Do you have any cheaper and lower power consuption rain detector?
What model do you have?
We now use Vaisala's.Because hard competition with Vaisala, our price is not so good. Another big problem is that the power consuption is too big.
I see CSL had such a product now, but, they haven't responsed to me upon my enquiry.
We are developing a road weather station, we like to use such a sensor in remote site.
Most rain detectors on cars often rely on the screen wipers to clean off moisture so the sensor can quickly detect the end of a rain event.
If you are not bothered about the prompt detection of when it stops raining you could use such a sensor or the Campbell Scientific 237 or the new LWS leaf wetness sensors, which are relatively cheap, can detect the onset of rain quickly, and are low power. The end of an event relies on water evaporating or running off the sensor. Being unheated the sensors won't work in well in freezing conditions.
If you want fast response and deicing then the sensor CSL are offering might be an option. This is the manufacturers link.
http://www.deltaohm.com/ver05_06/analisi-rilevpioggia.php?lingua=uk
There are other technologies you can look at, see:
http://www.thiesclima.com/precipitation_monitor.htm
But none of these are "cheap" or particularly low power.