The HD9008TRR and HD9009TRR are single block RH and temperature microprocessor
transmitters, temperature confi gurable. The HD9008TRR is a passive transmitter with a
4…20mA output and 10…30Vdc power supply; the HD9009TRR is a transmitter with a
0…1V standard voltage output (other outputs available on demand) and 5…35Vdc power
supply. Sensors are mounted at the end of a plastic tube: a capacitive humidity sensor
and a Platinum temperature sensor (100Ω @0°C).
The instrument can be reprogrammed by means of a key, and no jumper or potentiometer
actions are required. The humidity input can be recalibrated by using two saturated solutions: the first one at 75%, the second one at 3