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

5 of 30

Document title

2.1 Display and keypad option

The LC display option for the HF53 and HF55 has a

backlight. The LC display option for the HF52 does

not have a backlight.

The upper line corresponds to relative humidity or

dew / frost point and the bottom line corresponds to

temperature.

The display can be configured to show a trend indicator on each line:

▲: increasing value

▼: decreasing value

In the event of an alarm the display shows the symbol [ ! ] to the right of the value.

For instructions see the following HW4 manual: E-M-HW4v3-F2-005.

3 General description

3.1 Power supply options

Depending on the circuit type, the HF5 requires the following power supply:

a) HF52 (2-wire, loop powered): 10…28 VDC - depending on the load connected to the output(s). The

minimum supply voltage can be determined as follows:

V min = 10 V + (0.02 x Load*) *Load resistance in ohms.

For the maximum load of 500 , the minimum supply voltage is 10 + (0.02 x 500) = 20 VDC. With both

output circuits closed, the maximum current consumption is 40 mA.

b) HF53 (3-wire with analog outputs):

- Option 1, standard power supply: 15 to 40 VDC or 12 to 28 VAC

- Option 2: galvanically isolated power supply: 9 to 36 VDC or 7 to 24 VAC

With both output circuits closed, the typical current consumption is 100 mA.

Please verify the product identification label to determine which power supply option is installed on your

transmitter.

c) HF55 (3-wire) with digital outputs:

- Option 1, standard power supply: 5 to 40 VDC or 12 to 28 VAC

- Option 2: galvanically isolated power supply: 9 to 36 VDC or 7 to 24 VAC

- Option 3: PoE (power over Ethernet). This option is not available with units equipped with a RS-485

interface. Any unit equipped with the PoE option can be powered only via a LAN.