Using a 12v trigger from a projector

[DavidJ]

Hi, I'd like to use the 12v power-on trigger from my Panasonic projector to turn on a "Now Showing..." light. I get how to turn on the light, but I have a question on the triggering.

 

What device do I need to sense the on/off 12v trigger from the projector? A 2450 IO Linc?

 

Thanks.

[Brian H]

The 2450 I/OLinc can not be triggered by a 12 volt signal.

It needs a closure between the S Sensor Terminal and the GND terminal.

Smarthome does have a Low Voltage Detector Kit. That includes the I/OLinc and a Low Voltage Detector. That should work.

Unfortunately it is showing out of stock.

http://www.smarthome.com/24950A4/I-O-Li ... Kit/p.aspx

 

I have used an Optoisolator to trigger an I/OLinc if you care to create a small interface board to connect to it.

A 12 volt relay could be made to work also. As long as you can determine the safe current the 12 volt signal can provide.

[LeeG]

An I/O Linc Sensor requires GND to activate the sensor. The projector trigger could be hooked to a 12V relay. Then use the relay contacts to apply GND to the I/O Linc Sensor. Do not know if the projector trigger can energize a relay. The projector spec's should provide that answer.

 

An alternative would be to use a Simplehomenet EZIO2X4. It has opto=isolated Inputs which will trigger with clean 12V DC. Again it depends on what the projector 12V trigger really is.

 

The I/O Linc would be the less expensive approach if the projector trigger will energize a relay.

[DavidJ]

Thanks guys! I mis-read the manuals, and was quite surprised when I found 5v across the GND and S terminals.

 

I'll look into the relay or optoisolator approach and give it a go.

[Brian H]

You are welcome.

Calling the Input a Sensor may have not been the best choice.

 

I keep forgetting the some of the Simplehomenet modules have isolated inputs.