D20/D200
Installation and Operations Guide
GE Energy
994-0078-2.00-7 General
48
Full
Connections and Configuration
, continued
D20ME II Jumpering
, continued
SW1
RS-485 2W/4W
When set for RS-485 mode (see SW2), each serial communication port channel must
be set for either RS-485 2-wire with the switch ON, or RS-485 4-wire (RS422) with
the switch OFF. RS-232 is the factory default setting for the D20ME Processor with
the switch OFF.
Note: In order for RS485 (2-wire/4-wire) to operate, the RTS ON/OFF setting must
be enabled and both DCD and CTS must be disabled in Config Pro specific
to the protocol being used for that serial port. RTS must be toggled ON for
RS485 2-wire transmissions and may be set continuously ON for RS485 4-
wire data transmissions.
Note: When operating a serial communication channel in RS-232 mode always
have the corresponding switch OFF.
SW1 (pins)
Serial Comm Port
RS-485 2-
wire
RS-485 4-
wire
RS-232
1-16 1
ON
OFF
OFF
2-15 2
ON
OFF
OFF
3-14 3
ON
OFF
OFF
4-13 4
ON
OFF
OFF
5-12 5
ON
OFF
OFF
6-11 6
ON
OFF
OFF
7-10 7
ON
OFF
OFF
SW2
RS-485/RS-232
Mode Selection
SW2 allows each serial communication port channel to be set for either RS-485 (RS-
422) mode with the switch ON, or for the default setting of RS-232 mode with the
switch OFF.
JP10 (pins)
Serial Comm Port
RS-485(RS-422)
mode
RS-232 mode
1-16 1
ON OFF
2-15 2
ON OFF
3-14 3
ON OFF
4-13 4
ON OFF
5-12 5
ON OFF
6-11 6
ON OFF
7-10 7
ON OFF
