TV2 chart of 2 temps

Logging temperature

Data loggers: One way to monitor a freezer or cooler’s temperature

Data loggers are devices that can be used to sample and store temperature and/or humidity at regular intervals. Before data loggers, chart recorders used paper charts to record the information. This was useful but the amount of data they could display was limited and if the user forgot to change the chart mostly useless. The modern data logger stores the temperature history in its computer memory until it can be downloaded to a computer.

Data loggers were originally designed as weather forecasting tools, but were quickly adopted as a much better way to monitor freezers and refrigerators. Keeping stable temperature in a freezer is much more important than most people think. It is especially true when deep frozen food is stored where ten degrees can make the difference between safely stored food and food which can promote bacteria growth. The 10-degree difference in temperature might seem small, but it is crucial for deep frozen products.

Data loggers are absolutely necessary in professional freezers. The standard thermometer inside the freezer shows only the present temperature. Data loggers records temperature fluctuations all the time even when no one is looking.

There is at least one problem with data loggers that limits their usefulness. Although they record temperature history they do not display the temperature history. They must be downloaded to a computer before the history can be viewed.

Fortunately there has been an improvement to the data logger that overcomes this problem:  The TV2,
The Master Thermometer

Unlike other data loggers, The Master Thermometer works all by itself. It has a processor, its own memory and a big LCD screen, it doesn’t need a computer or any other device to display all the data it has stored in memory. Its sensors can be placed up to 300 feet from the display unit, which allows it to monitor and document temperature even in large freezers. As everything is stored in the Master Thermometer’s non volatile internal memory and is displayed on the LCD screen. A temperature chart is drawn on the LCD display so that anyone can immediately tell what has occurred within the last day, week or even month.

For more information please visit Two Dimensional Instruments:

Information About The Author

Rick Kaestner is the President and CEO of Two Dimensional Instruments; the worldwide leader
in providing technology to monitor, chart, alarm and record temperature and humidity. For
more information please visit their website at