Compressor With Spike Problems

[RyanN]

Does the green LED next to the relay ports on the DSC light up when you enable the robot? Since your compressor relay is on port 1, the port 1 green LED should light up.

If it is on, try reseating the PWM cable into the Spike. I was helping Team Combustion last year and they couldn't get the Spike to work. This was ultimately the problem, as the cable can seem plugged in, but actually misses the female socket inside of the Spike.

If it is off, check your code (post it if you would like with screenshots), and check the wiring of your pressure switch.

Since you're overrriding the pressure sensor right now, my guess is the cable isn't seated properly.

Please answer the first question though. That will help us all out trying to figure out your issue.

[yogiyogi]

Originally Posted by RyanN

Does the green LED next to the relay ports on the DSC light up when you enable the robot? Since your compressor relay is on port 1, the port 1 green LED should light up.

If it is on, try reseating the PWM cable into the Spike. I was helping Team Combustion last year and they couldn't get the Spike to work. This was ultimately the problem, as the cable can seem plugged in, but actually misses the female socket inside of the Spike.

If it is off, check your code (post it if you would like with screenshots), and check the wiring of your pressure switch.

Since you're overrriding the pressure sensor right now, my guess is the cable isn't seated properly.

Please answer the first question though. That will help us all out trying to figure out your issue.

There are no LED's in the DSC at any time(in the relay area.)
BTW, Our compressor is not connected to any tube or pressure switch or nothing, It should still work right?(It works when we plug it directly to a batterty)

[RyanN]

Originally Posted by yogiyogi

There are no LED's in the DSC at any time(in the relay area.)
BTW, Our compressor is not connected to any tube or pressure switch or nothing, It should still work right?(It works when we plug it directly to a batterty)

If you don't have your pressure sensor connected (electrically), it will not run.

The pressure switch is a normally closed switch, meaning, in a normal state, it will close (make a connection) to both sides of the switch, causing current to flow from one side of the pressure switch to the other. Because of this, you must have it plugged into the DSC in order to work.

If you do not have any LEDs on your turning on in the relay area, that means you most likely have a software issue.

Can you post your code? Include the begin code, and wherever you're switching the compressor on.

If you want to debug your code, make sure you're using the same reference name throughout your code. Compressor and Compresor are not the same, also Compressor and compressor are not the same. The reference name is case and spelling sensitive. If they are not EXACTLY the same, it won't work.

If you're using the compressor start block, you have to use the compressor start VI to enable the compressor. You cannot use the Open Compressor and then use the Relay Set function.

So yea... if you're still stuck, post some code up and let us have a look. As a hint, you can use Snipping Tool in Windows Vista, 7, and I think 8. You can also just 'copy' your code (Ctrl + C) and paste it into Paint to copy just the code you want to share. You can select multiple items in LabVIEW by holding down the Shift Key and Left Clicking your mouse button, or Click-n-dragging a selector to the code you want to select. Be sure to select the wires as well... it's hard to debug if you don't have wires in your screen shots.

[yogiyogi]

Originally Posted by RyanN

If you don't have your pressure sensor connected (electrically), it will not run.

The pressure switch is a normally closed switch, meaning, in a normal state, it will close (make a connection) to both sides of the switch, causing current to flow from one side of the pressure switch to the other. Because of this, you must have it plugged into the DSC in order to work.

If you do not have any LEDs on your turning on in the relay area, that means you most likely have a software issue.

Can you post your code? Include the begin code, and wherever you're switching the compressor on.

If you want to debug your code, make sure you're using the same reference name throughout your code. Compressor and Compresor are not the same, also Compressor and compressor are not the same. The reference name is case and spelling sensitive. If they are not EXACTLY the same, it won't work.

If you're using the compressor start block, you have to use the compressor start VI to enable the compressor. You cannot use the Open Compressor and then use the Relay Set function.

So yea... if you're still stuck, post some code up and let us have a look. As a hint, you can use Snipping Tool in Windows Vista, 7, and I think 8. You can also just 'copy' your code (Ctrl + C) and paste it into Paint to copy just the code you want to share. You can select multiple items in LabVIEW by holding down the Shift Key and Left Clicking your mouse button, or Click-n-dragging a selector to the code you want to select. Be sure to select the wires as well... it's hard to debug if you don't have wires in your screen shots.

How would the pressure sensor will affect the relay/compressor if it is only connected to the DIO?
When does the DSC LED is supposed to turn on?

[Al Skierkiewicz]

yogi,
You need to use the supplied compressor code and connect the pressure switch as stated above. Once you have that, the compressor will turn on when the robot is enabled. The LEDs on the DSC tell you a lot about what is going on there. The three LEDs for power all must be on and bright. The LEDs in the relay area will tell you the status of the relay outputs. (PWM cables do go bad) and the the RSL has an LED (next to the RSL connector) that should flash the same as the big orange light you add to your robot.

[kenfox]

Our programming team got to debug a problem where the compressor wasn't turning on. We tracked it down to a bad spike. The PWM cable was really loose fitting into the spike--we didn't have time to figure out what part of the spike was bad, but those cable connections don't seem very robust.

Here's how we debugged:

1. verify software matches physical wiring
2. verify compressor runs by hooking it to battery
3. verify bus voltage at the spike
4. verify pressure switch works by watching switch with multimeter while the system pressurizes (I didn't know if it was normally open or closed)
5. verify the control signal to spike with signal analyzer (a multimeter would work--it's a PWM cable, but signal is simple on/off not RC PWM)
6. replace the spike

[MrForbes]

Just to add a little more fun to the thread, we had a similar problem with our compressor not running, it turns out we had a bad relay channel on the digital sidecar. This was on our prototype robot, using an old digital sidecar. Usually this won't happen with new parts....but you never know!

[chris.boyle]

We kept having the same problem. It was very intermittent. Sometimes the compressor would run, sometimes not. We swapped out the digital side car and then checked each of the cables to ensure that they were not broken in the middle. In the end we rewrote the Compressor Control loop to something much simpler.

See attachment Compressor.bmp for our code.

The compressor runs correctly now.

Good luck.

[Kevin Sevcik]

All,

It seems like yogi knows he doesn't have a pressure switch and can't use the compressor control loop at the moment. I think he's just trying to get the compressor to run to check out his relay wiring and the compressor. So he's just running the compressor as you would for any other Spike actuated motor. I presume he'll rectify the pressure switch and control loop issues one he gets a pressure switch.

yogi,

If you could upload your Begin.vi and Teleop.vi or post screenshots, that would really help. Other questions: What's your robot signal light doing while you're trying this? Do you have drive code or something that IS working and this compressor relay is the only thing that's not? Do you have 12V power wired to you sidecar? It doesn't really work without power.

[jcbc]

Originally Posted by chris.boyle

We kept having the same problem. It was very intermittent. Sometimes the compressor would run, sometimes not. We swapped out the digital side car and then checked each of the cables to ensure that they were not broken in the middle. In the end we rewrote the Compressor Control loop to something much simpler.

See attachment Compressor.bmp for our code.

The compressor runs correctly now.

Good luck.

Thank you very much for posting this! We have been having intermittent compressor issues with the simplest code and we checked wiring, DSC, modules and breakouts, etc. We will be trying your replacement for the compressor control loop tonight before bagging.

[EDIT] Update after running the code posted by Chris: So far, so good! (Yay!) I want to see it run consistently for another programming session to be certain, but it looks like the WPI compressor control loop VI does not work.