ROTRONIC HF3 - Manual (Page 21)

E-M-HF3-V1_22
Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF3 Transmitters and Thermo-
hygrostats: User Guide Instruction Manual
Document Type
Page 21 of 27
Document title
© 2009-2011; Rotronic AG E-M-HF3-V1_22
8 Maintenance
8.1 Service cable
IMPORTANT:
o Use service cable AC3009 with all 2-wire, loop powered transmitters. This cable powers up the
transmitter via the service connector. Do not use any other method for powering the transmitter when
using this cable AC3009 as this will create a ground loop and damage the transmitter. For the same
reasons do not use cable AC3006 with a 2-wire, loop powered transmitter.
o Use service cable AC3006 with all 3-wire transmitters as well as with the HF34 thermo-hygrostat.
This cable does not provide power to the transmitter and the transmitter should powered separately
when using this cable
Both cables AC3006 and AC3009 convert UART (service connector) to USB and are used to connect the
HF3 to a USB port of a PC running the ROTRONIC HW4 software. Prior to using any of these cables, the
ROTRONIC USB driver must be installed on the PC. Both the driver and the installation instructions
(document E-M-HW4v3-Main) are located on the HW4 CD.
As an alternative, cable AC2001 is used to connect the HF3 to a probe input of the HP23 hand-held
calibrator. For service purposes, the HP23 offers essentially the same functionality as the HW4 software.
8.2 Location of the service connector (mini-USB type)
WARNING: the service connector is a UART interface with a mini-USB connector type. Do not connect the
service connector directly to the USB port of a PC or hub.
8.2.1 Type R and S
The service connector (UART interface) is located at the bottom of the transmitter, on the left side.
8.2.2 Type D and W
The service connector (UART interface) is located inside of the enclosure and can be accessed after
removing the cover.
Service connector
HF33 HF34 HF32