Automatic Sprinkler

Automatic sprinkler system controllers are programmed to operate or go off on certain days and at fixed time. The controller can not sense the weather conditions, and for the same reason every lawn sprinkler requires a rain sensor.

Rain sensor determines whether sufficient rainfall has occurred and whether or not to skip an irrigation cycle. Rain sensors are of three basic types, all serving the same purpose- preventing your system from over watering your garden. There is some sort of electrical connection between the sprinkler and the sensor which gets interrupted when a certain amount of rain triggers the device. The sensor breaks the electrical connection so as to stop the flow of electricity to either the sprinkler valves or to a pump start.

One of the type works by measuring the water collected in the rainfall collection cup. However there are certain problems involved with this type; the leaves, sticks or insects might fall into the collection cup, leading to a turn off.

The next type uses electrodes to measure the amount of water in the collection cup. This type of rain sensor device also involves the same problem of things, other than rain water, collecting in the collection cup.

Most common amongst such rain sensors is the expansion disk device. This type is usually used by professionals. This system does not use a collection cup, but instead it has cork discs which tend to expand due to rainfall, and the pressure switch which is used, breaks the electrical connection. One can adjust this in increments of ¼ inch to the desired rain fall setting. Usually, this adjustment is set to turn the sprinklers off after ½ inch of rain has already fallen.

The most important aspect of installation is where to place it. It chosen area should be unobstructed by trees, roof over hangs, or anything else that might block rain from getting to the sensor. In case of a wired sensor, placement is generally near the sprinkler controller. One should connect the wires inside the controller’s valve wiring panel so as to allow easier electrical trouble-shooting of the system as the sensor can be easily disconnected.

FM wireless rain sensors are also very popular. They are certainly more expensive than the wired devices, but the ease of installation and increased placement options make them more preferable. Most of them come with a built in by-pass switch. Certain digital controllers may also offer by-pass options for both wireless and wired devises.

Irrespective of the type of sensor, it always offers innumerable advantages over not having one.

·   Saves money whether you pay for city water or use an electric pump.

·   Increases the life span of your sprinkler system.

·   Preserves water resources by limiting the use.

The amount of money you save by installing a rain sensor certainly depends on your water source and where you live- water source, climate, electricity rates, etc, but however having one is always a decent choice.