Irrigation Rain Sensor

Irrigation rain sensor can be integrated together with a water distribution irrigation system to assist the growing of agricultural crops or maintenance of garden landscape during a period of the dry season (inadequate rainfall).

An irrigation rain sensor can be used together with a controller to determine if rainfall is adequate. When there is not enough rainfall, the controller can activate a watering system to deliver water from a water reservoir (where rainwater are collected during a raining season). Fresh water can be an alternative source of water when the rainwater reservoir runs dry.

indoor agricultural crops irrigation monitored with rain sensor


Rain Sensor compared to a Soil Moisture Sensor

rain sensor for agricultural crops water irrigation      

The precision watering of agricultural crops depends on a lot of the availability of water to the plant. The level of water content in the soil becomes critical.

A soil moisture sensor can be deployed on the ground to detect the water content on the ground. However, most of such moisture sensor works base on the principle of soil resistivity. This means that the soil condition will also have an impact on the reading of the sensor. The water content of the soil also varies on the ground depending on how the water seeps through the soil and how compact the soil are.

The moisture sensor probe has to constantly be in contact with the soil. Over a long period of use, the surface of the probe may be corroded which can affect the reading from the soil.

All these can influence the soil’s water content reading. This can mean that an array of such sensors has to be deployed across the land for a better estimate of the overall soil moisture content level.

Agricultural crops water monitoring is required, and precision on the soil moisture is quite unnecessary. Rain sensor, air humidity together with a temperature sensor has a much better monitoring efficiency compare to a moisture sensor on the ground. In most cases, you need only one set of sensors across the field and probably another set for redundancy. This is because the rain and environmental condition are uniformly distributed within the atmosphere of a geographical area.

The design of a rain sensor (detection of water presence using optical light), help keeps the water away from the electronic with a water tight clear dome enclosure. There are no mechanical parts to worry about, and it is suitable under most weather condition, making it a robust rain sensor with longer operating life span.

The rain sensor is more efficient compared to a soil moisture sensor, as it can estimate the soil condition well with fewer sensors, less energy and less cost.


Drip Irrigation

Drip irrigation irrigates the agricultural crops with water dripping directly above the crop’s root (the region around the stem or trunk). The root is where water is absorbed by the plants, and the drip irrigation method targets the delivering of water directly to the root of the agricultural crops.

drip irrigation piping along the vegetable crops dripping water irrigation delivery near to the root of the plant crops

Drip irrigation using together with a rain sensor can typically be seen in Malaysia agricultural land, a tropical country in South East Asia.


  • Saves water
  • Saves fertilizer
  • Less soil erosion
  • Uniform water distribution
  • Less weed growth
  • Save energy, less pressure to operate

water dripping irrigation pipe outlet system drip irrigation pipe across the outdoor farm field


Sprinkler System

Sprinkler system irrigation is more appealing for beautifying landscape compared to the drip irrigation. Unlike the drip irrigation, the pipes are usually laid below the ground. The piping is hidden from view, and there is no pipe blocking the walking path. The sprinkler system is suitable for garden, landscape, grass patch water irrigation. The sprinkled water can also help to cool down any warm and dry outdoor environment.

Such a water sprinkler system can be used together with a rain sensor to provide garden watering to a designer landscape. Such rain sensing system can be seen in a garden city like Singapore. Check out the water sprinkler for gardening automation using rain sensor in Singapore.


  • Hidden piping under the soil
  • Single point sprinkler location
  • Visually see irrigation taking place
  • Cool down the surrounding


Rain Sensor and Controller System

Check out the recommended RG-11 rain sensor from our sensor selection page, or buy your rain sensor from our online purchase page.

For Ethernet, USB or other communication connectivity I/O controller, please check out our standard Ethernet I/O controller and USB I/O controller products.