The module regularly measures the temperature using a PT1000 probe in 2-wire technology. The time stamped values are transmitted to receivers of the GesySense wireless sensor network from where they are available to further processing. The logger generates a 15-minute value which is stored on the module in a memory with a capacity sufficient for one year. Even at a battery failure the values will be preserved. Along with this operation mode measured values can be radio transmitted as well immediately. Correct operation of the module is indicated by a LED. Parameterization of the logger module as well as reading out the data is done via radio using the GesySense Configurator. The wireless module is powered by a 3.6 V AA battery. Running at a sensible measurement cycle of 5 minutes the replaceable battery will operate a minimum of 5 years up to and possibly exceeding a 10 years life expectancy depending on circumstances. Generally the module is prepared for PT1000 probes measurements in the range from -99 °C to + 391 °C. Within the operating range of -40 °C â€“ +40 °C measurement accuracy is compliant with the requirements of regulation EC 37/2005 on the monitoring of temperatures in the means of warehousing and storage of quick-frozen foodstuffs.