UPC20 triggering from n/c PIR?

Andrew Martin

Hi there,
I am running a project where I would like to trigger a UPC20 based on an input directly from a passive Infra-red. The UPC20 looks for a closed contact to trigger, and a PIR is open on trigger. Is there a simple way that anyone knows of for me to place a relay in line that would reverse the n/c to n/o and vice versa?

Anyone had any luck doing this in the past?

Kind regards,

Andrew

ericmedley

You need a dual pole relay and a power supply.

vining

You need a normally closed relay (control voltage not applied). Make sure the control voltage required for this relay is suitable for your PIR contacts. Install a power supply in series with the alarm contact and your relay's control terminals so when the PIR is normal (no motion) voltage is applied to the relay which means the relay's contact will open. When there is motion your PIR's contacts will open in turn opening the voltage path of your relay control voltage and it will return to its normal state of closed (control voltage applied).

Chances are it will be easier to go to Radio Shack and find a relay with both NC and NO terminals with a common to both.

You can't use the PIR on a master's IO port and code to control a master relay port and there by track the motor state? That would be the ideal thing to do.

Andrew Martin

Thank you

Hi there,
Thanks to both of you for the tips. I'll try the relay out later this week - I can see the logic in the way you describe it.

I wish I could do it via the NI masters I/O port - done that before and it is a lot easier. In this case, this area is a little add-on area that we are doing as a favour - and cabling to the NI is near impossible.

Looks like this relay idea will get me up and running though -thank you for takin gthe time to respond. Thats what makes these forums work.

Cheers,

Andrew