Firmware Version 4.8.52 Release Notes 

Affected ModelsZeus and Iris platforms. 

Affected Serial Numbers: All 

Firmware Version: 4.8.52 

Release Date: April 9, 2021 

Overview of changes: 

Firmware 4.8.52 adds a high-resolution temperature reporting function to Iris and Zeus platform devices with I/O Board version 9A and newer, that are using the current temperature probe(s) from Terso. This new function provides the user with more precise temperature data and temperature alarm settings. When the new ‘TemperatureHiRes’ parameter is enabled, the device will report temperatures to the tenth of a degree. Temperature limits and offsets can also be set to the tenth of a degree. 

The device is always taking temperature readings to a tenth of a degree.  The device will still report temperature as a whole or to the tenth depending on the TemperatureHiRes parameter setting. 

Along with this change, Terso is simplifying the device definitions for this firmware version and future versions.  There will only be one device definition per device type.  Device types are ambient cabinets, standard refrigerators, standard freezers, and ULT freezers.  The device definition descriptions are listed below in the New features / additions section. 


  • Firmware only reads temperature in High Resolution to a tenth of a degree Celsius.  All alarm settings use High Resolution Temperature reading, even if TemperatureHiRes is set to false, adding the benefit of better temperature alarm sensitivity. 
  • TemperatureHiRes parameter reports temperature to tenth decimal spot when set to “true”  
  • Temperature event is only generated after sensor temperature is outside an alarm parameter for greater than 10 seconds  
  • Temperature limits and offsets accept a decimal point  
  • ValidPass log entry events are now generated with every valid pass 
  • New high resolution temperature tables are included in the firmware release. 
  • New device definitions (list) 
    • FW v4.08.052, Ambient Cabinet 
    • FW v4.08.052, Standard Freezer 
    • FW v4.08.052, Standard Refrigerator 
    • FW v4.08.052, ULT 
  • Sensor offsets are settable in the Web Interface