Electronic Alarms and Home Security Devices - Need help replacing an OLD motion sensor

Hi all,

I am replacing an approximately 25 year old motion sensor, a visonic MR-3000-PC sensor with a new Ademco Aurora pet immune sensor. The old Visonic sensor had 6 wires going to it with the red and black wires going to the usual positive and negative terminals. There were a green and a yellow wire going to terminals labeled "tamper" and a blue and white wire going to terminals labeled "N.C". I am not sure what N.C is and what the difference is between the blue and white wires that went to the respective terminals. Since the new Aurora sensor does not have a tamper switch and has only 4 inputs I am assuming I need to use just the red, black, blue and white wires, however as I said I do not know if the blue and white wires go to either the "protective loop" or "Closed Circuit" terminals. I am completely stumped and am hoping some one out there may be familiar with this sensor to shed some light. Thanks!

What kind of panel?

You could have bought an aurora-t that has the built in tamper switch, but none the less you will connect the red and black to + and - and the blue and white to the zone terminals aka, "closed circuit protective loop". Depending on the panel you will most likely connect the tamper wires together, or if it is goofy ou may havyou may have to tape the off.

Thanks for the super quick reply kcxj!

It's an old radio shack alarm, but I am just replacing an existing motion sensor. I will be replacing the whole alarm minus the new motion sensor shortly, but only have the time to change this sensor now. Does it matter which one the blue and white wires go to, or can they go to either the closed circuit or protective loop. According to the wiring schematic it looks like terminal 3 is for the protective loop and terminal 4 is for to closed circuit, however I do not know if closed circuit protective loop is a single phrase or if it is broken up to closed circuit and protective loop. The corresponding terminals for the blue and white wires on the Visonic just say N.C, but now I am wondering if the left terminal is labeled "N" and the right terminal is "C". It looks like N.C means normally closed, but I still don't know which wire goes to the closed circuit or protective loop of the Aurora. Thanks again.

You're overanalyzing it. NC just means normally closed. 99% of all alarm loops use normally closed circuits. The power input has polarity, the alarm contact doesn't, it's just a switch. That pair for the tamper loop can be just twisted together, taped and ignored.

Thanks for the help guys! I put the white wire to terminal 3 and the blue to terminal 4 and it seems to be working.