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tait
22-02-2010, 19:00
My team is having a problem; we are using the festo that came in the 2010 kop and we can't get it to fire remotely. Manual override works fine, we also connected it to the 24v output in the cRIO, but still the piston won't fire remotely. Any ideas? Also, we are using labview. Any and all help on this subject would be greatly appreciated.

waialua359
22-02-2010, 19:35
Sounds like the same problem that a team here in Hawaii was having.
We gave them our Festo, but never followed up with them.
I'll ask them to follow up.
Hopefully, you get an answer before we do.

DonRotolo
22-02-2010, 21:42
Is one of the 8 green lights on the solenoid module on? If not, then your code is not commanding the solenoid on.

tait
22-02-2010, 22:18
No, none of the green lights are on. We are setting the solenoid set vi with a single button from the joystick. Can you please help me fix the code, or give me an example screenshot?

kavisiegel
22-02-2010, 22:22
Here's some sample code

Ted Weisse
22-02-2010, 22:23
Do you have the bumper wired for power from the PD?

tait
22-02-2010, 22:26
Thanks, i'll let you know if it works.

What is the DIO for in the begining?

tait
22-02-2010, 22:27
Do you have the bumper wired for power from the PD?

Yes, its already connected to the 24v output in the PD

kavisiegel
22-02-2010, 22:29
Thanks, i'll let you know if it works.

What is the DIO for in the begining?

Ignore that, it's our limit switch for our arm so we don't lift too high. I meant to delete it in that screen shot.

Our big problem was that we weren't initiating one side with true or false, so they both remained false no matter how many times we tried to flip them. Hope it helps.

tait
22-02-2010, 22:37
your example shows us the true value of the boolean, is it possible that you could show us the false? Much appreciated
where did you get the execute on rising edge?

kavisiegel
22-02-2010, 22:44
your example shows us the true value of the boolean, is it possible that you could show us the false? Much appreciated
where did you get the execute on rising edge?

On initiation, or in the second VI?

On initiation you want one of the 2 sides to be set to true. Wherever you want the default state of that piston to be, set it to true.

In the second VI, what it does is read one of the 2 sides. Specifically, the arm minus side. If that's true, it sends that true to the arm plus side and inverts it to a false that it sets its self to. Basically, all it does is switch sides.

The execution on rising edge, that was posted in the LabVIEW form a week or so ago. The arrow that looks like an equals sign is called "Implies" and can be found in the boolean group of functions

waialua359
22-02-2010, 22:48
Sounds like the same problem that a team here in Hawaii was having.
We gave them our Festo, but never followed up with them.
I'll ask them to follow up.
Hopefully, you get an answer before we do.
Another team here had the same problem and checked the voltage. The wiring was poor where they were getting 23.x volts. It was enough to turn on the LED but not enough to fire. Also, do you have active pressure, otherwise, I believe it wont even work or click.

tait
22-02-2010, 22:48
did you guys wire the signal on the solenoid connection?

Al Skierkiewicz
22-02-2010, 22:55
A simple check for 12 volt valves is to wire externally a 9 volt transistor battery. You should see the led light and you should hear the solenoid click even with no air. Sometimes it is just a bad valve.

tait
22-02-2010, 23:03
I dont have a nine volt battery but thanks for the idea. we wired the red cable with the red and the black with black. Do we have to wire the black one with a signal and the red one to ground? The watcdog is not ffed at some point in the previous code. What is the watchdog; what purpose does it have?

whytheheckme
22-02-2010, 23:04
Just a thought, is your solenoid card in Slot 7? It needs to be for 24v to work. Even after changing it to slot 7, you need to change your code (the default uses slot 8)

Jacob

tait
22-02-2010, 23:36
our solenoid card is in slot 8, but the FESTO's lights wont turn on.

Al Skierkiewicz
23-02-2010, 07:45
I am going to let someone with more expertise on that explain the watchdog. It must be fed is all I can say. The red wire connects to the positive battery terminal and the black to the negative terminal if you are trying to check the valve. I believe the valve will still function if you reverse the leads but the LED will not come on.