Orbit is a major manufacturer of irrigation products, including timers. Orbit makes a variety of 4-station timers. These timers send an electric signal to the valves in the sprinkler manifold, which control the flow of water. All of the Orbit 4-station timers run up to four individual sprinkler zones, one at a time. Although the models of timers differ, the installation procedure is generally the same whether you choose a digital timer or an analog one.
Locate an area along an interior or exterior wall where you want to install the station timer. You should make this location within 10 feet of an AC outlet. You can mount the timer in a pantry, crawl space or basement, for example.
Anchor the timer to the wall using the four screws provided in the timer kit.
Lay out the sprinkler wiring bundle from the timer to the irrigation controller outside. You may have to drill a hole through the wall to get the wiring outside. You can plug the hole later with silicone if this is needed. Some homes have built-in electrical tubing that runs from the basement to the outside.
Press the white wire into the slot marked "common" or "ground." This will be the ground source for all the sprinkler valves outside.
Press each colored wire into one of the numbered slots on the timer. If you press the red wire into the first connection, that will make the red wire control zone 1. Continue attaching wires at the control until all four zones are attached.
Go outside to the irrigation control box.
Twist the negative wires from each of the four sprinkler valve connections to the white wire. This will give all the valves a common ground. You can identify the negative wires on the valves by a stripe or solid line on the wire.
Twist one colored wire from the sprinkler wire bundle onto each of the positive wires on the valves. If you attached the red wire to zone 1 at the timer, then whatever valve you attach the red wire to will become zone 1. Continue connecting colored wires with valve wires until all four zones are attached.
Press each pair of twisted wires into a grease cap. This will seal the connection and prevent water from shorting out the timer or valves.
Plug in the sprinkler timer, and turn the dial to the "test" position. This will run each zone for a few minutes, allowing you to check the function of the timer.