WIKA DI35 - Manual (Page 17)

6 Commissoning, operation
WIKA operating instructions digital indicator model DI35-M 17
Serial interface
RS 232:
The lines for the RS 232 interface must be connected 1:1, TxD to TxD and
RxD to RxD.
RS 485:
The RS 485 interface is connected via a shielded data line with a twisted pair.
At each end of the bus, a termination of the bus lines must be connected.
This is necessary to guarantee reliable data transmission on the bus. For this,
a resistance of 120 Ohm is inserted between the lines Data B(+) and Data
A(–).
CAUTION!
The potential reference can lead to a compensating current
(interface
⇔ measuring input) with a non-galvanic insulated
interface and can thus affect the measuring signals