HD 9408T BARO, HD 9408TR BARO and HD 9908T BARO are analog output
electronic barometers. They use a piezoresistive sensor element which gives
extremely accurate and stable measurement of the atmospheric pressure and
assures excellent repeatability, low hysteresis and very good temperature stability.
The output signal of the sensor is conditioned to provide a voltage or a
current output linearly proportional to the barometric pressure. The transmitters
are ready as they have been calibrated at the factory. A zero adjustments potentiometer
is available for offset to station elevation.
HD9408T BARO requires a continuous dc power supply, its low power consumption
(< 4 mA) makes it ideal for portable and remote battery or solar
powered applications. It is available in different kinds of analog output:
0-1 Vdc, 0-5 Vdc (1-5 Vdc, 1-6 Vdc on request) or 4-20 mA (two wires).
HD 9408TR BARO offers superior temperature performance: the internal circuitry
allows the sensor to work at constant temperature so that it achieves accurate
temperature compensation over the whole range from -40°C to +60°C.
HD 9408TR BARO requires a continuous dc power supply and a differential
cabling connection to achieve best results. It is available in different output versions:
0÷1 Vdc, 0÷5 Vdc (1÷5 Vdc, 1÷6 Vdc on request).
HD 9908T BARO, unlike the other models, is equipped with a display showing the
pressure measurements, an analog output 0÷20 mA, 4÷20 mA, 0÷1 V and 0÷5 V
(0÷10 V on request) configurable by the customer and with an ON/OFF relay output
with programmable alarm threshold.
HD 9908T BARO requires a 24 Vac (or 220 Vac on request) power supply.
HD 9408T BARO, HD 9408TR BARO and HD 9908T BARO are low cost and
excellent performance solutions for meteorological applications, environmental
monitoring systems, metrological and environmental data logging, altitude
applications, barometric pressure compensation in the performance of internal
combustion engine, cleanroom barometric pressure compensation, testing of
vehicle emissions.
HOUSING AND INSTALLATION
In all models the sensor electronics are housed in a sturdy MACROLON with
IP67 protection. Opening the lid holes are available that allow you to secure the
base of the transmitter directly to a panel or a wall. The measurement accuracy
is independent of the position of the transmitter. However, it is advisable
to mount the transmitter so that the sensor is facing down to reduce dust and
dirt on the filter. If the installation is in an open environment is recommended
to use a special static port to minimize errors caused by the wind flow on the
input pressure.
