HD48… and HD49… series of transmitters measure temperature, relative humidity and the dew point temperature.Versions with only standard analog output or with only RS485 output with MODBUS‑ RTU protocol are available. The models with analog output provide a signal suitable for transmission to a remote display, recorder or PLC. The models with RS485 output are suitable for connection to a PC or PLC.The models of the HD48… series are active transmitters and accept both direct and 24Vac alternating power supply; they have standard current (4…20 mA) or voltage (0…10V) outputs, or a serial RS485 output, depending on the model. The models of the HD49… series are passive transmitters and thus suitable to be inserted in a 4…20 mA current loop.Both series of transmitters are designed for temperature and humidity control in conditioning and ventilation applications (HVAC/BEMS) in the following sectors: pharmacy, museums, clean rooms, ventilation ducts, industrial and civil sectors, crowded places, canteens, auditoria, gyms, high-density farms, greenhouses, etc.The transmitters measure relative humidity with a well proven temperature compensated capacitive sensor that assures precise and reliable measurements in the course of time. Both HD48… and HD49… series are available in two probe temperature ranges: standard -20…+80 °C and extended -40…+150 °C for the most critical applications. A stainless steel 10 μm filter protects the sensors against dust and particles (other filters are available for different applications).The transmitters are factory calibrated and no further adjustments are required.Each series is available in different versions: with horizontal probe for duct mounting (HD48…TO…, HD49… TO…) with vertical probe for wall mounting (HD48…TV…, HD49… TV…); with remote probe connected to the transmitter by means of a cable (HD48…TC…, HD49…TC…). Cable lengths available are 2, 5 and 10 m. The probes can be supplied in two different lengths: 135 mm or 335 mm. Various accessories are available for the installation: for example to fix the probe to the duct, it can be used the HD9008.31 flange, a 3/8” universal biconical connection or a PG16 metal cable gland (Ø 10…14 mm). A 4-digit optional display (“L” model) allows to display the measured parameters in a continuous or sequential mode.
