I know it is kind of confusing getting it all straight in the mind as it was for me. But I think once the vacuum switch switches, the flow is out the NC creating the voltage drop. When it is not switching it flows out the NO giving a normal voltage reading.

How many people have tried this so far with success? I believe Joe has but I am not sure?? Anyone else?

Having the switch set to the proper vacuum setting is the key!

__________________
-disav

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