D C B A GND VRH Vt Vdc Fig. 1 Fig. 2 Fig. 3 TEMPERATURE AND HUMIDITY TRANSMITTERS, MULTIPLATE RADIATION SHIELD HD9008TR - HD9009TR RH AND TEMPERATURE TRANSMITTERS CHARACTERISTICS The HD9008TR and HD9009TR are single block RH and temperature microprocessor transmitters, temperature confi gurable. The HD9008TR is a passive transmitter with a 4…20mA output and 7…30Vdc power supply; the HD9009TR is a transmitter with a 0…1V standard voltage output (other outputs available on demand) and 7…30Vdc power supply. Sensors are mounted at the end of a plastic tube: a capacitive humidity sensor and a Platinum...

Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Humidity Sensor Calibration The following accessories are needed. HD9008TR model: a 7…30Vdc continuous voltage power supply, a precision ammeter with a 0…25mA min. range. HD9009TR: a 7…30Vdc continuous voltage power supply, a precision voltmeter with a 0…1Vdc min. range. The calibration of the humidity sensor is carried out at two fi xed points: at 75.4%RH – always as fi rst point – and at 33%RH – second point. Procedure: 1. To access the panel board, unscrew grommet “A” (see fi g. 3) and hold the cable fi rmly to avoid twisting. Take off the rubber bulb and...

7. Wait 10 seconds until the measurement becomes steady, press the “CAL °C” key (calibration) and hold it down for min. 5 seconds, until the LED is off. When you release the key, the LED will fl ash twice to confi rm that programming took place. Now the procedure is over. 8. Check that the confi guration corresponds to the requested specifi cations, by setting the simulator (or connecting the precision resistances) at the values corresponding to the upper and full scale value and by checking the output with the ammeter 8HD9008TR) or with the voltmeter (HD9009TR). 9. Solder again the temperature...