Electrical – +24VDC to 5v converter – does the positive make a difference

electrical

I have a fairly general question, but cannot seem to find an answer to confirm my thoughts.

I have a garage motor door, and on the top has 4 terminals – 1 and 2 for a switch button to open and close, 3 is COM, and 4 is +24VDC.

enter image description here

I want to add a little module that will allow me to connect to the garage door and control it. Most modules I can find are 5VDC, and there are some that are 12VDC.

My question is, the garage door states it is +24VDC, does that mean I cannot use a DC converter to change it to 12/5VDC as there is no negative?

I was intending to use something like this: https://www.andymark.com/products/power-converter-12-24vdc-to-5vdc to do the conversion, but the lack of both poles is throwing me especially when the output will be to a USB powered 5V.

This is a diagram from the manual of the circuit board:
enter image description here

Best Answer

"COM" is short for "common". It means ground, or, in this case, negative.

Related Topic