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Gabriel Mendes
21-01-2015, 07:26
Hi everyone, I am having trouble programming a limit switch in labview that when it activates a LED indicator would blink in the front panel, but whenever someone presses it the LED would just stay active or it wouldn't activate at. Does someone know whats wrong with my program?



<--------------Begin-----------><---------------------Teleop-------------->
Open->DigitalInputRefNum set->DigitalInputRefNumget->DigitalInputGetValue->BooleanIndicator(LED)

Thanks, Go Team #1382

Alan Anderson
21-01-2015, 07:43
How do you have the switch wired? It should connect between the "ground" and "signal" pins of a Digital Input on the roboRIO.

Your paraphrase of the program looks okay. We can't tell whether the program itself is correct.

Gabriel Mendes
21-01-2015, 08:06
Thanks Alan it was the wiring, now the program is working properly

Tungrus
21-01-2015, 08:43
Reminder for those using limit switch, do not use 2 pin connector for DIO pins to connect to ground and 5V, its essentially shorting the 5V. Use 3 pin PWM connector and remove the center pin or disconnect the center wire (typically red).

Please correct me if I am wrong.

philso
21-01-2015, 14:02
Make sure you are not using the limit switch as the end stop for your mechanism. They often break when you do that.

GeeTwo
21-01-2015, 22:57
Make sure you are not using the limit switch as the end stop for your mechanism. They often break when you do that.

Correct. You want the load to engage the limit switch as it goes past, not as it slams into the switch.

Ether
22-01-2015, 10:31
Make sure you are not using the limit switch as the end stop for your mechanism. They often break when you do that.

Some teams extend the switch lever with a piece of small flexible tubing. That way the load simply bends the tubing and does not crush the lever.