switch control

[soundofwind]

How can i achieve the control of some switches through the use of NI 6218 card and labview? Should I use the digital I/O channels and how? Is it the correct way that i make some virtual switch in labview and connect them with the NI digital IN channel. Then the real switches are connected with the corresponding NI digital OUT Channel? Thanks:smiley

[Dennis_Knutson]

Yes, you can control a switch/relay with a digital output. Depending on the specs of the relay, you may need to amplify the current or do a voltage level shift in order to drive it.

I have no idea what you mean by 'virtual switch' and why you would even care about the digital inputs. You simply set the digital output high or low.

[soundofwind]

I mean the boolean switch in the labview program. I have to use the it to control the  digital output high or low, don't i? Should I create a channel, and set it as the digital output? can you send me an example or sth, please?thanks a lot

[Dennis_Knutson · Accepted solution]

Here's a couple of ways to do a basic digital output. Alos look in the shipping examples (Help>Find Examples) and give a look at the DAQmx Getting Started.

Message Edited by Dennis Knutson on 01-07-2009 09:05 AM

[soundofwind]

thank you so so much

[Rev]

I believe I am trying to do something similar, but I am confused.  Any help would be appreciated.

I have an SCB-68 DAQ to which are tied 4 relays by way of transistors.   (DAQ Digital out pin -> transistor -> relay -> load)

I want to "activate" the transistor to trip the relay.  I.e., I need to hold high (+5V) at the transistor for as long as I want the relay to stay shut.  Initially, I will just want to use switches on my LV front panel to operate the relays (press button to go high...press again to go back low).

This seems very basic, but I am just not seeing how to send a continuous high or low as an output.  Unless I just can't see the forest for the trees, I don't believe any examples that ship with LabView or any examples of this great forum show an example of this exact scenario...

Can someone provide one?

Thanks very much,

-Rev