User Manual

E-M-HF4-V1_22

Rotronic AG

Bassersdorf, Switzerland

Document code

Unit

HygroFlex HF4 Humidity Temperature

Transmitters: User Guide

Instruction Manual

Document Type

Page

8 of 29

Document title

3.6 Service connector

The service connector is a UART digital interface (Universal Asynchronous Receiver Transmitter) with a mini-

USB type connector. This allows connecting the HF4 either to a PC running the ROTRONIC HW4 software or

to a probe input of another instrument that is compatible with the HygroClip 2 (HC2) probes. In both cases a

service cable is required. See “Maintenance” for the location of the service connector and for the type of

service cable to be used.

Connecting the HF4 to a PC is used to configure the HF4, gain access to the HF4 functions such as

humidity and temperature adjustment, read data from the HF4 on the PC and update the AirChip 3000

firmware.

Connecting the HF4 to the probe input of another instrument is useful only when the other instrument has

its own display and keypad, and has an internal menu equivalent to the menu of the HP23 hand-held

calibrator. The connection allows showing the data measured by the HF4 on the other instrument display

and also allows using the other instrument internal menu to do for example a humidity and temperature

adjustment of the HF4.

o HF45 (digital outputs): the digital interface (USB, Ethernet and RS-485) offers the same functionality as

the service connector but does not allow connecting the HF4 to a HP23 hand-held calibrator.

3.7 Sensor protection (dust filter)

The HF4 is supplied with a Polyethylene filter to protect the sensors against dust particles and high air

velocity.

4 User configurable settings and functions

The HF4 ships configured as specified on the customer order. Models with analog outputs can be installed

and used just as any conventional humidity and temperature transmitter and most users will never need to use

the HF4 configurable settings and functions. Models with a digital interface generally require some

configuration by the user.

Making use of the HF4 configurable settings and functions is entirely up to the user and the appropriate

settings depend on the user application. We have provided below a short description of the HF4 functions and

also indicated the factory default settings.