Go to Post Its easier to solve a problem when you have a positive attitude about it. - Arefin Bari [more]
Home
Go Back   Chief Delphi > Technical > Pneumatics
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 11-02-2016, 18:40
Minerbotics4827 Minerbotics4827 is offline
Registered User
FRC #4827
 
Join Date: Feb 2015
Location: Michigan
Posts: 6
Minerbotics4827 is an unknown quantity at this point
Compressor won't turn off - PCM?

This year is our first using pneumatics, and we are encountering an odd problem. When we first set everything up to test, the compressor turned on and off just as it was supposed to, but now that everything has been transferred onto our robot it doesn't. The compressor and pressure switch are both plugged in properly and there is a solenoid opened in the code, but the compressor won't turn off once it reaches the maximum pressure. It actually turns on even when the pressure switch isn't plugged into the PCM. I have already tried updating the firmware on the PCM to both 1.62 and 1.65. If anyone can help us figure out the problem, you'd be amazing!
  #2   Spotlight this post!  
Unread 11-02-2016, 18:53
Anthony Galea's Avatar
Anthony Galea Anthony Galea is offline
Formerly known as 3175student17
no team
Team Role: College Student
 
Join Date: Aug 2012
Rookie Year: 2013
Location: Riverview, Michigan
Posts: 583
Anthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant futureAnthony Galea has a brilliant future
Re: Compressor won't turn off - PCM?

Have you checked your pressure relief valve (the one with the hole/holes) to see if it is letting air out before the pressure switch can trigger? If not, that might be one reason. But that is really weird if the pressure switch is disconnected and it still runs. If it isn't the relief valve, I would guess that you might have a faulty PCM.
__________________
2013-2016: FRC 3175 Knight Vision, student
2014 Center Line District Finalists with 815 and 280
2016 Woodhaven District Winners with 3604 and 6116
2017-?: Rose-Hulman Institute of Technology
  #3   Spotlight this post!  
Unread 11-02-2016, 21:14
rich2202 rich2202 is offline
Registered User
FRC #2202 (BEAST Robotics)
Team Role: Mentor
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Wisconsin
Posts: 1,148
rich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond reputerich2202 has a reputation beyond repute
Re: Compressor won't turn off - PCM?

Quote:
Originally Posted by Minerbotics4827 View Post
It actually turns on even when the pressure switch isn't plugged into the PCM.
Try a new PCM. If there is no switch, then the it should not turn on.
  #4   Spotlight this post!  
Unread 11-02-2016, 21:22
Jon Stratis's Avatar
Jon Stratis Jon Stratis is offline
Electrical/Programming Mentor
FRC #2177 (The Robettes)
Team Role: Mentor
 
Join Date: Feb 2007
Rookie Year: 2006
Location: Minnesota
Posts: 3,735
Jon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond reputeJon Stratis has a reputation beyond repute
Re: Compressor won't turn off - PCM?

Quote:
Originally Posted by rich2202 View Post
Try a new PCM. If there is no switch, then the it should not turn on.
I'll echo this. Also, contact CTRE about it - this is a bad/dangerous failure mode for the PCM, and they may want to investigate why it's acting this way.
__________________
2007 - Present: Mentor, 2177 The Robettes
LRI: North Star 2012-2016; Lake Superior 2013-2014; MN State Tournament 2013-2014, 2016; Galileo 2016; Iowa 2017
2015: North Star Regional Volunteer of the Year
2016: Lake Superior WFFA
  #5   Spotlight this post!  
Unread 11-02-2016, 21:49
Hadi379's Avatar
Hadi379 Hadi379 is offline
Registered User
FRC #0379
 
Join Date: Jan 2007
Location: Girard
Posts: 162
Hadi379 is a splendid one to beholdHadi379 is a splendid one to beholdHadi379 is a splendid one to beholdHadi379 is a splendid one to beholdHadi379 is a splendid one to beholdHadi379 is a splendid one to beholdHadi379 is a splendid one to behold
Re: Compressor won't turn off - PCM?

Check the power wires to the compressor and pressure sensor where they connect to the pcm, we had a similar issue caused by exposed wire contacting at the pcm
  #6   Spotlight this post!  
Unread 11-02-2016, 23:56
GeeTwo's Avatar
GeeTwo GeeTwo is offline
Technical Director
AKA: Gus Michel II
FRC #3946 (Tiger Robotics)
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Slidell, LA
Posts: 3,564
GeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond repute
Re: Compressor won't turn off - PCM?

I agree - check for swarf (metal shavings) or another source of a short across the pressure switch terminals. If you can't find anything, replace the PCM, preferably working with the vendor or CTRE.
__________________

If you can't find time to do it right, how are you going to find time to do it over?
If you don't pass it on, it never happened.
Robots are great, but inspiration is the reason we're here.
Friends don't let friends use master links.
  #7   Spotlight this post!  
Unread 12-02-2016, 00:02
ratdude747's Avatar
ratdude747 ratdude747 is offline
Official Scorekeeper
AKA: Larry Bolan
no team
 
Join Date: Feb 2009
Rookie Year: 2008
Location: Madison, IN
Posts: 1,063
ratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond repute
Re: Compressor won't turn off - PCM?

Another thing to check: make sure the pressure switch isn't shorted out; with the compressor running, unplug the switch. If the compressor keeps running, it's a PCM issue (or swarf intrusion as some have mentioned). If not, the switch or its wiring is shorting out.
__________________
Dean's List Semi-finalist 2010
1747 Harrison Boiler Robotics 2008-2010, 2783 Engineers of Tomorrow 2011, Event Volunteer 2012-current

DISCLAIMER: Any opinions/comments posted are solely my personal opinion and does not reflect the views/opinions of FIRST, IndianaFIRST, or any other organization.
  #8   Spotlight this post!  
Unread 12-02-2016, 19:09
Minerbotics4827 Minerbotics4827 is offline
Registered User
FRC #4827
 
Join Date: Feb 2015
Location: Michigan
Posts: 6
Minerbotics4827 is an unknown quantity at this point
Re: Compressor won't turn off - PCM?

We have unplugged and replugged everything in three times, checking for shorts every time. We didn't find any metal shavings, and even took the PCM apart trying to find any. Even if we unplug the pressure switch while the compressor is running, the compressor stays on. We are ordering a new PCM to test tonight. Until then, we have the pressure switch plugged in as a digital input and are controlling the compressor through code in teleop while we test.
  #9   Spotlight this post!  
Unread 12-02-2016, 20:31
GeeTwo's Avatar
GeeTwo GeeTwo is offline
Technical Director
AKA: Gus Michel II
FRC #3946 (Tiger Robotics)
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Slidell, LA
Posts: 3,564
GeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond repute
Re: Compressor won't turn off - PCM?

Quote:
Originally Posted by Minerbotics4827 View Post
Until then, we have the pressure switch plugged in as a digital input and are controlling the compressor through code in teleop while we test.
Don't forget that for competition you need to either switch back to a PCM or put the compressor on a spike (R88 C and D).
__________________

If you can't find time to do it right, how are you going to find time to do it over?
If you don't pass it on, it never happened.
Robots are great, but inspiration is the reason we're here.
Friends don't let friends use master links.
  #10   Spotlight this post!  
Unread 12-02-2016, 23:32
ratdude747's Avatar
ratdude747 ratdude747 is offline
Official Scorekeeper
AKA: Larry Bolan
no team
 
Join Date: Feb 2009
Rookie Year: 2008
Location: Madison, IN
Posts: 1,063
ratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond reputeratdude747 has a reputation beyond repute
Re: Compressor won't turn off - PCM?

Quote:
Originally Posted by Minerbotics4827 View Post
We have unplugged and replugged everything in three times, checking for shorts every time. We didn't find any metal shavings, and even took the PCM apart trying to find any. Even if we unplug the pressure switch while the compressor is running, the compressor stays on. We are ordering a new PCM to test tonight. Until then, we have the pressure switch plugged in as a digital input and are controlling the compressor through code in teleop while we test.
Yeah, I'd RMA that PCM. That's clearly a PCM issue.
__________________
Dean's List Semi-finalist 2010
1747 Harrison Boiler Robotics 2008-2010, 2783 Engineers of Tomorrow 2011, Event Volunteer 2012-current

DISCLAIMER: Any opinions/comments posted are solely my personal opinion and does not reflect the views/opinions of FIRST, IndianaFIRST, or any other organization.
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 05:31.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi