electrical & pneumatics help

[samir13k]

I am trying to connect an old bot up with the new controller, and i am having trouble with the pneumatics. The nason pressure switch says "C" and "NC". These have to connect to digital I/O, but i need to know which one is +,-, or Signal. I had it working, but the wire had gotten hot. Can you tell me what the C and NC plug into.

thanks

PS, I am supposed to use PWM for this right?

[EricVanWyk]

Originally Posted by samir13k

I am trying to connect an old bot up with the new controller, and i am having trouble with the pneumatics. The nason pressure switch says "C" and "NC". These have to connect to digital I/O, but i need to know which one is +,-, or Signal. I had it working, but the wire had gotten hot. Can you tell me what the C and NC plug into.

thanks

PS, I am supposed to use PWM for this right?

Samir -

What wire is getting hot? How did you wire into the Digital Side Car?

The GPIO is very similar to what you may be used to from previous years. The pins are:
Signal
5V
Ground

The signal line has a weak (10k) pull-up to 5V, so it will report "1" until something tells it not to. You can therefore wire a switch-like sensor between the signal and ground lines. When the switch is closed, it will force the signal line to ground and report a "0".

[samir13k]

I just wired it into the digital sidecar through the digital I/O port. Can you tell me what C and CN are. I used PWM to wire it, but that is what was getting hot. I believe only 2 wires of the PWM are used, but i need to know which ones. Whether it is pos/neg, neg/sig, or pos/sig

[MrForbes]

C is Common, NO is Normally Open, NC is Normally Closed. Connect the negative (black) to C and the signal wire (white) to NC, and do not connect the positive (red) wire.

If you connect the black and red wires to a switch, the wires will get hot. This is not recommended, it's what we call a "short circuit"

[samir13k]

K thanks, that should help.