Home Forums General Discussion Technical Questions Dover DMC-I (no slow speed)

I’ve recently had trouble with a 3-stop DMC-I. If the car is at the bottom landing, and I give it an up call, the car will run up to the called floor with my high speed valve coil energized, but when my high speed valve coil drops out, my low speed valve coil does not pick up. The pump will continue running until controller times out. My valve coil is good, and I’ve traced the issue to an output from the main board (I wish I wrote down the terminal name) which is keeping my high speed relay picked, which is a problem since I know the relay needs to drop out for me to energize my low speed valve coil. If I remove this output wire when the high speed valve coil drops, the low speed valve coil will be energized and the car will level into the floor. Has anyone experienced this issue?

I’ve certainly seen this doing an NTS test. I want to say it’s because of a slowdown switch adjustment or the TSL contacts not breaking at the same time or something but I don’t remember. As for it happening on automatic, Selector Adjustment 2 is too low. Maybe left there after an annual. If the controller initiates the slowdown this won’t happen. Probably a 2 stop or you’d notice the overshoot at an intermediate landing.

So I was able to get back to this job, and it turns out it was overshooting the 2nd floor, and when it would hit TSL switches, this is the point where the pump would continue to run with no coils energized. Turns out I’m not slowing down when passing the 2nd floor at all. I checked my limit tree and tried making adjustments to my selector slowdowns. I attempted several hoist way learns with no effect on the issue. When I checked my CLC variables, all of my 27 (CLC outputs to SEL) variables would make sense. When I looked at my corresponding selector variables 3 (input flags from CLC), my inputs would be flashing on and off. I’ve got a selector from another job that I’m going to bring with me and start changing boards.

What’s the up speed of the car and what is Selector Adj. 2 set to?

I don’t know the up speed off hand but Adjustment 2 was set to 90 (adjustment 1 was set to 90 as well)

Update: Replaced the auxiliary sensor board on the selector and car is back up and running.