Relay module and DAQ Assistant

Hi everyone!
I'm a Labview beginner and currently dealing with a priori easy business. Recently I got a USB Relay Module to be incorporated in an alarm system. Let's say if one gets a certain value bigger than other, the relay should close and activate a siren (see example attached). For this I've used the DAQ assistant and configured one of the module output channel. By using a simple boolean switch, I can easily close and open the relay. However, if I use a case structure, an error is obtained, as the DAQ Assistant for one output can be only used once. I mean, if the relay is closed and I'd like to get back the original situation, i.e. opened relay, what should I do?
Schematically:
-if A>B, then closed relay
-if A<B, then opened relay
Sorry for the messy explanation, but I think you get the point.
Thanks in advance
Solved!
Go to Solution.
Attachments:
alarm test.vi ‏44 KB

I just got it. The problem was that in the main vi, not in the example I attached, the same output via DAQ Assistant was configured for two different case structures. Obviously the relay module was going completely mad, since I had two independent pairs of TRUE and FALSE working at the same time. If I get, for instance, TRUE for one case structure and FALSE for the other, the switch doesn't know what to do. Hope now it's clear...

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Edit.
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is_this_what_you_meant.jpg ‏212 KB

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labview12110 wrote:
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AFLR wrote:
A very simple problem...
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This is my first time on here and I've only been using this software for a couple of days so it's possible I'm making a trivial error but I thought I'd post here anyway as I can't find anything on the net about my problem.
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Attachments:
Tare function and restart.vi ‏365 KB

I solved my problem with the tare function, i used a case structure and shift register to store values in it. se picture below.
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Attachments:
tare function.png ‏25 KB
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