TheSkySearchers

Objective: a rain sensor that will not trigger on dew.

I have looked at the Kemo M152 rain sensor, but its heater only comes on after it has made a detection, which is too late. The Hydreon RG-11 will do the job, but I'm looking at $150 by the time I include shipping, exchange rate and tax. A bit pricey, considering that my existing sensor is reliable, just a bit over-sensitive.

So I am thinking of adding heat to my existing wet-leaf sensor using a bunch of resistors. I would run it off the 12v dome movement power supply. The heat would be on any time the dome is powered up. I am not planning to use a PWM controller.

So questions:
- How much heat is suitable for a sensor that is about 3cm by 5cm? 1W? 2W?
- If I drown the resistors in Liquid Electrical Tape, will that provide enough waterproofing, considering that it will be out in the weather?
- Any mounting tips? Any tips at all?

It wont take much. But I don't know the size of your sensor.

About the water proofing. I would not worry too much about it since it's 12 volts and not likely to cause any real issues. Still it would be good to protect it from the elements especially any direct sun.

Can you show us what sensor your using now?

UlteriorModem wrote: ↑Sat Dec 26, 2020 7:54 pm But I don't know the size of your sensor.
...
Can you show us what sensor your using now?

It looks like this. About 3cm by 5cm.

Everything you need to know here...

https://www.dewbuster.com/heater-resistors.html

I'm thinking like 3 or 4 resistors?

UlteriorModem wrote: ↑Sun Dec 27, 2020 2:18 am Everything you need to know here...

https://www.dewbuster.com/heater-resistors.html

I'm thinking like 3 or 4 resistors?

A very useful page. Thank you.

If you need any materials I have a bag full of 330 ohm resistors and the silvered wire. Just let me know.

I decided to go with the RG-11 rain sensor. It's only money. I might add heat to my existing sensor as a backup.

Let us know how it works out.