Hunter Normally Open Mini-Clik Rain Sensor

Normally Open rain sensors must be used with controllers that have a normally open sensor terminal. You can determine if your controller is normally open by looking at the sensor terminal inside the controller and checking to see if there is a jumper wire between the terminal. A jumper wire will indicate that the controller is Normally Closed. No jumper wire will indicate the controller is Normally Open.

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This rain sensor has three blue wires coming out of it. Two are connected to a 25 foot extension, and the third blue wire is the “normally open” lead of the switch and is used in open circuit installations. The remaining two extension wires are colored (one black, the other red).