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GENERAL
D400 SUBSTATION GATEWAY USER’S MANUAL
RS-485 CONNECTIONS
CHAPTER 4: CONNECTING TO DEVICES AND NETWORKS
The required RS-232 cable is a serial null modem, DB-9F to DB-9M cable. The cables must
be shielded and DB-9S connector covers must provide EMC shielding (e.g. metallized
plastic or die-cast metal covers).
See “RS-232 adapter” on page 33 for configuration options.
To connect RS-232
type devices to the
RS-232 adapter
Use the cable connection shown in Figure 30
Figure 30: RS-232 cable connection
Table 10: RS-232 Port DB-9 Connector Signal Definitions
a
DCD output not supported in DCE mode.
RS-485 connections
The D400 accepts connections to RS-485 2-wire and 4-wire type devices through the RS-
485 Adapter. The RS-485 Adapter (GE Item No. 520-0208LF) plugs into any serial
communication slot (slots 1 through 8) on the D400. It contains two independently isolated
RS-485 channels on a single terminal block: Channel 1 on terminals TB1-1 through TB1-5
and Channel 2 on terminals TB1-6 through TB1-10. Terminal blocks accept a range of 24-
14 AWG [0.2-2.1 mm²] Recommended wire strip length is 0.2" [5.0 mm]. Screws shall be
torqued with tool setting of 4.2 in-lb [0.46 Nm]. A 3.0 to 3.5 mm flat screwdriver tip is
recommended.
The transceiver in 2-wire mode and the receiver in 4-wire mode present 1 unit load (UL),
nominally 12 KOhm, to the external network with switches SW3/SW4 all off.
See “RS-485 adapter” on page 37 for configuration options.
Pin
Numbers
DTE (default)
DCE
Signal Acronym
Signal Flow
Signal Acronym
Signal Flow
1
DCD
IN from DCE
a
a
2
RXD
IN from DCE
RXD
OUT to DTE
3
TXD
OUT to DCE
TXD
IN from DTE
4
DTR
OUT to DCE
DTR
IN from DTE
5
Signal GND
-
Signal GND
-
6
DSR
IN from DCE
DSR
OUT to DTE
7
RTS
OUT to DCE
RTS
IN from DTE
8
CTS
IN from DCE
CTS
OUT to DTE
9
Not connected
-
Not connected
-
Relay
1
5
6
9
1
5
6
9
2
3
5
7
8
7
8
2
3
5