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Topic starter
05/10/2016 8:32 am
Car will not move. Brake picks, we get motor field voltage, but not armature voltage. We are getting the input to the 5ea 6 pulse firing board. We have the 115 input voltage to this board and to the pulse distribution board. Ohmed all connections between boards. Am not sure how to check the output voltage of the pulse distribution board. We have swapped all boards out with a running car from another location and still not getting anywhere. The only thing we have not swapped out is the main SCR's before the armature. One note of interest( do not know if it helps) is when we were checking voltages on the pulse firing board we mistakenly used terminal 10 as our common and when we hooked the positive lead of our meter to terminal 4 of the pulse firing board the car tries to move but can not as if it does not have enough power. We did not pursue that method any further. How do we verify the output voltage signals to the pulse distribution board?
Topic starter
05/10/2016 9:03 am
I should add, that when we are checking our voltages and it tried to run is while we have a run command in.
05/10/2016 9:53 am
Sounds like you are not getting a pattern. I'll have to look at a print.
05/10/2016 10:30 am
So you have a pattern to the field 4 EA from 201 to 121? If you do but do not from 230 to 121 on the 5EA and you have swapped every board then I would be looking at P2 and the RR relay contacts. If you don't have anything to the 4EA then then would start from the 9EA 168 to 169 and follow the pattern through the print. I have seen the 18RT diode on the 2CA at B-12 short and zero the pattern but you have swapped that board. Hope this helps.
Topic starter
05/10/2016 6:38 pm
We are going to back up and regroup. Start over from the beginning. Hope to be able to get back this week. It is not a priority yet, but have spent a lot of time in between jobs there.
05/10/2016 10:05 pm
So if it were me, the first thing I would check is Motor Field Current. Pull one of the Motor Armature Leads off of the Contactor, pull one lead off of the Brake Coil, set the car on inspection and arrange it so you are trying to run down. Place a Meter in series with the Motor Field at point 129. The meter should be on the 10 Amp DC Scale. Place another meter on DC Voltage around the Field feedback Resister, 1 Ohm 160 Watts-63R. with the car trying to run down you should have 2 volts and the meter in series should have rated field current, if not rotate the max field pot until you have rated current and adjust 63R to have 2 vdc. The Car won't move with the Armature and Brake disconnected. By the way you should be tripping the Comparater, if you aren't that indicates no Motor Field. If you are,jump the comparater contacts 5 and 6 on the comparator board. The next thing to check after that is Armature Current and feedback, but thats another procedure.
Topic starter
06/10/2016 1:48 am
Thanks John, we have been following the adjusters manual. That is how we know we are getting the field voltage. We are good up to the armature current. We are trying to get the one volt across 64R. We are not getting anything here. We have the feedback transformer and not a rectifier, first thought that was bad, sent out to Access Electronics to be checked. Same thing.
I hope we can get back there this week or the first part of next week.
06/10/2016 2:24 am
I wish you had said that earlier, I wouldn't have written such a long explanation that you didn't need. A good place to look at this point would be the 1RT Rectifier and 1CT Transformer, and the 1EA OP Amp Bd. If you haven't already.
06/10/2016 3:13 am
Some other random thoughts. Check the contacts on the M Contactor and Motor Brushes on the Armature. The way you check the 6 pulse firing board is with an Oscilloscope, Terminal #1 to 2,3,4,16,17,18. The pulses should be 16.6 ms apart. Also use the Scope to check the output of the pulse distribution bd. and the pulses across the Armature. There should be 6 pulses.