HD48.. and HD49.. series of transmitters measure temperature, relative humidity and dew
point. 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…20mA) or voltage (0…10V) outputs,
or a serial RS485 output, depending on the model. The models of the HD49.. series are passive
transmitters instead, and thus suitable to be inserted in a 4…20mA current loop.
The HD48.. and HD49.. 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 HD48.. and HD49.. transmitters measure relative humidity with a well proven temperature
compensated capacitive sensor that assures precise and reliable measurements in the
course of time. The transmitters of the 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 20μm 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 three different versions: with horizontal probe for duct mounting
(HD48...TO..., HD49…TO…), with vertical probe for wall mounting (HD48...TV..., HD49…
TV…) or with remote probe connected to the transmitter by means of a cable (HD48...TC...,
HD49…TC…), cable lengths available are 2, 5 and 10m.
The probes can be supplied in two different lengths (135mm or 335mm).
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 (∅10…14mm). A 4-digit optional LCD (“L” model) allows to display the measured
parameters in a continuous or sequential mode.
