Ok. Jazz
I know what you mean by using one sensor:
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So far I use 2 sensors, one is limit +, other is Home and limit- all in one, connected like that:
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I think this is your option#3 " uses 2 inputs and 2 types of switch. NC wired in series for limits on one input. NO wired in parallel for Homes on other input"
I was wonder how you get away with having only one sensor, must use soft limits in Mach for safety. I've seen 3 sensors solution: limit+ limit- and home in one axis, but I think is not needed.
Correct me pls. if we I am wrong.