Humidity transmitters for building automation systems that use Modbus serial communication protocol
RHT-MOD relative humidity transmitters are engineered for building automation systems in the HVAC/R industry. The RHT measures relative humidity (rH), and temperature (T). RHT devices are available with large touchscreen display making configuration of the device quick and easy. Configuration is also possible via Modbus network.
RHT-MOD devices include:
• Modbus communication for each measurement parameter (rH and T)
• One analog output for selected measurement: voltage (0/2–10 V) and current (4–20 mA)
• Optional relay output
Technical details
Communication:
RS-485 Modbus (RTU)
Accurary:
Temperature: <0.5 °C
Relative humidity: ±2…3 % rH at 0…50 °C and 10…90 % rH
Total error band includes accuracy, hysteresis and temperature effect over 5...50 °C and 10–90 % rH
Measuring units:
°C, % rH
Measurement elements:
Pt1000 temperature sensor, thermoset polymer capacitive sensing element for humidity
Supply voltage:
24 VDC/VAC ±10 %
Current consumption:
max 90 mA (at 24 V) + 10 mA for each voltage output or 20 mA for each current output
Output signal for selected measurement:
0/2…10 V (linear to rH or T), L min 1 kΩ or
4…20 mA (linear to rH or T), L max 500 Ω
Optional relay output:
Potential free SPDT 250 VAC, 6 A / 30 VDC, 6 A with adjustable switching point and hysteresis
