Manual

E-M-HF5-V1_25
Rotronic AG
Bassersdorf, Switzerland
Document code
Unit
HygroFlex HF5 Humidity Temperature
Transmitters: User Guide
Instruction Manual
Document Type
Page
16 of 30
Document title
© 2009-2013; Rotronic AG E-M-HF5-V1_25
6.4 Wiring
6.4.1 HF52: 2-wire, loop powered transmitter
Electrical diagram
The maximum permissible cable length connecting
the HF52 to other devices is determined by the total
resistance resulting from the addition of the cable
resistance and that of the devices connected in series
with the unit. This resistance should not exceed 500
ohms.
Terminal block diagram
Note: connect the + of the power supply to only one of the V+ terminals. The two terminals marked V+ are
internally connected.
Measuring humidity or temperature only
Unless configured to measure either humidity only or temperature only, proper operation of the HF52 requires
both current loops to be closed. The HF52 can be directly ordered from the factory to measure either humidity
or temperature only. When necessary, any unused output of the HF52 can be disabled with the ROTRONIC
HW4 software. When the HF52 is configured with one of the two outputs disabled, close only the loop that is
being used.
Terminals
Description
K2-2: T-OUT
Temperature output (+)
OUT-2
K2-1: V+
Power supply: 10…28 VDC (+)
Terminals
Description
K1-2: H-OUT
Relative humidity or dew point (+)
OUT-1
K1-1: V+
Power supply: 10…28 VDC (+)