Home Forums General Discussion Technical Questions Dover leveling issue

Have an older Dover traction with leveling issues. On an up run, all seems well; speeds reduce and levels into landing with no perceivable issues. However, going down, will overshoot the floor, stop, then, with up contacts pulled in, ease down a bit more, then stop and level in in the up direction. If I give it a bottom call, as it goes into this series of events, it will drop enough to hit the finals, and thereby drop the P contractor. When I jump the finals, U picks, brake picks and car moves down.. To get out of first landing I had to force up, brake and P by hand, allow to slip traction for a moment, then it moves up. This problem began a week or so ago, and while troubleshooting, the MG set let all the magic smoke out, and since I have yet figured out how to catch it and put it back, had to pull gen set and send for rewind. I had my fingers crossed that problem was in generator all along, and that when I got it back problem would have been rectified. Generator was reinstalled today, and obviously, since I am posting here, still having same issue. If anything, I think it actually may have gotten worse, or so it appears anyway. what I have seen goes something like this: car overshoots floor, LD (1&2) drop, and immediately LU (1&2) pick. Since ther is no time between these two events, and the fact that the "10" relay (brake) is in series with U and/or D, it never drops. Car drifts down at about 1.5 fpm, about 4", stops momentarily, drifts another 2 " or so, then levels up. I have been reading these forums all night and tend to believe it is in compounding, but is this something that can or will change over time? As I indicated problem was same thing before generator was sent out. Another possibility, from what I have read is series windings being reverse polarity, but again, issue was there before reinstalled. If either of these appear to be culprit, 1; how do I verify polarity? 2; can somebody post readers digest version of how to check/ set compounding? Just a young gun in the industry, and have not yet had to do this. Thanks tons from Cincinnati!!!!

Check out this previous post by Scott Davidson. This should get you on the right track:

Dover Compounding

Yup sounds like a compounding issue. Your car seems to be over-compounded You can run your car up and down on inspect in leveling speed while you have a tach on the drive sheave. Compare the up to down speed. If its pushing down faster compared to the drive up its over-compounded. You'll have to take out some of the series field. The series field is helping the magnetism of the generator output too much. The schematic for the generator field connection should be on the inside cover of the motor connection/generator connection box. I had a mg that needed to be recompounded everytime the weather would change, what a pain and thats in San Diego. Can't imagine what it would be in a more drastic climate region.

I had read that post earlier ( very nicely written ). I looked in junction box yesterday trying to find said directions, and are none. Three elevators in the building and none of them have this information. All have been re-done at some point in their lives, so they have been apart and painted. They are original Dover generators. I traced wiring from power panel back to generator, and have identified where they are all landed, but don't know whee to go from here.... For what it might be worth, winding taps look sort of like this:

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Thanks for any help you can throw my way!!!!!

I see that the forum knows better how to format my post than I do. The three taps on winding that are closest to commutator are grouped together toward left side. Second row first Is somewhat centered under the first and second From top row and then has a second tap off to right side of winding. Third row has one tap positioned below first tap from second row.

as a cheat you can compare your other genny settings with the other 2 lifts in the bank. for instance find the series field on the print, measure your resistance(disconect wires first) then compare that to another lift. now dont take that as gospel because it depends on a number of factors wear and tear etc. at least that will give you a base to compare lift settings.

Before you change the taps in the generator, check your 14 and 15 switches for proper operation and contacts. The armature is known to back out and not let the relay work (drop and pick) properly. Also, be aware that there are both high speed compounding and low speed compounding taps in each field of their generators. Only play with the low speed taps if you don't want further problems.

Found what I needed. Didn't want to just start moving leads around without knowing what was what. Was givin direction by buddy with 20+years at Dover. Ended up taking out like 5 winds...