Air Compressor not turning off.
 

Maybe some of you experience team out there has this issue.

We have a pneumatic setup everything work except that the
compressor is not turning off. The manual indicate somewhere that this year we do not need to include compressor control in the programming, the PCM should handle that.

Veteran teams out using pneumatics, what do you find to be true?
Is our problem a programming issue?

Re: Air Compressor not turning off.
 

Do you have a pressure switch wired in?

Re: Air Compressor not turning off.
 

Did you plumb and wire the pressure switch correctly? Does the compressor continue to run after the pressure significantly exceeds 120 psi (ie 130+ psi?). Is the compressor and pressure switch wired to the PCM?

Re: Air Compressor not turning off.
 

It's almost certainly not a programming issue. Something may be wrong with the pressure switch. Have you verified it's functioning properly.

Re: Air Compressor not turning off.
 

Can we get a picture of the setup of the wiring and everything else. We may be able to spot issues.

Re: Air Compressor not turning off.
 

We ran the sample code and tested the cylinder and work fine. But we noticed the compressor is not turning off. The pressure switch and compressor are both wired in PCM.

How do we wire the pressure switch correctly? I understand that it is not polarized.

I will try to get in a pic for you. Any of you using pneumatics this year?

Re: Air Compressor not turning off.
 

Yeah it was about 135 psi and didnt turn off.

Re: Air Compressor not turning off.
 

We plan to be, but we probably won't have the system in a testable state for about a week.

Re: Air Compressor not turning off.
 

Do you have a gauge to check the pressure? If it is over 120 something is wrong. If you have a leak it might never get to 120. Or if you have a rediculous amount of storage it would take a while to reach full pressure.

Ours ran, filled up, and shut off just as it should

Edit: try another pressure switch or double check the connections on the pressure switch. If wires are shorted it will continue running. Look for loose strands at the PCM connections.

Re: Air Compressor not turning off.
 

We haven't decided yet. We were about to get pneumatics working today but we couldn't connect to the robot to test.:mad:

Re: Air Compressor not turning off.
 

I second the request for wiring pictures. Did you try a difference pressure switch?

Your system should never allow you to get that high. Where was your emergency relief valve?

Re: Air Compressor not turning off.
 

The relief valve commonly doesn't bleed air until 130-135 anyway.

Re: Air Compressor not turning off.
 

We had the exact same issue today. Swapped out the pressure switch, triple-checked everything and it still didn't turn off. We finally tried a different PCM that hadn't been updated and it worked! Compressor switched off as expected. The firmware version of the working PCM was 1.60 and the version that did not work was the newer 1.62.
:confused:

Re: Air Compressor not turning off.
 

It's required by the rules to bleed at 125 psi. If yours doesn't, you need to adjust it.

Re: Air Compressor not turning off.
 

We had this same problem today. We discovered that the newest version of the firmware causes this problem. We reflashed back to the previous version and the pressure shutoff switch now works properly again.

To troubleshoot, completely disconnect the pressure switch from the pneumatics module. This should cause the compressor to shut off. (Fail safe) If it keeps running, it's not the switch, it's the firmware.

Re: Air Compressor not turning off.
 

Ours is updated but we haven't tested it yet; I'll hook a compressor up it tomorrow and see what happens.

Also, has anyone from FIRST seen this thread, it looks like this might be a major problem.

Re: Air Compressor not turning off.
 

Sorry to hear that. What seems to be the issue?

Re: Air Compressor not turning off.
 

Were not entirely sure. I haven't had a ton of time to dive into all of the documentation so I have been going off prior knowledge.

We have set up our control system and router correctly (we think). But when we try to connect to the D-link the computer says it is connected to the network but the driver station says it isn't.

I have a feeling if I look at the documentation I may figure out what I'm missing.

Re: Air Compressor not turning off.
 

This is a picture of our test. Hopefully you can make out the controls.
We might try swapping the pcm and see what happens

Re: Air Compressor not turning off.
 

We swapped the pressure switch and found the same issue. We will try to
swap the pcm now and see what happens.

I will let you know tomorrow.

Re: Air Compressor not turning off.
 

That is always a good start. just make sure you download FRC 2015 update suite before doing anything else. We have a new programmer this year. He is doing a great job. since we have new controls I make sure he goes through the process step by step.

Ours won't even turn on!!

Re: Air Compressor not turning off.
 

Yes we did and it is over 120 psi. We have one tank onboard.

Re: Air Compressor not turning off.
 

It could be the firmware. Is the working firmware the 1.6 version? How would get to a previous version?

Re: Air Compressor not turning off.
 

Hang in there. Do not forget to wire up your CAN cables from RoboRio to PCM to PDP.

Re: Air Compressor not turning off.
 

I just tested ours (with the 1.62 firmware) and it works fine.

Re: Air Compressor not turning off.
 

Okay. I guess this is an issue and needs to be addressed to FIRST.
Something is not quiet right.

Re: Air Compressor not turning off.
 

The changes between 1.60 and 1.62 are slight changes in the status LED. There is no compressor related change between the two.

If your having trouble with your PCM, go to the self-test page of the roboRIO web-page configuration.
Jump to "Self Test"...
http://wpilib.screenstepslive.com/s/...ribution-panel

This will tell you...
(1) -if the PCM is enabled (robot is enabled)
(2)- if the pressure-switch is closed (pressure is not full)
(3)- if the compressor-output is on

(3) requires (1) and (2) regardless of which firmware is used.

Does the compressor turn off when the robot is disabled? If not then it sounds like the compressor ground input is shorting to robot ground somewhere outside of the PCM.

When the compressor is on, is (1),(2),(3) reported in the self-test?

Another easy check is to just disconnect the pressure switch. The PCM has two weidmuller connectors that normally go to the pressure-switch. When the pressure-switch signals not-full, it shorts the two leads together (relay). When the pressure-switch signals full, the two leads are open. So if you short the two BLUE PRESSURE SW. connectors on the PCM with a wire, instead of connecting to pressure-switch, PCM will behave as though the pressure-switch reads not-full. Remove the wire and PCM will behave as though pressure-switch reads full.

Re: Air Compressor not turning off.
 

I do not see this issue. What happens if you remove the wires from the PCM? There may be a short at the PCM connector. PM me and I can call to help troubleshoot.

Re: Air Compressor not turning off.
 

When wires removed the compressor still runs as long as the robot is enabled.
I will PM you as and go from there.

Re: Air Compressor not turning off.
 

How do we get the old version of the firmware (1.60)? We know for sure the pressure switch is good. We did series of tests to isolate it. When we did the self test there was no single instance when the compressor is indicated full.
Right now we will try a new PCM and see what happens. We will try this tomorrow. I will keep you updated.

Re: Air Compressor not turning off.
 

Do you have a solenoid anywhere in your code? Our experience was that the compressor needed that before it would run.

Re: Air Compressor not turning off.
 

We put the firmware version 1.62 back in to reconfirm.
The compressor STILL is not turning off -- while minutes before, the other (v1.6) PCM was working perfectly.

Also, after removing the 2 pressure switch leads from the PCM, we see this:

The self test completed successfully.

PCM is enabled.
Compressor is close-looped on sensor
Comp Is On
Pressure is not full

Checked also for damage, shorts, or stray wire bits, but it's clean.
Other than getting another PCM to try, I don't know what to do next.
Ideas?

Re: Air Compressor not turning off.
 

So judging from the Self-Test the PCM reports that the "Pressure is not full" despite the pressure-switch inputs on the PCM not being wired to anything. That is likely the root cause for WDB's symptom, and not firmware. This sounds like hardware and your "other PCM" likely works regardless of what firm is in it.

To further confirm it's not a firm issue, I put up 1.60 PCM firm (one-dot-sixty) at...
http://www.crosstheroadelectronics.c...ation-1.60.crf
... Flash 1.60 back into your bad PCM and I bet you will still find that the self-test still reads "Pressure is not full" despite having the PCM not connected to the pressure-switch.

For any given functional PCM : When the pressure switch is not connected, Pressure should read as "Pressure is Full", regardless of all other factors. This is deliberate so an unplugged pressure switch causes compressor to stop.

dumbuya, can you do the same check? Unplug the pressure-switch from the PCM and run the Self-Test to see if the pressure still reads "Pressure is not full".

At any rate dumbuya and WDB, I recommend contacting support@crosstheroadelectronics.com for next steps.

Re: Air Compressor not turning off.
 

Confirmed. Reflashed the suspect PCM back to 1.6 and the same behavior was observed. Removing the pressure switch from the PCM should not allow the compressor to run, but it still runs. So it looks like a hardware problem with this specific PCM. Put in our other PCM in and it works perfectly.

We took a picture of the board near the pressure switch contacts and there might be some anomaly there (you'll have to zoom in a little), but we'll get a replacement PCM anyway.

Thanks Omar for your assistance!

Re: Air Compressor not turning off.
 

No matter what test setup we did it shows on the self test " Pressure is not full". We found a fix now by swapping a new PCM and it works as intended.
However, I cannot tell you what we find to be the issue other than to say we might have had bad PCM.

One thing I could try is update 1.6 firmware in the old ( "bad") one and see if it is going to respond as intended.

Thanks for your urgent response to the issue.

Re: Air Compressor not turning off.
 

Thank you to all for sharing your experiences with the PCM.

We swapped the PCM with a new one and it worked as expected.