GE 90-30 PLC Series Installation And Hardware Manual page 365

B
Table B-3. Jumper Configuration for RS-422/RS-485 to RS-232 Converter
Jumper
JP2
JP3
JP4
*Refer to the documentation for your serial device for signal requirements.
B-8 Series 90-30 PLC Installation and Hardware Manual – August 2002
Label Jumper
Position
DCD 1 2 3 Default position 1 and 2 is used when the device communicating
with the PLC does not supply the Carrier Detect signal. JP2 forces
the DCD signal active on the RS-485 port.
1 2 3 Use jumper positions 2 and 3 if the device does supply the Carrier
Detect signal. This allows the programming device to control
DCD.
MODEM 1 2 3
Default position 1 and 2 is used when an attached Modem does not
require the Clear To Send (CTS) signal. This allows the
programming device to control the RTS signal.
1 2 3 Jumper positions 2 and 3 are used when the attached Modem does
require the CTS signal (most modems require this signal). Forces
RTS to be continually active.
ATTACH 1 2 3 Default position 1 and 2 is used for most applications
communicating with the PLC via a serial programming device.
1 2 3 Jumper positions 2 and 3 are used if the device communicating with
the PLC is intended to emulate the HHP protocol.
Description*
GFK-0356Q