How to Wire a Time Switch

outdoor patio set at dusk
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  • 01 of 06

    What Is a Time Switch?

    So, what exactly is a time switch? The concept is really pretty simple. It is a device with a built-in timer that turns a circuit on and off. It simply does the work for you.

    Inside the door cover, you'll notice instructions on how to use the time switch and the rating limits for the ​time switch. This particular time switch is rated for 40 amps, 125 volts, 4375 watts, 690 VA pilot duty, and 1 HP.

    Time switches are great for indoor or outdoor lighting, small outdoor pond pumps, swimming pool pumps, and other devices that need to be turned on and off throughout the day.

    The time switch time is set by lifting up on the timer dial and turning it to the proper time. This is set by lining the time of day on the dial, with the silver time arm in the center of the dial. Caution! Do not turn the center time arm pointer! When power is applied to the time switch, the motorized dial will keep time, just like a clock or watch.

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  • 02 of 06

    Connecting the Ground Wires

    When wiring a time switch, you'll need to connect the ground wires. To do this, first twist the ground wires together, cut one off shorter than the other, bend a hook on the longer wire, and connect the ground wire to the green ground screw on the face of the time switch.

    Run the ground wires far on the side of the box, away from the terminal connections. Form them in such a way that they cannot short out against any of the connection points.

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  • 03 of 06

    Connect the Neutral Wires to a Time Switch

    The next step in wiring the time switch is to connect the neutral wires. Strip the insulation from the white neutral wires about 1/2” and connect the wires under the far left terminal screw. In this case, the terminal screw is brass.

    Place the wires under the screw clamp and tighten snugly. Form the wires neatly and tuck the excess in the bottom opening of the box. If you remember the connections when wiring an outlet, the "hot" wires connect to brass-colored terminals and the neutral wires connect to silver-colored terminals.

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  • 04 of 06

    Connect the Line Connectionto a Time Switch

    Time switches have line and load connections. Quite simply the line connection is the feed coming in from the circuit or breaker that will feed the time switch.

    Strip the black line wire's insulation about1/2” and place it under the next terminal (center terminal) available on the time switch. Tighten the wire snugly and form the wire into the bottom of the box.

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  • 05 of 06

    Connect the Load Connection to a Time Switch

    In order for the time switch to actually switch a device on and off, you'll need to connect the switch leg to the load connection. This will be the terminal on the right, the only one left in this case.

    This is the wire that actually feeds the device. Strip the black line wire's insulation about 1/2” and place it under the terminal screw. Tighten the wire snugly and form the wire into the bottom of the box.

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  • 06 of 06

    Install the Flash Shield on a Time Switch

    For safety purposes, time switches come with a wire terminal flash shield. It shields you a flash that could occur when a hot wire comes in contact with a neutral or ground wire. This would cause a short and sparks would fly. In some cases, the sparks could fly out of the box, spraying sparks into your face and eyes.

    This little piece of clear plastic may not look like much, but use it for a safe operation. It simply slides over a plastic tab that holds it in place. You'll notice that the shield has markings to show the proper wiring connections.