An existing light switch is to be augmented with a parallel Sensor Switch PP20 relay, which is driven by PIR (passive infrared) sensors.

The current switch is a two terminal device and was wired into the hot side of the lighting circuit: enter image description here

The upper black leg is hot and connected to the lower black leg upon command. The wiring of the relay's terminals is well-understood. The two bare wires must be connected to the upper (hot) leg:

enter image description here

Is there a clever method / part that would allow the two bare wires to be connected to the black wire without removing the black leg from the timer switch?

Wiring is not easily taken out of the switch: Side view of incumbent timer-switch:

enter image description here


The faceplate of the timer switch was removed and revealed two screws to clamp down the existing wiring connections. Screws were loosened: stranded relay wiring was inserted follow by solid core wiring:

enter image description here

  • 1
    Seems odd that you can't disconnect the wire... connecting the wires together and running a pigtail to the switch would be the normal way to handle this. – JPhi1618 Apr 24 '19 at 19:21
  • What make and model is the relay you are using? – ThreePhaseEel Apr 24 '19 at 22:54
  • OP update to reflect a SensorSwitch PP20 relay. – gatorback Apr 24 '19 at 23:32
  • I kind of get the impression this is an old school smart switch, and it has a "safety cover" on the back that pops off to gain access to the wires. – Harper - Reinstate Monica Apr 25 '19 at 16:39
  • 1
    i would chop it at the midpoint and shove them all into a wago terminal. – dandavis Apr 25 '19 at 18:23

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