Another temperature logging product

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Oct 20, 2008
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I haven't seen a mention of the Dallas Semi (Maxim) Thermochron in any of the threads about temperature monitoring so I thought I'd pass along this info. First the obligatory: I have no association with the manufacturer or any resellers, I just think it's a cool product.

The Thermochron is small device that looks like a button battery. Inside are a realtime clock, thermometer, battery, and some circuitry. The device operates standalone, you can just set it in your cellar, or tape it to the side of a fermenter. No computer or wires are needed during logging. The device simply records its temperature every so many minutes. To view the log you need a computer with a 1-wire adapter. Free software is available to produce time vs temperature plots, highs and lows, etc. A Thermochron costs about $25, the adapter is another $20 or so. It is based on the same 1-wire technology others are using for a network of temperature sensors, except this version is not designed for process control, it's strength is telling you your temperature history.

I bought a promotional kit when the product first came out years ago and have been using it ever since. I don't like the idea of keeping a computer running just to log temps. At the end of a two week fermentation cycle I dump the temperature plots to my (virtual) brewer's notebook.

Here are the manufacturer links. A web search for "thermochron" or "DS1921" will turn up resellers and all sorts of interesting projects people have built.

QuickView - DS1921G Thermochron iButton