On Fri, 01 Jun 2012 13:03:24 +0100, Jim K wrote:

I've just bought a 12vdc alarm quad PIR (as suggested earlier in the
thread), seems I'll be back as the spec says "alarm" will output 24vdc
yet the IP camera I/O is rated at 5vdc ;#

How does the "alarm" output generate 24v from a 12v supply?(*). Are
the contacts "voltage free"? I suspect that 24v DC is the maxium
rating they can switch rather than there being 24v present.

What is the camera expecting? Just a switch/contact closure across a
couple of terminals/pins or a voltage? If a voltage that is almsot
certainly going to be available from the camera.

(*) Yes, it could have DC-DC convertor but not very likely in a PIR.

--
Cheers
Dave.