MG drive problem - 1944 10EE

Hi all.
I just acquired a Monarch 10EE (July 1944 MG unit). The back story- I got it from the grandson of the previous owner, He said that everything worked but it had been sitting for several years as his grandfather health declined.
When I got it the AC motor started right up, but the DC motor does not respond. So I started looking for loose connections and found a wire attached to a relay in the DC panel (I think it is the FL relay) which makes sense with the symptoms.
Can anyone tell me where the wire should be connected?

Assuming this does not fix the problem, it looks like I need to dig into the diagnostics. I found several threads on this site, can anyone recommend the best thread to start with?
Thanks,
Rich

rich hutch said:

Hi all.
I just acquired a Monarch 10EE (July 1944 MG unit). ...
When I got it the AC motor started right up, but the DC motor does not respond. So I started looking for loose connections and found a wire attached to a relay in the DC panel (I think it is the FL relay) which makes sense with the symptoms.
Can anyone tell me where the wire should be connected?

...
Thanks,
Rich

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Welcome to the forum, Rich. I moved your post to a new thread, to keep from muddying up Mike's thread.

Motor/generator (MG) machines don't have a FL (flield loss) relay. That's the anti-plugging (AP) relay. The broken lead should connect to the moving arm of the relay, as shown in the photos below:




The wire goes into a hole in the top of the arm and is probably soldered to the the arm. If you look, you should find the broken end of the wire sticking out of the arm. Be careful what kind of wire you use to replace it, if that's necessary; a wire with a large number of very fine strands is usually used to give it maximum flexibility.

If you use an alligator clip to jumper between the wire and the arm, the machine should operate (assuming that your exciter is putting out voltage). The three resistors in the upper right corner of the panel are a common failure point for this panel and should be replaced.

Cal

thank you!

Hi Cal, You mentioned that the three resistors should be replaced.
Do you have source for replacements (Monarch)?
So far they seem to be working, but want too be prepared.
Rich

This post has part numbers for the resistors:


Prices of some of the resistors have gone up, as you would expect. The power rating of the resistors is due to the fact that they're the same physical size as the originals. They are massively over-rated for the job (which is a good thing).

Cal

When I got my second 10ee a round dial MG it hadn’t been run in 20+ years and looking rather rough. Before digging into cleaning it up I’d see if it powered up first. The thread I used was 10EE - No Exciter Voltage to check things out. After doing what I could without applying power I finally got to that point and fired it up. I got the ac motor spinning in the right direction but no spindle. Going through the check list I had no dc voltage. Fallowing the flashing procedure several times it came back to life. I still had to clean all the relay contactor pads as they had carbon build up. I still need to get an appropriate power source as my current RPC isn’t large enough to handle the load.
Good luck Z