Installation guide

17
LOOP-WIRING CONFIGURATIONS
Each Model 1020 D-LEM provides for two separate zone input loops to be connected. Effective
L mid-1995, for ULC-listed installations using 2 EOL resistor loops, you may use a Form B
(SPST-NC) contact, connected in parallel with one of the two resistors. A short across the loop
will result in a tamper alarm, a break in the loop in a disconnect alarm, and operation of the
Form B contact (open across one resistor) in a general alarm. Each 2 EOL loop must have two
2,200-ohm (red-red-red) resistors in series with the loop and the normally closed alarm contacts
are connected across one of the resistors. In the case of motion sensors, etc., the tamper contacts
are connected in series with the loop.
Circuit Wiring for ULC or Non-ULC Listed Installations
The above circuit wiring is easily implemented in a standard QBB block that may be installed
close to the detector.
Connection inside an intrusion detector is even simpler: