LabView and Relay Controls

Your post is a little unclear. Unless you really know a fair amount about computers and electronics, I doubt you are going to be able to build the I/O interface board that LabView needs to communicate and control devices (assuming that all you have is the LabView software only). You need to buy a LabView I/O interface card at the very least, and I would suggest a relay module that fits onto the interface card (rather than trying to wire a standard relay into the LabView interface card somehow).

The interface card and modules are a little expensive, but LabView is a professional SCADA program after all (we use it here for our on site lab). Other manufacturers do make cheaper LabView hardware that may be a less expensive option. If you only have a simple application (and got the Labview program for free), you may want to consider shareware and freeware control programs that allow you to interface and control devices like relays using the computers serial or parallel ports instead.

If you are actually talking about building the main Labview control card that fits directly to the motherboard (not the I/O interface board), then forget it.

LabView is only a software which does control a lot of devices equipped with an appropriate drivers (LabView compatible). It's presumed that any simple relay couldn't be connected to LabView interface directly but through such a compatible device. Those devices might be imlemented as a PC boards(TI or any other brand), modules connected to PC ports (com, LPT, usb etc). For instance you can use any TI PCB with D/O (digital output with open collector). State of D/O(ON/OFF) might be controlled by timer program created in LabView IDE. Then that D/O in its turn should switch a relay in ON/OFF state when timer reaches up a desired number of countings.

Hi all thanks for the answer.

I had got the answer myself after doing some research.

I am going to bulid a relay switch using parallel port as communication port. Relay powered by DC.

Program will be written in Labview command to activate the relay through a transistor array.

:)

DC,

I need to do something just like this to control a relay also...

Could you send me your Labview code, and how you did this? I would really like to use a parallel port as an output rather than buy another DAQ card, just like you did.

Thanks!

JC