Kreutz, I just looked at the schematic, didn't see the note on the normally closed. (In fact I've never seen normally closed switches drawn normally open) I've never had any issues running with closed switches, but have normally open. One spindle motor I have is just a pure noise generator! It's easy to see the effect on open switches by just turning on the machine and disconnecting the switches. Virtually all the noise is switching emi from the choppers, sometimes spindle motor commutator noise. Physical layout of wiring can cause issues, avoid parallel wires.
KISS principle, don't make it more complex than it needs to be.
Phil, Still too many interests, too many projects, and not enough time!!!!!!!!
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