Solenoid Valve Issue

[spartan3814]

We have our pneumatic solenoids wired, and coded, but one appears to be "shorting" for lack of a better term. It fires one side or the other without command, and the code has been checked. Also, it will not respond to commands. It's a festo and has 12 volt coils. Also, it is hot to the touch. Any help you could offer would be appreciated, after that we can bag our add-on

[spartan3814]

Also, upon command, the lights on the cRIO do not change, and frequently flicker a dim green.

[Tem1514 Mentor]

Getting hot would suggest either wired backwards or the wrong voltage.

You indicate 12 volt coils so have you wired the solenoid bumper to a 12 volt source on the PD and not the cRIO 24 volt rail?

I am assuming you are using the solenoid bumper and not spikes.

[spartan3814]

Originally Posted by Tem1514 Mentor

Getting hot would suggest either wired backwards or the wrong voltage.

You indicate 12 volt coils so have you wired the solenoid bumper to a 12 volt source on the PD and not the cRIO 24 volt rail?

I am assuming you are using the solenoid bumper and not spikes.

The wiring is correct, and we are using the solenoid bumpers. And yes, it is wired to the 12-volt source.
We just did some readings in the pins of our solenoid breakout board, and when the output voltage of said malfunctioning solenoids' pins on the board should be 12, it inly reads 3 volts. This occurrence repeats across all of the even numbered channels on the board, except for channel 4.

[Tem1514 Mentor]

So what is different about number 4 would be a starting point.

Just to check, try removing all the wiring to the solenoids and check your voltages again. Be sure to toggle the outputs and make sure they turn on and off.


As a side note you may also test the solenoids by directly supplying voltage to them. Please use a fused circuit just in case something is really wrong.

[spartan3814]

Originally Posted by Tem1514 Mentor

So what is different about number 4 would be a starting point.

Just to check, try removing all the wiring to the solenoids and check your voltages again. Be sure to toggle the outputs and make sure they turn on and off.


As a side note you may also test the solenoids by directly supplying voltage to them. Please use a fused circuit just in case something is really wrong.

The direct 12 volts made the solenoid function properly.

[Tem1514 Mentor]

Very good that the solenoids works via direct so it tells me that either the bumper/module is bad or your software is at fault.

Have you checked the voltage at the bumper outputs without the solenoids connected? This will give a good idea where to look next.

[spartan3814]

Originally Posted by Tem1514 Mentor

Very good that the solenoids works via direct so it tells me that either the bumper/module is bad or your software is at fault.

Have you checked the voltage at the bumper outputs without the solenoids connected? This will give a good idea where to look next.

The bumpers have been checked and function properly

[Tem1514 Mentor]

When you say the bumper functions correctly is that with a voltage output check only with the software toggling the outputs?

[Tem1514 Mentor]

Please do an OHM resistance check on all the solenoid coils.

I just re-read your OP, what green light flickers?

Oh, something else just came to mind. Do you have the solenoids plugged in correctly? Example, is ground at ground and voltage at voltage. Just have to ask as I saw it once before.

Good luck with your problem. I hope you find it as I'm login off now.

[Kevin Sevcik]

Are you sure you have the solenoid module in the correct slot on the cRIO? If you have a 4-slot, it should be in slot 3 or 4, in an 8-slot it should be in 3 or 7