Which Type of Limit Switch

[Neale]

Looking at the one I have, the key thing about it seems to be duplication. There are effectively two relays which can be wired in parallel or, ideally, driven via a double-pole e-stop switch. Then the relay n/o contacts are in series so either relay dropping out will open the circuit. It's a bit more complicated than that, of course, depending on which model relay you get, but that's the heart of it and how it can reasonably claim to be a "safety" relay. I guess that build quality is better than a cheap relay from Maplin as well.

[cropwell]

Thanks Neal,

I'll only take issue with one thing, I find 'cheap' and 'Maplin' don't sit easily in the same sentence.

Rob