Light Dependent Resistor in water

**mathew086** · Nov10-09, 07:22 AM

Is a Light Dependent Resistor (LDR) resistant to water? Will there be any problems if it is exposed to water directly???

**vk6kro** · Nov10-09, 07:55 AM

They look fairly well sealed but I'd worry about insulating the wires.

Could you put it in a test tube or something similar?

**mathew086** · Nov10-09, 09:50 AM

The insulating wires will not be exposed to water. Just the LDR head will be exposed to water.

If inserted inside a testube, the light intensity recieved will be further reduced , right? or no??

**vk6kro** · Nov10-09, 10:06 AM

The only CdS cells I have seen would be hard to immerse in water without getting the wires wet. They are small and quite thin.

Test tube glass would be pretty good at transmitting visible light, I think, but I haven't measured this. They look like they transmit light very well.
Easy to check if you already have a LDR.
Thin soda glass test tubes are cheap and would be worth a try.

What are you trying to do?

**mathew086** · Nov10-09, 04:07 PM

I am having a pipe. I am planning to put an array or LEDs on one side and the LDR on the opposite side ( inside the pipe). So planning to bore a small hole in the size of head of LDR and keeping just that head inside the pipe.