HP-IL device Seal s5801c

[Dave Frederickson]

(02-06-2021 06:55 PM)John Keith Wrote:  In any case I think that it would be safe to connect the transformer briefly to 120VAC and see if the logic circuitry is getting 5V.

I think this is a bad idea. Typically, industrial chassis that accept modules, like this one, provide DC power from a separate module plugged into the chassis backplane.
The transformer connections are probably the output to the AC motor.

Dave