Hello,
I'm working on a small router driven by a Centroid Acorn. I need to purchase some limit switches and I was going to use a proximity style switch for ease of mounting in my situation. I am confused by NPN and PNP and how that factors into NO or NC. Can someone tell me what I need?
Thanks!
Proximity switches...NPN or PNP?
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Re: Proximity switches...NPN or PNP?
Acorn requires a sinking signal for its inputs, so you need NPN switches. Either NO or NC. NC is usually preferred as they will signal a fault (usually) when defective or suffer from wire damage that opens the circuit. That said, the vast majority of under $50k routers use NO sensors.
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Re: Proximity switches...NPN or PNP?
Thank you, Sir!Gary Campbell wrote: ↑Fri May 28, 2021 10:15 am Acorn requires a sinking signal for its inputs, so you need NPN switches. Either NO or NC. NC is usually preferred as they will signal a fault (usually) when defective or suffer from wire damage that opens the circuit. That said, the vast majority of under $50k routers use NO sensors.