Home Forums General Discussion Technical Questions Miconic A trouble

have a new job, miconic a with extended vfac drive. very intermittently, the car will shut down with a ems KSD fault. so far it looks like only at the top landing. what i have found is that the DS5 led on the VEC board will come on, and that drops DS1 led on VEC board which drops brake and controller logs ems KSD fault, it pauses for a few seconds, then levels into floor and ready to go again. I found some info regarding DS5 led on the vec board, and it indicates if it comes on, the 5,15, and 24 volt power supplies from ps1 maybe to low, or to low. I checked 15 and 24, and there right on, i readjusted the 5 volts per directions, adjusted it til M1 contractor dropped out, which is hi limit, then came back down enough to keep 5 volts at MTV board. same outcome. there are some notes regarding maybe the DC bus is not bleeding off correctly, but the car runs fine everywhere else except a hi speed run into the top floor, have only seen it on a hi speed run to top floor. one floor runs to top floor don't seem to cause this. although it may just be a coincidence . any one have any ideas not sure where to go. replace VF2 board, replace VEC board, or something else

When its approaching the top landing, does it step down in speed properly? Does it go into FLVL, then step down to LVL? When in LVL is your velocity 4fpm? What happens with KLU & KLD? When the issue happens, could you place it on inspection and check how close its to the floor and directional limit switch.

you may want to check your NTS ETS sequence. one of them may be causing a problem.

After further runnin. The car will fault out at other then the top floor but still only
In up direction. Car slows down and right when it is on the door zone switches it drops everything out. Never seen in down yet

Do you have AC voltage on your power supply? Still could be a problem with power supply.

It's going to be your power supply. I really can't remember which way it goes...Either the Vec board likes the 5VDC high but not too high or the MTV likes it high! Problem is they use the same power supply. There was a Technical Support fix rewiring the outputs to help with voltage fluctuations . We just added another supply...One for the MTV and one for the VEC board. Problem never returned?

no ac ripple on power supply, stragnge thing is i have only see it happen in the up direction. ran it down as many times as up, an only faults in the up direction.
guess sometimes thing just don't make sense, time to start changing parts. Looks like power supply first, will keep you posted. thanks half pick, did see the wiring change on some paper work i have, looks like the change had already been incorporated. but ds5 coming on does say power supply problem so guess i will have to keep it simple and change it out

I have seen this occur V2V pulses M1 precharge relay empty car deceleration into the top floor. Older VL cards needed new caps

so far no luck, still intermittent , but it happens in both directions , during accel, decel hi speed etc. sometimes runs for 2hours sometimes 15 min. so far we have replaced the power supply, v2v board, vec board, mtv board, all plug in relays, ran car on test with safety circuit jumped out, door locks jumped, gate jumped. checked braking transistor and associated wiring, all to no avail. this one is being a pain. running out of parts ha ha, gonna have to start swapping drive parts from car to car. will let you know.

Any chance of a traction loss problem? Slow accel/deceleration rates and see if it stays running.

smitty, i found some info on the ds5 led coming on, besides power supply it mentions the upper and lower capacitor banks on the VL cards may cause this if they are unbalanced, it says unbalanced by around 50 v. i did find that voltage across the upper bank of caps was around 345v and it held steady with maybe a 5 volt drop. however the lower bank measured around 304v, and it dropped to 294v when car was running, both upper and lower banks increased as the breaking igbt turned on, but they are near 50 v apart, other cars are around 20 volt difference. from what i see of the circuit, it may just be some weak caps like you mention. gonna pull all 3 boards and have them checked out. keep you posted