Things You'll Need
Intermatic Incorporated manufactures pool timers for residential use. A pool timer controls the pool pump's run time. The Intermatic pool timer uses a 24-hour dial with at least two adjustable trippers that activate the pool pump. After passing the "On" tripper, the pump motor runs until the dial passes the "Off" tripper. The pump remains off until the dial reaches the next "On" tripper. The timer's motor taps into the wires that enter the unit. An Intermatic pool timer also contains a manual lever, which bypasses the automatic trippers.
Open the circuit breaker box and turn off the circuit breaker labeled "Pool" or "Pool pump."
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Depress the latch on the side of the Intermatic pool timer's lid. Swing the lid open. This reveals the dial, manual level and the plastic cap that covers the wires.
Remove the plastic cap from the timer. Pry on the top of the cap and lift it out.
Remove the round disks from the bottom of the timer's box with a slotted screwdriver. Wedge the screwdriver's blade between a disk and the box. Pry the disk free. Repeat this with the second disk.
Push a wire clamp into each of the box's holes. Spin the wire clamp's locking nut over the clamp's threads. A wire clamp uses two slotted-screws to pinch the clamp's two halves against a wire.
Insert the wire set from the circuit breaker into the timer's housing through one of the wire clamps in the bottom of the timer. Do the same for the wire set that leads to the pool pump. Each wire set contains a wire with black insulation, a wire with white insulation and a wire without insulation.
Tighten the wire clamps' screws with the slotted screwdriver.
Remove 3/8 inch of insulation from each wire with wire strippers. Place the wire into the strippers, squeeze the handles and pull the insulation off.
Loosen the four terminal screws and the green ground screw with a slotted screwdriver. The four terminal screws, found near the bottom of the box, use numbered labels to identify them. The green ground screw, located to the left of the dial, grounds the case and protects a user from accidental electric shock. Leave the screw on the terminal with the "A" label tight.
Bend both uninsulated copper wires around the pool timer's ground screw and tighten the screw with the slotted screwdriver. Use care to route these wires away from the four electrical terminals.
Bend the white wire from the circuit breaker around the screw in terminal "1." Tighten the terminal screw with the slotted screwdriver.
Bend the white wire that leads to the pool pump around the screw in terminal "2." Tighten the screw with the slotted screwdriver.
Bend the black wire from the circuit breaker around the screw in terminal "3." Tighten the screw with a slotted screwdriver.
Bend the black wire that leads to the pool pump around the screw in terminal "4." Tighten the screw with a slotted screwdriver.
Replace the plastic cap before closing the lid and testing the pool timer.