Signal Assignments; Terminal Board Screw Connections; Termination Jumpers - GE Mark VIeS System Manual

9.3.3 Operation
The SSCA includes six connection points for each of the six serial communication channels. The points include four signal
lines A-D, a signal return, and a shield common (SCOM).
Protocol A
RS-422 TX+
RS-485 TX/RX+
RS-232C DTR/RTS
The return for RS-232C is through the terminal called Ret. The signals for all six serial communication channels are arranged
in the same order, which is SCOM, A, B, C, D, Ret when viewed from left to right.
The groups of six signals for a serial channel are assigned to terminals adjacent to each other. When viewed from left to right,
the channels on the bottom set of terminals are 5, 4, and 1. The top set of terminals contain channels 6, 3, and 2 when viewed
from left to right. The board SCOM connections are grouped on the right side of the terminals. A signal location diagram is
included on the SSCA.
Connection Port 1
SCOM 26
PT_A 28
PT_B 30
PT_C 32
PT_D 34
Ret 36
When using RS-422 or RS-485, a termination resistor must be provided at either end of a transmission line. The SSCA
provides selectable termination resistors for each pair of signal lines. Jumpers JP1A and JP1B apply or remove the
termination resistors between signals A-B and C-D. The same function is repeated for each serial communication channel.
The default jumper position includes a disconnected termination resistor. The SSCA is clearly marked to display the
relationship of the termination jumpers and the serial communication channel signals as displayed in the following figure.
294 GEH-6855_Vol_II

Signal Assignments

B C
TX- RX+
TX/RX- Jumper from A
TX CTS

Terminal Board Screw Connections

Port 2 Port 3
25 13
27 15
29 17
31 19
33 21
35 23

Termination Jumpers

GEH-6855_Vol_II Mark VIeS Functional Safety Systems Volume II
D Cable Length
RX- Up to 305 m (1000 ft)
Jumper from B Up to 305 m (1000 ft)
RX Up to 15 m (50 ft) or 2500 pF
Port 4
14
16
18
20
22
24
Public Information
Port 5 Port 6
2 1
4 3
6 5
8 7
10 9
12 11