Notifications
Clear all
Topic starter
13/10/2010 11:10 am
I have a 401 car that runs fine on normal operation, but when you try to run car on inspect, the car will only run in the up direction even when you give it a down command. the voltage across the generator field is always the same polarity, 15vdc, which gives 35vdc output from the generator armature of the same polarity, causing car to run up. if i reverse the gen field wires then the car will only run down regardless of the up or down signal. other then this problem the car runs fine during automatic operation. any thoughts.
16/10/2010 7:04 am
does this happen only with the OMT or on TOCI or access sw's?
Topic starter
16/10/2010 11:34 am
hey greenpants, nice screen name, i take it you are an otis man. anyway while troubleshooting the problem i was referring to, the car was in the overhead and would only run up, so i reversed generator field wiring and ran the car down on inspect to the half way point, then i put the gen field wiring back to original and let the car go on automatic, it struggled a few times with the initiation run and eventually initiated and returned to service with no problems. any way it was late and i decided to return the next day to tackle the inspection run problem. i ran the car with the omt in the velocity test mode and it ran fine at any speed commanded. then i ran the car in the mode which compares ppt to encoder signal which is open loop i believe and it ran fine, so i tried inspection and all was fine, very strange, as the day before it would not work. after a day of troubleshooting i was able to find the trouble, the cop with cop2 board had been knocked off its mounting brackets and had slipped about 8 inches down which put stress on the connector to the cop2 board, which bent a couple of pins on the ribbon cable to the board, if i wiggled this connector i could duplicate the problem, the cop would start beeping when the problem existed, i straightened the pins and reconnected the ribbon cable and no further problems. I am not sure but it was either the load weighing signal was not being transmitted to the controller, or it was the loss of communication between the cop and the controller. some otis guys say it can not be the load weighing signal but i suspect that that was the problem but can not be sure, do you have any thoughts on this?
Last edited by Scott Davidson; 10/16/10 03:36 AM.
17/10/2010 12:26 am
thats a good one. i wouldnt think the load weighing signal would do that it would roll back a few inches at most before it ran down or it would fault out. could be that it shorted another circuit dealing with inspection. i have had weird issues with mounting screws coming loose on the cop boards and getting loose grounds but nothing like your problem.