HVAC40… series transmitters and hygrostats measure temperature, relative humidity and dew point using an interchangeable relative humidity and temperature digital sensor. A stainless steel 10 µm filter protects the sensor against dust and particles (other filters are available for different applications).
The probe is available in three different versions:
Fixed vertical probe for wall mounting (HVAC40...TV);
Fixed probe with 2 m cable (HVAC40...TC.2);
Fixed duct horizontal probe (HVAC40...TO).
Available outputs, depending on the model:
RS485 Modbus–RTU digital output (HVAC40S17…);
0...10 V voltage analog output (HVAC40V17…);
0...20 mA / 4...20 mA active current analog output (HVAC4017…);
2-wire (current loop) 4...20 mA analog output (HVAC40A17…);
ON/OFF relay switch (HVAC40R17…).
Versions with 4-digit LCD display (option L) are available, which allow the measured parameters to be displayed. In the versions with LCD, two LED indicators indicate the presence of the power supply and of an eventual alarm condition: exceeding of the set measurements thresholds, in the versions with relay switch output; measurement detected outside the measuring range, in the versions with analog or digital output. The instruments are factory calibrated and ready for use. The configuration can be made by connecting the serial port of the instrument to the PC or by means of the quick configuration dip switches on the circuit board. The versions with relay switch output are equipped with two internal buttons for the configuration via display.
RH: analog outputs are corresponding to a full scale of 0 to 100 %; Temperature: analog ouputs are user configurable, standard version -20…+80 °C.
Alarm: Front red LED - measurement detected outside the measuring range (except relay versions); For relay versions - front red LED + internal buzzer for exceeding of the set measurement thresold
Power Supply: Active analog out.: 24 Vac ± 10% or 18…40 Vdc; Current loop: 15…30 Vdc; Modbus-RTU: 12…30 Vdc; Relay: 24 Vac ± 10% or 15…36 Vdc.
Power Consumption: Active current: 20 mA @ 24 Vdc and Iout=12 mA; Voltage: 4 mA @ 24 Vdc; Modbus-RTU: 2 mA @ 24 Vdc; Relay: < 1 W @ 24 Vdc
Connection to PC: RS232 serial port - it can be connected to a USB port by using cable CP27 (except Modbus versions); Modbus versions: RS485 serial port - it can be connected to a USB port by using RS48 adapter
Sensor operating conditions: -20…+80 °C *. The sensor is protected from water and dust
Storage temperature: -20…+80 °C
Dimensions: 80 x 84 x 44 mm (housing)
Protection degree : IP65
*best performance between 20…80 % RH humidity range. Long term exposure outside this range, especially at high humidity, may temporarily offset the sensor response
(1) Delta Ohm HVAC40 Temperature, Relative Humidity and Dew Point Transmitters