Hi! So It seems each limit switch requires three wires when you can instead achieve the same via the internal pullup resistors in the teensy. See attached image and this link http://johnny-five.io/examples/button-pullup/ Why did you decide to use three wires instead of two ?
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Ahh Ok that makes sense thanks !
The pull-up resistors weren't strong enough to be reliable over a 5 ft ethernet cable, so I opted to do three wires and pull it to ground when the switch is not made. This ended up being the most bulletproof solution that I have found.