GAI-Tronics 12579-003 Monitored Relay Module (MRM) - Manual (Page 11)

Pub. 42004-716L2C
Model 12579-003 Monitored Relay Module Page 11 of 16
f:\standard ioms - current release\42004 instr. manuals\42004-716l2c.doc
05/12
CAUTION
If ac-powered signaling devices are being used on an output loop configured for Mode 4 (Figure 9),
observe the following limitations necessary for reliable operation for the loop monitoring feature:
 The dc-resistance measured across the loop (with both end-of-line device and the MRM
removed from the loop) must be at least 100 k

 Do NOT use blocking diodes in this loop.
Figure 9. IAC Line Supervision – AC-Powered Beacons