Home Forums General Discussion Technical Questions mid 70s montgomery tractions

hey guys. I just had 12 mid 70s Montgomery tractions added to my route. all have mg control with relay logic controllers and a damper motor for shunting. ive got a couple that are going into the top over travel. ive replaced a few of the relays and changed a few brushes. it lands at floors dead on and the brake seems to be dropping fine. any suggestions of what else I could be looking at would greatly help. thanks

So does it pull through the brake into the OT limits?

when the Genny is idle and with no demand, what voltage are you measuring across two adjacent Brushes. It should be like a volt or so. you may be building up enough voltage to pull through the Brake. also check that your Suicide Circuit Contacts are good and the circuit actually works as intended. Are you Rolling Back when you leave the top floor. This is also something to look at. Are you coming in to the floor to hot, is the Damping circuit working. Have you seen it actually go into the Overhead, or does it do it intermittently?

I dug a bit deeper and this car has been doing this for about a year and it is intermittent. I have yet to see it happen and the passengers are usually gone by the time I get back down from the mr so I cant ask them what floor they got on. I will check genny voltage my next visit. im thinking it may be rolling when the brake picks to go down. the brake sounds a bit sloppy but ive only had these units under my care for less than a week so it may take some time to get it under control. thanks

Got er figured (I think). Found that the car was. Clipping an interlock on the 2nd from top landing and losing its position. And then it would go through the top floor onto the limit. Been running for a bit more than a week now with no issues

Good find, but the terminal slowdown switches should be looked at. They should have slowed you down in that situation. They may need to be tweaked.

A post script to my previous post. If you dropped everything when you clipped the lock and slid into the overhead from there, and the Brake is in proper adjustment, you have found the problem.