Q: I occasionally have a situation in which one of the conductors in a cable run is cut by a staple. The walls are already up and it would be murder trying to run another length of cable. Any suggestions?
A: Alarm panels often use common grounds in their alarm loops. So if you are short an extra wire you can share that common ground with one wire instead of two and free up an extra wire. Check with your panel manufacturer. They may be able to tell you where you can double up. I have even gotten an extra wire to set up an additional PIR or glassbreak without having to run extra wiring. Hope this helps.
Q: I need to install an extra PIR for a customer. The only thing I have in the area is an NC alarm loop for a door. It will be very hard getting power to this area and I do not want have to go wireless. Is there a PIR that has it’s own power but is hardwired?
A: You are in luck. One PIR that comes to mind is the Optex CX50R/60R/70R series. This PIR can be powered by a 9V lithium battery and wired directly into a NC or NO alarm loop. It only draws 20 uA and will operate for up to 4 years on a 9V lithium battery.





