05-31-2014 12:51 PM
hello, WE tried connecting LED to the analog output port of an ni-6008 DAQ card, but the LED didn't glow. Is that because the ports may not be functional? How do we test these ports? We have attached the vi herewith.
05-31-2014 03:14 PM
LEDs are current activated devices and anallog outputs typically can't drive them. Try a digital output, also show the schematic of the hardware you are using to connect to the LED. Is the load resistor correct?
Mike...
05-31-2014 03:22 PM - edited 05-31-2014 03:24 PM
@svans5 wrote:
hello, WE tried connecting LED to the analog output port of an ni-6008 DAQ card, but the LED didn't glow. Is that because the ports may not be functional? How do we test these ports? We have attached the vi herewith.
You did not attach any code.
You need to figure out how much current you can draw from the AO port (I think it has a 50 Ohm resistor). maybe you need some external circuit. Also remember that LEDs are unidirectional. They will only work in one direction, so try to reverse them.
What kind of LEDs are you trying to use? There are tiny ones that draw very little current and there are big ones that can be used as car headlights. 😄
05-31-2014 11:16 PM
thanks a lot!! it worked... 🙂
06-01-2014 01:52 AM
The Labview VI has been attached here. How do we rectify the error being shown? The program uses two water level sensors which give analog voltage signals to the DAQ card. These are then used to turn on or off the relay connected to the motor. In this illustration we're using LEDs at each output.
06-01-2014 02:01 AM
vi is given below
06-01-2014 11:47 AM
You are sending an array of three booleans, but the DAQ assistan3 is only configured for one.
Well, you should probably start with one of the desing templates and do a proper state machine architecture. Why are there so many sequence frames in the sequence structure (For example the execution order of the code in the first three frame is irrelevant, so why chop up the dataflow?)? I would not trap the code with 60 seconds waits. Keep the program interactive!
Sorry, I hate express VIs and dynamic data, because they obscure way too much. I personally don't use them, so I am not sure what you get if an output tunnel uses default if unwired. I would probably use lower level DAQ and more defined datatypes for clarity.