GE Grid Solutions
D25
User's Manual
GE Information
994-0081-3.00-21
71
Communications Ports,
Continued
Table: UTC
Port Pinout
How to connect to the UTC Port DB-9 connector for either RS-232 or RS-422
interface.
Note
: Pins 7 and 8 are tied together internally.
DB-9 Pin
RS-422 Signal
RS-232 Signal
1
T_RX+
N/C
2
T_RX-
RX
3
N/C
N/C
4
N/C
N/C
5
COM GND
COM GND
6
CLKE+
N/C
7
CLKE-
N/C
8
N/C
CTS
9
EARTH GND
EARTH GND
COM3 and
COM4
IED1 and IED2
Serial Ports
Two general-purpose, on-board communication ports are available on the
back panel of the D25, and use female DB-9-F style connectors. The IED
ports provide:
•
Variable communication parameters
•
Optional software flow control
•
Optional hardware flow control
•
Out-of-sequence transmission of one byte of data
•
Support for several I/O timers
Transmission of break characters
Both IED ports RS-232 and RS-485 (for multi-drop applications) are
supported on the same physical connector.
Note
:
The input resistance 12 KΩ is used for all serial ports in D25
(UTC/IED/XCOM) when configured as RS485. The typical resistance
is 24 KΩ, but use 12 KΩ as m
aximum burden. This is very important
for daisy chaining D25s, especially for IRIG-B signals.
IED Serial
Ports Options
The COM3 and COM4 serial ports are programmed via SGConfig for:
−
RS-232 or RS-485 selection
−
RS-485 2-Wire / 4-Wire selection
Note
: The 2 to 4- Wire selection in SGConfig
Device Properties
only
affects the internal software control (handshaking) of the interface.
It
does not
change the physical characteristics of the communication
ports.
Summary of Contents for D25
Page 170: ......
