Zeta NPAD Installation Manual

Also see for NPAD: User manual, maintenance guide & log book

Zeta NPAD Installation Manual Manual pdf 22 page image

PREMIER AD INSTALLATION MANUAL. Software:31/3/04 & LC6Approved Document No: GLT.MAN-105 PAGE 22Issue : 1.02 Authorised: GH Date: 15/03/200411.9 LOOP WIRING FAULTSA loop fault can be caused by a break, or short circuit in theLoop wiring. Open the panel and look for the 4 green LEDs onthe termination PCB. Under normal conditions these should beall lit steady. The LEDs represent Loop1 Side A, Loop 1 side B,Loop2 Side A and Loop 2 side B.If both loop LEDs for either loop are off, then this indicates that there is a short on the loop that theisolators couldn’t bypass. (Check that the isolators are enabled, and aren’t set for a cable continuitycheck). Split the loop half way, and check if either side of the loop will power up. Continue makingmore splits until the short has been found.If The LEDs for a loop are flashing (both on, side a only, both on, side b only etc), then this indicateda break in the wiring. This could be caused by either a break, or a pair of isolators shutting down ashort circuit. If there are several missing devices (wait for the zone fault LED & check the addressesin that zone), then there is probably a short circuit on the loop (look for isolators lit Yellow or flashing).The missing devices should give an indication of the section with the break. Investigate that sectionas per the dead short circuit fault tracking method, as described above.If there are no missing devices, then there is probably a simple break. Disconnect one side of theloop and check which devices can be read. The break should be after the last read device.*** FAULT ***Loop Fault Exists