Note: The waterproofing is sufficient for most situations, but is not for continued immersion.

The TandD TR-52s model with its standard external sensor can measure and record from -60°C to 155°C. With one unit you can record up to 16,000 readings. If set at a one hour recording interval that gives you 666 days or almost two years of readings. The TandD TR-51s gives you eight recording intervals (1 minute-1 hour) to choose from, while the TandD TR-52s stretches those choices to fifteen (1 second-1 hour). Each unit allows you two choices of recording method:

One time: when 16,000 readings have been reached recording stops.
Endless method: when 16,000 readings have been reached it automatically overwrites oldest data.

Using our specially designed low energy consumption circuit this unit can run on one Lithium battery for up to two years of continued use. No need to worry about where you place it, as the battery will allow you to measure and record over long periods of time whether the unit is in transit or in a distant place. 

Note: Battery life will depend on the recording environment, recording interval, communication frequency, and ambient temperature. The above battery life test was carried out using brand new batteries and in no way do we guarantee a battery's life.

With the TR-5 series any number of main units (TR-51s, TR-52s) can be used with just one Communication Port (TR-50u). Hence by simply buying the main unit you can expand your system easily and affordably.