Installation Guide
16
Figure 9-C
Figure 9-B, Interconnect Wiring Diagram
Wiring Instructions for AC Quick Connector Harness
CAUTION: Turn off the main power to the circuit before wiring the alarm.
• For alarms that are used as single station, DO NOT CONNECT THE RED WIRE TO ANYTHING. Leave
the red wire insulating cap in place to make certain that the red wire cannot contact any metal parts
or the electrical box.
• When alarms are hardwire interconnected, all interconnected units must be powered from a single
circuit.
• A maximum of 24 Kidde Safety devices may be interconnected in a multiple station arrangement.
The interconnect system should not exceed the NFPA interconnect limit of 12 smoke alarms and/or
18 alarms total (smoke, CO, Smoke/ CO Combination, heat, etc.). With 18 alarms interconnected, it is
still possible to interconnect up to a total of 6 remote signaling devices and/or relay modules.
• Figure 9-B illustrates interconnection wiring. Improper connection will result in damage to the alarm,
failure to operate, or a shock hazard.
• Make certain alarms are wired to a continuous (non-switched) power line.
NOTE: Use standard UL Listed household wire (as required by local codes) available at all electrical
supply stores and most hardware stores.
Kidde Relay Module
SM120X, CO120X
or both
Wires on alarm harness: Connected to:
Black: Hot side of AC line
White: Neutral side of AC line
Red: Interconnect lines (red wires) of other
units in the multiple station set-up
Service
Panel
Receptacles Interconnected alarms
Wiring practice that has had good results
in preventing nuisance alarms
L
N
FUSE OR CIRCUIT BREAKER
Additional
Alarm
RED
BLACK
WHITE
Additional
Alarm
RED
BLACK
WHITE
RED
BLACK
WHITE
Optional
Accessory
First
Alarm