Fridge Temperature controller

[Garak]

I use a an as35 or lm35 linear temperature sensor. Looks just like a transistor. They output degrees centigrade in 10mV increments. So 10mV output is 1 degree celsius. Super easy to use, I picked up the ones I'm using for like 50cents each. The only problem I've been having is that long cables can throw in some error. There are a few circuits in the datasheet to correct for this and allow for negative readings but I'd rather keep it simple.

I'm thinking I'm going to switch to digital sensors. Same package with a digital "1 wire" output. Takes all the error out of it.

The next step is to seal them into a piece of copper or stainless tubing. Anyone know of something that is conductive to heat but not electricity to pack in around the sensor. I've used epoxy in the past but it acts as a bit of an insulator, slowing down readings.

I want to make up some bungs with a hole for a stainless probe and one for an airlock for monitoring fermentation temperature.

[mr x]

I can't imagine anything that you would pack around the sensor that wouldn't slow down the reading. If you need some ss tubing, let me know.

[Garak]

Well epoxy is better than air but there must be something better than that. I wounder would heatsink compound do the trick? Is that stuff electrically conductive I wonder?

Any ideas on how to seal the end of a stainless tube that wouldn't leave anywhere for any beer spoilers to hide?

[akr71]

I have a spare flask over here in Hfx. And a stir bar IIRC.

How much do you want for them?

[mr x]

For sealing the end of the probe, I think a little bit of epoxy is OK, or maybe some food grade silicone sealant. Then boil the probe end before inserting into sensitive wort.

I don't want anything for them, but the flask is only 1 litre.

[akr71]

If Garak is willing to put together a stir plate (sorry, not trying to hijak the thread) for me or anyone else, I'd much prefer him to have the stir bar & flask.

[ratchet]

Well epoxy is better than air but there must be something better than that. I wounder would heatsink compound do the trick? Is that stuff electrically conductive I wonder?

Any ideas on how to seal the end of a stainless tube that wouldn't leave anywhere for any beer spoilers to hide?

weld it.