Smoke alarms can be installed either singularly or in an interconnected pattern. The interconnected pattern is better. It’s a bit more complicated, but has the advantage of sounding all the alarms in a home should one of the alarms detect smoke. Interconnected units should be wired to the same fuse or circuit breaker. The manufacturer will recommend a maximum total length of wire (see the instruction book) and a maximum total number of alarms that can be interconnected.
Connect the white wire on the power connector to the neutral wire in the junction box for both interconnected and stand-alone alarms.
Connect the black wire on the power connector to the hot wire in the junction box for both interconnected and stand-alone alarms.
Connect the orange wire on the power connector to the interconnect wire in the junction box for interconnected alarms. Repeat for each unit. Do not connect the orange wire to a hot or neutral wire. Ignore the orange wire if you are connecting a stand-alone alarm—just tuck it away.
Don’t connect interconnected wire smoke alarms across multiple dwellings—if a false alarm were to go off, all the households would experience the unwanted alarm.
Don’t cross hot and neutral wires between alarms.