Pleiger Elektronik
GmbH & Co. KG
Page: 40
Manual for 362MC
Edition: 6/2007 Subject to modifications
Overview of communication protocols
A description of the transmission procedures and the protocol assignments is available on request.
Appendix B3:
Hardware extension - RS485/RS422 communication interface
A module incorporating a communication interface is available for the 362MC, for installation at the
factory. The interface is isolated, and in the standard version it is wired up as an RS485 interface
(2-wire). A special variant with RS422 interface (4-wire) is available. The communication interface
enables the transmission of process data and setpoints from the two controllers of the 362MC.
Terminal assignments
Connection is carried out by means of
terminals 25-28, which are marked
Module 1
, in accordance with the
table opposite.
Connection and wiring
The diagrams below show the
connection configuration. Connection
is carried out with shielded, twisted-pair cabling with a min. wire cross-section of 0.22mm². 120 ohm is
recommended as the terminating impedance for the RS485 interface.
Parameterisation
The transmission speed
Baudr
and the
user address
Slave no
of the controller
are set via two additional parameters in
the
Profile
commissioning menu:
Connection table
(362MC hardware extension)
(excerpt)
- RS485/RS422 communication interface -
Terminal Signal name
25
d
+Rx/Tx > transmitted and received data, RS485
26
c
- Rx/Tx
(in RS422 version
Rx
= received data)
27
b
+Rx/Tx < transmitted and received data, RS485
28
a
- Rx/Tx
(in RS422 version
Tx
= transmitted data)
+Rx
-Rx
+Tx
-Tx
Example: RS422-Interface
362MC
Slave n
362MC
Slave 2
362MC
Slave 1
Example: RS485-Interface
Data direction:
362MC -> Master
- confirmation setpoint message, controller 1
- confirmation setpoint message, controller 2
- process data and status, controller 1
- process data and status, controller 2
Data direction:
Master -> 362MC
- setpoints and alarm limits, controller 1
- setpoints and alarm limits, controller 2
- request process data and status, controller 1
- request process data and status, controller 2
Parameter
Value
Baudr
Baudr
Baudr
Baudr
Baudr
2400, 4800, 9600, 19200
SlaveNo
SlaveNo
SlaveNo
SlaveNo
SlaveNo
1...127
