I have a project that turns on an LED that is built into an outdoor squirrel statue. It works great, except for the fact that the LDR that turns on the LED at night, goes bad after a couple of months. What can I do to keep it working? Or are there outdoor rated LDR's?
Does it get moist or sun burnt? Or both?
Did you try a phototransistor instead?
Did you outdoor proof the project? Did you miss something?
I have seen this posted before on this forum. Moisture rots away the LDR.
Try covering the wires at the bottom entry of the LDR in vaseline after you have replaced it.
Leo..
The LDR does not need to be "in" the sunlight to work. It can be covered and protected from rain, dew and sunlight, and still detect light. You must discover the light threshold you need.
Moisture can be very tricky because as temperature goes-down relative humidity goes-up. It can be dry and sealed but when it gets cold you get condensation. Then it's even worse if the condensation freezes.
Have you tried using liquid insulation tape?
It is a rubber like compound that cures and can form a moisture resistance coating.
See this to get you started
Liquid insulation tape
Just a word of caution. This sort of product has a limited shelf life and with some suppliers you can get tubes that have already set solid. But then you can apply for a refund or exchange.
How have you wired this ? One (bad) way, which could reduce the LDR lifetime, is to wire the LDR across the LED so it shorts out the led in daylight. Even worse would be shorting out both the LED and its series resistor (if any).
How do you know it goes bad?
When I needed an outdoor light level sensor I used:
For a housing I used an inverted glass jar with the lid bolted to a small bracket. I can't remember when I put it up but it must be getting on for 10 years and it's still working fine.
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Years ago someone gave my wife a thing to put in her flower garden. It has a small solar panel to charge a battery and has a led that turns on at night. The solar panel does double duty to charge that battery in the day and to tell the electronics to turn on the LED when the sun goes down. No LDR needed.
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Most cheap garden lights use a 4-pin control chip that uses the solar cell also as day/night detector.
Leo..
In the absense of further details from the OP, it could be something like this creation which is on sale at Amazon: Amazon.com : Resin Hanging Squirrel Garden Statue Solar LED Eye Lights Animal Yard Decoration : Tools & Home Improvement
If so, my preferred solution would be the trash can,
I had a simmilar one, which was thrown away after 1 ½ years outside.
Leo..
Well, it was my late, handicapped brother-in-law's, who died of COVID. My wife repainted it and had me fix the electronics, so the trash is NOT an option.
Well, it was my late, handicapped brother-in-law's, who died of COVID. My wife repainted it and had me fix the electronics, so the trash is NOT an option.
Garden ornaments like that use the solar panel itself as day/night detector.
They don't have an LDR at all.
The solar panels of those cheap Chinese garden ornaments rot away in less than two years. when kept outside. There is nothing you can do about bad quality.
Buy a bunch of new ones with the same solar cell, and replace when it fails.
By that time you should also replace the rechargeable battery.
Use a hair drier to soften the hot glue around the solar panel.
Leo...