Diy temp probe

[DonW]

I'm going to take a shot at a submersible temp probe/sensor. I use little lm34's around the house for ambient sensors. Never stuck one in sw so will have to see what happens. I'm going to try acrylic and weldon on the first attempt.

Don

 

[richard55]

You could try filling a piece of heat shrink with silicon and the sensor. then heat up the heat shrink to squeeze out the silicon. Acrylic maybe to think to give a good temp reading. What type of curcuit are you using to read the value.

 

[DonW]

Here it is, a success. The acrylic is 3/8 rod drilled with a #7 bit. The fitting is just a JG clone. The pics are just a test run, it will be mounted in a bulkhead then wired to the controller. It sends linear mv so .790vdc = 79f.

Don

 

[Krish]

So Don...Once you get it all set up and submerge your little gadget, what do you do? Do you go by a regular thermometer to calibrate your unit to compensate for the acrylic? I know with like PH monitors they give you a solution to calibrate it...Is it sort of the same approach you are going to take, but by a thermometer? Your sensor looks good IMO. You are a handy dude! I hope it works out as planned...

 

[DonW]

So Don...Once you get it all set up and submerge your little gadget, what do you do? Do you go by a regular thermometer to calibrate your unit to compensate for the acrylic? I know with like PH monitors they give you a solution to calibrate it...Is it sort of the same approach you are going to take, but by a thermometer? Your sensor looks good IMO. You are a handy dude! I hope it works out as planned...

Krish there is no need to calibrate a linear ic, you only calibrate rtd and thermistors. You see the pic of the dvom .790 is 79f. The other is my chiller controller 79f as you can see it dead on through the acrylic. The controller will read the mv and respond to the temp. For example, shut down the halides if temp rises.

Don

 

[Krish]

True true...That'll work!

 

[richard55]

The Lm series give a tenth volt per degree. you can get them in centigrate also.

 

[big t]

Well Don, I am glad that this worked out for you. I am getting itchy to get a ocelot now. I think I need to sell some frags

 

[DonW]

Well Don, I am glad that this worked out for you. I am getting itchy to get a ocelot now. I think I need to sell some frags

Thanks Tom,

I'll make it smaller and more refined now that I know it works. Need to order more lm34's. I misplaced a package of 50 and can't find them any where.

Don

 

[laverda]

Do you know if this will work on a AQ3? If I go to the eletronics store do I just ask for a LM34?

 

[DonW]

I doubt it will work with a aquacontroller. This is for a digital io. You probably need a thermister. You should be able to tell by the number of wires on the controller.

Don