[GreenKeys] M28 - mystery LESU

[Duncan Brown]

I'm checking out a M28KSR that looks like it has had some major rewiring 
done to it.

All the jumpers that are normally on terminals 4-14 of the cabinet 
terminal blocks have been removed.  There were two, 4 conductor, 
external cables connected to the cabinet terminal block, all 
unterminated, except for a 2k power resistor (loop current limiter) 
connected across  C10-C11.

I see no designator on the LESU and the color codes of the cable from 
the LESU to to c5 - c14 do not match the colors I see on 2874WD (or any 
others).  The LESU has what looks like a Line Shunt Relay, a 120VDC 
power supply (with monitor jack), a Motor-Stop relay and an 120VAC input 
panel ( lamp switch & fuses). See picture enclosed.

Can anyone identify this LESU?

I tried to remove the LESU by removing the big screws.  The LESU was 
loose, but would not come out, apparently because of the front panel 
power switch extension mechanism.  I expected it to disengage when I 
lifted up the LESU, but it did not.  Is there something in the switch 
extension mechanism that has to be removed/released?


Thanks,

Duncan
K2OEQ



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