Make a Waterproof Temperature Probe
Make A Waterproof Temperature Probe
Find out how to make a waterproof temperature probe
electronics | heating | waterWe include a pair of
LM335Z temperature sensors with our
solar water heating pump controllers. They are reliable, relatively inexpensive, and very easy to use, however they do have one disadvantage - they are not at all
waterproof. One sensor has to be fitted to the side of the hot water tank under the insulation - typically a nice dry area - but it can sometimes be difficult to fit the second sensor to the outlet pipe from the
solar water heating panel as this is installed outside. In some situations (such as
heating swimming pools) the temperature sensor must be submerged. Therefore in this article we will look at how a standard temperature sensor can be turned into fully waterproof temperature probe.
Making a
waterproof temperature probe is actually quite simple, requires few tools, and the component parts required are inexpensive. In short the temperature sensor must be
soldered to insulated leads, and the soldered joints protected with
heat shrink tubing (to prevent short circuits). The sensor is then inserted into a suitably sized
stainless steel tube or around 50mm length (6mm inside diameter for LM335Z sensors), and filled up with
epoxy potting compound. The potting compound is impervious to water, the stainless steel tube, will not corrode, and the steel-epoxy combination will transfer heat to the temperature quickly enough for pretty much all
solar applications. The leads sticking out of the epoxy at one end of the tube can then be connected up as required.
Buy Stainless Steel Tubing and Potting Compound
Stainless steel tube is not a very easy thing to find, but fortunately there are many sellers on
eBay UK who have it on sale. Click here to search for the latest listings for
Stainless Steel Tube. Similarly, click here for
Potting Compound, and here for
Heat Shrink Tubing.
Recommended Reading
DIY Submersible Temperature Probe - from Home Brew Talk website.
Article Last Modified: 15:37, 1st Jun 2009Comment on this Article
If you have any comments on this article, please email them to
neil@reuk.co.uk.
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