Need help...I have a Kone KCM831 with a V3F25 drive. The machine is an MX10. Two days ago there was an entrapment, elevator stopped between 1st and 2nd landing. I found three main fuses blown. Replaced fuses, powered up and found no faults. Elevator ran fine. Quickly checked motor and drive, everything seemed ok. Just got the same call with elevator stopped at same place in hoistway and found main breaker tripped. This time I megged the motor and it checked out. Now have car set to run top to bottom nonstop. I haven't seen drive or motor problems so severe and intermittent. Thanks in advance for any help!

I would look at the Main and E-Brakes first. The Washer in the center on the Shoe should be loose enough to move with your fingers. You may be dragging a corner of the Linings and as you run it slowly heats up the Drum and you start dragging the whole Brake Lining. You certainly should register some sort of Drive Fault. The throw on these Brakes are in the .002 to .005 range.

john jay Thanks for the info, hadn't thought about the brakes. After watching it run for a while now, it is throwing some drive faults (0026). Gonna check the brakes now.

Also make sure fans under drive are ok

Brakes look good and fans are running. Since making test runs, elevator has not blown mains but has intermittently shut down. Shut down faults are 0026, 0036, 0109. Seems like drive?

026 is a drive not ok. The drive sends a fault to the CPU and shuts down, 036 is more of the same, it says the Drive released the main contactor during a run. 0109 is position lost, it says the Drive count differs more than 300mm at 30. 30 is the door magnet and sensor. So everything indicates that the car is getting lost at a spot in the Hoistway. You need to go over your magnets for sensors like 77u,77n,61un and check that the Encoder on the Governor is driven properly. these are just some places to look, it may be a Drive issue also. Good Luck.

Great info, thanks. Still trying to figure out how this ties into blowing the mains earlier in the week.

Sounds more like an external problem which has since been repaired by others e.g. incoming mains cables possibly, or underground cables shorted or water damaged etc.
Can't see a fault such as you have described just disappearing.

I've heard that dry rails can play havoc on the drives. Just my two cents.

Certainly can. When the drive lifts the brake any additional load increases current draw so I have had quite a few main breaker trips or current o/loads on drives. Incidentally that can be for any type of control too. Also don't assume the rails are dry it could be that they have shifted on their bolts. I have never understood why companies didn't include roller guides with these MRL types and the difference isn't that big.

I've been seeing a lot of ropes slipping lately and then the drives try to catch up and kick out a fault. Eco and Monospace have virtual hoist ways so one way to see if you losing traction is to run hoist way access down from the top floor till it stops. Make a mark on the rail where it stopped next to one of the magnets. From the keyswitch run the elevator up and down 3 to 4 feet each time for maybe 10 times. Run the car all the way down on hoist way access till it stops again . It should stop at the mark you made on the rail. If not your slipping , may need to tighten the brakes or take a counterweight out.

OMG Traction is absolutely horrible on any of the KONE MX Machines. Nothing but problems.

Thanks for all the info guys. We actually found out it was a problem in the drive. Sent it off to be repaired. When we reinstalled the drive we cannot access our drive parameters. The 6 menu just comes up with a 0 and you can't scroll. Anyone else see this before?