How do I switch a relay then one second later switch it back?

[alanhomer]

I am currently doing an experiment where I need to send a digital output signal to a relay, the relay switches, then one second later switches back. I have connected the relay to the CB68-LP board and I can get it to manually switch when I click, but I need this to be an automatic response.

I just need to click a switch so the relay changes and 1s later changes back again. Any ideas?

[chilly_charly]

So you already did most of the job !
I suppose that you built some kind of a VI, where you can switch the relay upon switching a boolean control. Let's call it "Relay.vi".
One very simple solution :
Build a new VI, with a sequence structure with 4 frames :
in the first frame, put a waiting loop, which will wait until a switch button is pressed;
in the second frame, wire a True boolean constant to your Relay.vi
in the third, place a wait node, and wire a 1000 ms constant to the input
in the forth, place another instance of your Relay.vi, this time connected to a False constant.
It's bot very elegant, but that's the simplest thing that you can achieve.
May that could do to start with ?
More help ?

[Powder]

> I just need to click a switch so the relay changes and 1s later
> changes back again. Any ideas?

Why not just a sequence with three frames. First fram close, second fram
Wait 1s, third frame open relay?

[chilly_charly]

The first frame has to wait until the user decide to close the relay. Of course this can be done when the user press the vi "run" button. But that's a bit different since such a vi could not be run in "Run when opened" mode...

To maintain things very basic, my preferred solution would be to put a 3 frame sequence, inside a case structure, triggered by a "Close Relay" boolean, inside a while loop with a stop button.
How many more refined solutions ?
CC

[Dennis_Knutson]

Why bother with a sequence structure? Use an event structure with a time delay between two relay operations and tie them together with error in/error out.

[chilly_charly]

Hi Dennis !
"How many more refined solutions ?"
That's one !
I knew that somebody should comment about the inopportunity of sequence structures !
:-))