Hi,

I'm installing a Melcom ST6100 to replace an old control panel that has reached the end of its useful life. I decided at the same time to replace the PIRs with Melcom's own, as the existing ones were a mixture of all sorts.

I carried out the pre installation test as described in Melcom's Installation manual, and everything seemed to be working fine. So I then connected a new PIR on a short length of new cable, as the previous alarm was only 4-core, with no tamper circuit on the PIRs. The 12v + and - were connected to Aux1 + and -, the REL terminals to Z3, and the tamper terminals to TAMP. The PIR failed to light (yes, I checked the jumper), but the Tamper switch was working. There is a fault showing on Z3 when the system is powered up.

I've checked all the connections and tried the same on Z1, with the same results. I've gone back and done the pre installation tests, and all appears to be fine. I'm obviously missing something very simple.

Any offers of help would be greatly appreciated

Check make sure the fuse hasnt blown for the Aux power circuit. If you have a multimeter make sure you are getting 12v out of the Aux supply, also if you have a multimeter check the continuity of the REL circuit, it should be normally closed when inactive.

Dale