Home Forums General Discussion Technical Questions Miprom 21 Only Goes Down

As stated above, it only runs down. Even on construction, it only goes down. The brake is picking. They have put a new motor encoder and governor encoder on it. A different relay pilot board. New relays on the interface board. I think they said they have even changed the MSU board. The ETS board has not been change, they're looking to get one. Car only runs 200fpm so it has no NTS switches or board. They have followed the straight line to their best, when trying to run up all of the up relays pick. It has the old AB drive so I'm wondering if it has went PHFFT. Any suggestions?

When you say it has an old AB Drive, is it the one with a 16-position Rotary switch on the drive board? If so, position 9 monitors the speed feedback from the tach. 0 to -8 in the down, and 0 to +8 in the up. Also, just a thought, are you getting the same polarity at A1 and A2 on the M switch? And lastly, do the DS fault indicaters on the main control board indicate a fault? the 4 LED'S add binarily.

Are you logging any faults? Do you have the black Miprom 21 book?

The AB drive is obsolete, if you reach out to Kone they offer a conversion kit to upgrade to a magnetek drive very involved process. Wiring changes,new CPU,etc.

Got over there today. Still the same thing. An AB 1395 drive. Found some drive boards, no ibe has an idea if they're good, bad or indifferent. Tried them and the drive would not even come up. Fails to initialize or reinitialize with any combination. Put the old stuff back in it. Same story, up is down and down is down on construction. Plugged in the other cards and same thing. The cpu sees the up and down. The failures are a comparator errors. I've had to change out the drives on other units so it's not a big deal. Another day.

I think I’ve seen this when MSU adjustment Jog was set wrong

When the elevator doesn't know where it is, it will always search down. So it may be something like an up stop or up terminal slowdown in the wrong state.

I have gone back to construction mode. No CPU or PIO card. Plugged the the smart cards to see it recognizes up as being up and down as being down. It will log a comparator error and it sees the up and down signals correctly. I had the car in the middle of the hoist way on inspection. The directionals and slowdown are seen by the CPU as being in the proper state. When the wires are disconnected on TB3, it sees them. Going try a different set of ribbon cables but I'm still leaning towards a drive problem.

Finally found a motion adapter board that will boot and works. Probably the last one around here. Tried two others that no one knew if they were good, bad or intermittent. It's running for now.