E-m-hf7-v1_24 – ROTRONIC HF7 User Manual
Page 15
E-M-HF7-V1_24
Rotronic AG
Bassersdorf, Switzerland
Document code
Unit
HygroFlex HF7 Humidity Temperature
Transmitters: User Guide
Instruction Manual
Document Type
Page 15 of 23
Document title
© 2009-2011; Rotronic AG E-M-HF7-V1_24
Terminal block diagram
Measuring humidity or temperature only
Operation of the HF73 does not require both current loops to be closed. When using the HF73 to measure
either humidity only or temperature only, close only the loop that is being used.
Using the ROTRONIC HW4 software, any unused output of the HF73 can be disabled.
6.3.3
Grounding (all models)
We generally recommend grounding the (-) side of the power supply, especially if the electronics will be
subjected to a low humidity environment (35 %RH or less).
Terminals
Description
K1-1: OUT1
Relative humidity or dew point (+)
K1-2: OUT2
Temperature output (+)
K1-3: GND
Ground (tied with other GND)
K2-1: PWR
Power supply: 15…40 VDC (+)
or 12…28 VAC (Phase)
K2-2: GND
Power supply (-) or neutral
(tied with other GND)