3-36
D30 Line Distance Protection System
GE Multilin
3.3 DIRECT INPUT/OUTPUT COMMUNICATIONS
3 HARDWARE
3
3.3.8 IEEE C37.94 INTERFACE
The UR-series IEEE C37.94 communication modules (modules types 76, and 77) are designed to interface with IEEE
C37.94 compliant digital multiplexers or an IEEE C37.94 compliant interface converter for use with direct input and output
applications. The IEEE C37.94 standard defines a point-to-point optical link for synchronous data between a multiplexer
and a teleprotection device. This data is typically 64 kbps, but the standard provides for speeds up to 64
n
kbps, where
n
=
1, 2,…, 12. The UR-series C37.94 communication modules are either 64 kbps (with
n
fixed at 1) for 128 kbps (with
n
fixed
at 2). The frame is a valid International Telecommunications Union (ITU-T) recommended G.704 pattern from the stand-
point of framing and data rate. The frame is 256 bits and is repeated at a frame rate of 8000 Hz, with a resultant bit rate of
2048 kbps.
The specifications for the module are as follows:.
•
IEEE standard: C37.94 for 2
×
64 kbps optical fiber interface (for 76 and 77 modules)
•
Fiber optic cable type: 50 nm or 62.5 µm core diameter optical fiber
•
Fiber optic mode: multi-mode
•
Fiber optic cable length: up to 2 km
•
Fiber optic connector: type ST
•
Wavelength: 820 ±40 nm
•
Connection: as per all fiber optic connections, a Tx to Rx connection is required
The UR-series C37.94 communication module can be connected directly to any compliant digital multiplexer that supports
the IEEE C37.94 standard as shown below.
The UR-series C37.94 communication module can be connected to the electrical interface (G.703, RS422, or X.21) of a
non-compliant digital multiplexer via an optical-to-electrical interface converter that supports the IEEE C37.94 standard, as
shown below.
In 2008, GE Digital Energy released revised modules 76 and 77 for C37.94 communication to enable multi-ended fault
location functionality with firmware 5.60 release and higher. All modules 76 and 77 shipped since the change support this
feature and are fully backward compatible with firmware releases below 5.60. For customers using firmware release 5.60
and higher, the module can be identified with "Rev D" printed on the module and is to be used on all ends of D30 communi-
cation for two and three terminal applications. Failure to use it at all ends results in intermittent communication alarms. For
customers using firmware revisions below 5.60, it is not required to match the revision of the modules installed.
UR-series
device
IEEE C37.94
fiber interface
up to 2 km
842755A2.CDR
Digital
multiplexer,
IEEE C37.94
compliant
UR-series
device
up to 2 km
IEEE C37.94
converter
RS422
interface
842756A2.CDR
IEEE C37.94
fiber interface
Digital
multiplexer
with EIA-422
interface
Summary of Contents for D30D00HCHF8AH6AM6BP8BX7A
Page 10: ...x D30 Line Distance Protection System GE Multilin TABLE OF CONTENTS...
Page 374: ...5 248 D30 Line Distance Protection System GE Multilin 5 10 TESTING 5 SETTINGS 5...
Page 398: ...6 24 D30 Line Distance Protection System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6...
Page 410: ...7 12 D30 Line Distance Protection System GE Multilin 7 2 TARGETS 7 COMMANDS AND TARGETS 7...
Page 444: ...9 24 D30 Line Distance Protection System GE Multilin 9 5 FAULT LOCATOR 9 THEORY OF OPERATION 9...
Page 576: ...B 102 D30 Line Distance Protection System GE Multilin B 4 MEMORY MAPPING APPENDIX B B...
Page 616: ...D 10 D30 Line Distance Protection System GE Multilin D 1 IEC 60870 5 104 PROTOCOL APPENDIX D D...
Page 628: ...E 12 D30 Line Distance Protection System GE Multilin E 2 DNP POINT LISTS APPENDIX E E...
Page 636: ...F 8 D30 Line Distance Protection System GE Multilin F 3 WARRANTY APPENDIX F F...
Page 646: ...x D30 Line Distance Protection System GE Multilin INDEX...
