GE Multilin
B90 Low Impedance Bus Differential System
3-29
3 HARDWARE
3.3 DIRECT INPUT/OUTPUT COMMUNICATIONS
3
6.
Replace the top cover and the cover screw.
7.
Re-insert the G.703 module. Take care to ensure that the
correct
module type is inserted into the
correct
slot position.
The ejector/inserter clips located at the top and at the bottom of each module must be in the disengaged position as
the module is smoothly inserted into the slot. Once the clips have cleared the raised edge of the chassis, engage the
clips simultaneously. When the clips have locked into position, the module is fully inserted.
Figure 3–31: G.703 TIMING SELECTION SWITCH SETTING
c) G.703 OCTET TIMING
If octet timing is enabled (ON), this 8 kHz signal is asserted during the violation of bit 8 (LSB) necessary for connecting to
higher order systems. When B90s are connected back-to-back, octet timing is disabled (OFF).
d) G.703 TIMING MODES
There are two timing modes for the G.703 module: internal timing mode and loop timing mode (default).
•
Internal Timing Mode:
The system clock is generated internally. Therefore, the G.703 timing selection should be in
the internal timing mode for back-to-back (UR-to-UR) connections. For back-to-back connections, set for octet timing
(S1 = OFF) and timing mode to internal timing (S5 = ON and S6 = OFF).
•
Loop Timing Mode:
The system clock is derived from the received line signal. Therefore, the G.703 timing selection
should be in loop timing mode for connections to higher order systems. For connection to a higher order system (UR-
Table 3–3: G.703 TIMING SELECTIONS
SWITCHES
FUNCTION
S1
OFF
octet timing disabled
ON
octet timing 8 kHz
S5 and S6
S5 = OFF and S6 = OFF
loop timing mode
S5 = ON and S6 = OFF
internal timing mode
S5 = OFF and S6 = ON
minimum remote loopback mode
S5 = ON and S6 = ON
dual loopback mode
Cover screw
Top cover
Bottom cover
Ejector/inserter clip
Ejector/inserter clip
Timing selection
switches
Channel 1
Channel 2
FRONT
REAR
831774A3.CDR
Summary of Contents for B90
Page 10: ...x B90 Low Impedance Bus Differential System GE Multilin TABLE OF CONTENTS ...
Page 284: ...5 166 B90 Low Impedance Bus Differential System GE Multilin 5 8 TESTING 5 SETTINGS 5 ...
Page 334: ...10 8 B90 Low Impedance Bus Differential System GE Multilin 10 2 BATTERIES 10 MAINTENANCE 10 ...
Page 338: ...A 4 B90 Low Impedance Bus Differential System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Page 460: ...C 30 B90 Low Impedance Bus Differential System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Page 476: ...E 10 B90 Low Impedance Bus Differential System GE Multilin E 1 IEC 60870 5 104 APPENDIX E E ...
Page 502: ...viii B90 Low Impedance Bus Differential System GE Multilin INDEX ...
