.

Thanks, for reading

Very possible a bad IGBT. Need to take some readings on them. Bad connection on a ribbon cable?

Hi West,
Definitely is something wrong with the enconder.
When you send the car down to next floor the drive receive a certain number of pulses from down encoder, so you need to check floor by floor and 2 floors by 2 floors, and see on controller how many pulses do (If do the same pulses like up encoder).
By error codes the 54 it says: "UP & DOWN encoder motion detected 1.5 seconds after the valve de-energized".
Hope can help you.

Hi West,
I would strongly agree with Nelson on this. I have seen these encoders fault directionally and only at certain speeds. The best way to check it is with a scope due to the high rate of pulses at or near contract speed. Otherwise, see if you can borrow a spare from somewhere and try it.

All the best!

Thanks Guys really appreciate your help
Ill keep you posted.