temperature sensors

dwalt

Active Member
I've been stockpiling parts to support my HAI clients. The one thing I'm running short of is temperature sensors.
I use them in an outdoor snow melt system and after 10-20 years outside they are failing. Lots of corrosion on the whole circuit board.
Looks like I'm going to have to start repairing my bad ones. Does anyone have any dead sensors I could buy? I don't care if they are standard or extended range or with Humidity. just need some spare parts. A number of components on the temp sensor board are not available anymore.
Thanks,
dwalt
 
This one might be worth creating a redesign for. They are quite simple. They do nothing more than to take a temperature range (regular or extended) and convert that to a 0-5v signal. The circuit runs on 12v. I'll search, but there has to be other circuits out there that do that. A micro-controller at the most, but probably even simplier. I'll look.
 
I started going thru my broken temp sensors. The corrosion comes off easily with vinegar and water rinse.
I need to replace some caps (mechanical damage). I believe they are Nichicon 100uf 25 volt smd caps.
The only other code on the cap looks to be G3P, G4P, PTP and a 0 with a slash thru it then 2P. All caps are the same physical size.
All the caps on the Nichicon site start with U. I could use some advice on what a proper replacement would be.
 
some pics of the caps
 

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Not much help...

Thinking user @tigers was trying to build one a while back..

 
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I can't speak for ELK, but the HAI one is very simple, the sensor outputs a voltage relative to the temp or humidity. The "extended" temp sensor does the same with a wider temp range. I think it will be hard to find off-the shelf parts to replicate this, because if the temp range of the sensor is different, the temp will read wrong. ELK may be similar, or may send a digital signal, I don't know.

Now the solution, should not be too difficult. An ESP32 should be programable for this simple function.
 
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