logo tagline








EtherRain Logo

Home > Products > EtherRain >EtherRain Rain Sensors

Durable Rain Sensor for EtherRain

EtherRain Sprinkler Controller Rain Sensor Top/Bottom Image

EtherRain has a a rain sensor port that works with any commerically available "normally open" rain sensor. You may not need a rain sensor if you are using one of our schedulers (OptiRain or LanwnCheck) and have selected a reliable and full function weather station from the WeatherUnderground network. But if you want to be 100% certian that your irrigation does not operate while you are experiencing a wet environment, then you should use a rain sensor. If you don't already have a rain sensor for your controller and are using EtherRain, consider the EtherRain Rain Sensor.

The EtherRain Rain Sensor is an economical and durable sensor capable of detecting precipitation when attached to the Rain Sensor input of an EtherRain Controller. The sensor includes an eight inch long bendable aluminum mounting bracket to provide flexible mounting alternatives.

The EtherRain Rain Sensor was designed to last a long time. It features an industrial wool felt wick that absorbs water. This hydroscopic material holds water and keeps the rain detection signal active for a length of time beyond the end of the precipitation event. The printed board-based sensor utilized FR-4 expoxy glass substrate and has a heavy coating of tin solder (lead free) and is resistant to corrosion in rain sensing applications. Once the rain detection signal is activated the signal remains active until the wick is dryed out. The drying period depends on surrounding environmental conditions and can take from 1 to 48 hours.

Durability Update - 2009 through 2020 - 11 years and Counting:
Our main test sensor has been in continuous operation for over eleven years. It is located in a southern facing position that faces a gruelling, inhospitable California sun in San Jose, CA. With no cloud shield, the California sky provides sunlight that is rich the type of ultraviolet radition (UVA/UVB) that quickly destroys plastic (along with my car's finish!). Our test sensor works flawlessly reporting rain reliably and is in excellent condition with no material degradation.

Download and view the EtherRain Rain Sensor Installation Guide(.pdf)




The EtherRain Rain Sensor was designed for use with the EtherRain controller family. Use of this sensor ensures that irrigation will be blocked in the event of local rain conditions. This sensor will not provide rain sensing functions for controllers other than EtherRain. It is better to mount a rain sensor closer to the ground to reduce wire weather exposure and to make installation easier.

EtherRain Rain Sensor Products List
Name Description Part # Status Price
Rain Sensor Rain Sensor, Mounting Bracket ER-RD-NW Available $8.95
Rain Sensor Rain Sensor, 25 ft Wire, Mounting Bracket ER-RD-25 Available $14.95
Rain Sensor Rain Sensor, 40 ft Wire, Mounting Bracket ER-RD-40 Available $19.95

Back to the EtherRain Product Page

Back to the EtherRain Purchase Page

Rain Detector Frequently Asked Questions

This rain detector looks too small. How could it possibly work?

Our rain detectors have been field trial tested for 8 years in Northern California, and have been in use in locations around the world for the last 7 years. When it rains, even in a light drizzle, they get wet, like most other weather exposed objects, and the sensor converts the wet condition to a signal used by the EtherRain controller.

How durable can this sensor be, it seems like it would quickly wear out?

Our rain detector is manufactured using alumimum, industrial quality wool felt, and epoxy glass board. Our felt material is the same type as that used within internal combustion engines for oil wicking. It is impervious to heat and UV light. It is hard wearing, we actually drill it and sand it. It soaks up water to hold the rain sensor signal a period of time after precipitation has stopped. Our original test sensors have been exposed to heat and UV sunlight in San Jose for over eight years running and are working as new. The materials we use will outperform the plastic and cork constructed sensors that degrade in sunlight and in freezing conditions.

Can this sensor be used with other sprinkler controllers?

No. While you can use other commerically available normally open rain sensors with EtherRain, our rain sensor was designed for use only with EtherRain. EtherRain has a special extremely low current circuit that detects when the sensor is wet. Most sprinkler controller manufacturers run much higher currents through their rain sensors and require a high current switch within the rain sensor along with much heavier control wire.

Can I use this rain detector and EtherRain simply as a remote rain detector?

It's possible, but you'd have to write your own alerting software.

Where is this rain sensor made? Can I buy it somewhere else?

We manufacture this rain sensor; it is made in the USA; (as is the EtherRain controller).

Can this sensor be shared between multiple controllers so that I only need one sensor??

Yes. We offer the ER-CK-02 and ER-CK-03 Connect/Share kits that allow a single rain sensor to be easily shared. If you are using OptiRain Open scheduling software you can assign multiple controllers to a rain sensor group which allows the sharing of a sensor between controllers without any additional wiring.