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6.3 PC interface
Communication with a laptop or PC is carried out on the DIN Rail as in the field housing version optionally
on the terminals via an RS 485 or on the front side via a USB interface.
✔
The
RS 485 connection
is attached to the evaluation unit in the field housing at the ModBus A (+)
and ModBus B (-) terminals on the DIN Rail version, these connections are
nos. 12 and 11, accordingly.
RS 485 is a bus connection; the ModBus address and the baud rate can be set on the device. Upon
delivery, the communication parameters are set to:
•
ModBus address 1
•
Baud rate 9600, 8, E,1
An RS 485 to USB adapter can be purchased from ENVEA Process.
✔
For the USB connection to the DIN Rail version is a standard USB-A-B cable included. The USB
connection is a point-to-point connection that is not BUS-capable. The ModBus address and the baud
rate for the front-side connections cannot be changed and are always:
•
ModBus address 1 (or the device answers to all addresses)
•
Baud rate 9600, 8, E,1
When connected to the PC for the first time, any interface drivers enclosed with the evaluation unit
must be installed.
After starting the software, the communication parameters must first be entered accordingly. These
can be found in the top left of the program window. The COM port to be set is displayed in the device
manager.
Communication is established by clicking on “Read device”. The acknowledgement message
“Parameter read in” is displayed. If an error message is displayed instead, check the
communication parameters and cable connections between the PC and the evaluation unit.
