GPIO dry contact output Python progamming help?

[Gold King]

Hi, I have a motor that can be driven when its two terminal is connected.
The dry contact here means the motor does not start when it's NO (Normal Open) between the two terminals,
but starts when it's closed/connected.

So how can I programm the GPIO output to work on dry contact via Python?


Thanks in advance.

[deepo]

The RPi GPIO outputs are designed to either turn on or off, i.e. with a volt-meter you read +3.3V or 0V on an output. They are not dry contacts.
So my guess is that you'll need to drive a relay with GPIO and then connect the motor control wires to that relay.

There are two guides here, I don't know if you know them:
https://www.raspberrypi.org/documentati ... /README.md
https://projects.raspberrypi.org/en/pro ... -computing

/Mogens

[LTolledo]

definitely you'll need a relay for this....
there are lots of samples in the forum on how to properly wire up a relay and use a program to control it (some even have sample codes)

you may ignore this if you want and do "what you believe is right"....
just accept the consequences of your action

[rpdom]

One important thing to consider is what rating the "dry contacts" (in this case a relay board) need to be.

Check the current rating and voltage to make sure it is safe to switch that load.

[boyoh]

More information is needed on this project
1 Size of motor Voltage Amps( hp) DC or AC
2 Voltage and current rating of the relay
3 Your program must be fail to safe

Regards BoyOh