Wireless M-Bus (OMS) Temperature & Humidity Sensor

WTRH-03, from GREATEch (Germany) is a universal and wireless battery operated standalone temperature and humidity sensor utilizing the existing Smart Metering infrastructure like Multi Utility Communication devices (MUC) as standard gateways to Ethernet, DSL, GPRS and Powerline networks.

WTRH-03 is using a wireless protocol which is 100% compliant to the wireless M-Bus Open Metering Specification (OMS). The device type (DEV) is specified as Room Sensor (1BH) with send & no reply (C-Field 44H). The data format of the temperature value is a signed 16bit integer with LSB – MSB format and resolution of 0.1°C (VIF 66H). The data format of the relative humidity value is a 8bit integer and resolution of 1% (VIF FBH and VIFE 1BH extension). The Data-Field contains an access number counter (0-255) and status byte for low battery. Each sensor gets a unique serial number (4 Byte) and the transmission cycle time is user selectable.

Due to the extremely low quiescent current the battery lifetime will be greater than 10 years.

WTRH-03 is fully compatible to the wireless Ethernet Gateway WIZENET-400 Made by GREATech.