Proximity Switches

**paulus.v** · 22-10-2013

If I use them only for homing with additional limit micro-switches will I have any issues being PNP?

**EddyCurrent** · 23-10-2013

PNP is the most common type used so you should have no issues.

Technical FAQs | Knowledge Base

yours are 5-10v so you should not require extra resistors as in this discussion but it makes interesting reading
http://www.mycncuk.com/forums/genera...-required.html

**irving2008** · 23-10-2013

@paulus:
You can't use the 2-wire ones directly, they need additional circuitry ( see here for more info)

Here is a diagram showing how to use the 3-wire ones

Click image for larger version.

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@EddyCurrent - not sure I agree PNP are more common...

**JAZZCNC** · 23-10-2013

Originally Posted by irving2008

@EddyCurrent - not sure I agree PNP are more common...

No me either.!!. . . . Must took the thoughts straight from my Mind. .

**EddyCurrent** · 23-10-2013

Originally Posted by irving2008

@EddyCurrent - not sure I agree PNP are more common...

Mabe on the other side of the pond.
Not arguing because it doesn't matter but;

I've just done an inductive proximity sensor product search on Pepperl & Fuchs website
No. of products NPN 74
No. of products PNP 207

Same again but RS online
No. of products NPN 54
No. of products PNP 208

Edit: Just noticed the 2 wire ones are NAMUR type, this is quite a good document
http://www.simeks.biz.tr/resimler/pd...ciklamalar.pdf
Maybe the last time I used them (which is quite a number of years ago now

) the PLC had input cards designed for them, although I've never been a fan of 2 wire type.