Compressor start issue

Technical Pneumatics
1

Our compressor will turn on for half a second and reboot the Roborio.
We have tried modifying code, swapping pressure switch, swapping compressor. It was functional last year and we can not determine what is different from last year.

Power to Compressor:
Battery --> PDP --> VRM --> PCM --> Compressor

Using CAN to PCM.
Pressure switch is connected to PCM.
We are using 18 awg wire from PCM to Compressor.

We are using Labview.
Function Solenoid response from our solenoid code.
We do not have Compressor code because we only care that it is on when the robot starts and the compressor shuts off when the pressure switch is tripped.

PCM shows Green status light but no compressor light.
Occasionally the Status light is yellow.
Self-Test shows that it is probably a compressor short, but this sticky fault is inconsistent.

Any help or resources to solutions would be appreciated. Thanks.

2

The PCM should not be connected to the VRM. It should be connected directly to the PDP.

3

Thank you for a quick response. Of the 100 things we tried, we didn’t check the most obvious.

4

Our team is dealing with the same problem. We Can’t get 16 Gage wire to fit inside of the PCM. The wire on the compreser is 16 Gage wire so do we use 16 Gage wire or something diffrent Gage?
Thx.

5

You could make an adapter to 18AWG (minimum allowed by the rules). 16AWG is the maximum size for the PCM.

6

Thx. AusticShalit

7

I highly recommend wire ferrules. I have used CTRE’s, but any should work well. They make plugging into weidmuller connectors much easier and prevent any strands poking out.

EDIT: Look here for an example.

8

Also, make sure your PCM isn’t faulted.

9

As crazy as this sounds, if the pcm is near the radio the pcm will throw sticky faults. That took us a while to understand why the compressor wouldnt work for us several weeks ago but as soon as we moved the radio away we havent had a problem since

10

If you haven’t already, check that pressure switch isn’t wired backwards.
Also, are you using the pressure switch from the KoP or something else?

11

The pressure switch cannot be wired backwards. It doesn’t have a forwards or backwards, it’s just a switch. That’s why there is no polarity coloring on the PCM connections for the switch.