GE Multilin
D60 Line Distance Protection System
B-3
APPENDIX B
B.1 MODBUS RTU PROTOCOL
B
Table B–3: MODBUS RTU CRC-16 ALGORITHM
SYMBOLS:
-->
data transfer
A
16 bit working register
Alow
low order byte of A
Ahigh
high order byte of A
CRC
16 bit CRC-16 result
i,j
loop counters
(+)
logical EXCLUSIVE-OR operator
N
total number of data bytes
Di
i-th data byte (i = 0 to N-1)
G
16 bit characteristic polynomial = 1010000000000001 (binary) with MSbit dropped and bit order reversed
shr (x)
right shift operator (th LSbit of x is shifted into a carry flag, a '0' is shifted into the MSbit of x, all other bits
are shifted right one location)
ALGORITHM:
1.
FFFF (hex) --> A
2.
0 --> i
3.
0 --> j
4.
Di (+) Alow --> Alow
5.
j + 1 --> j
6.
shr (A)
7.
Is there a carry?
No: go to 8; Yes: G (+) A --> A and continue.
8.
Is j = 8?
No: go to 5; Yes: continue
9.
i + 1 --> i
10.
Is i = N?
No: go to 3; Yes: continue
11.
A --> CRC
Содержание D60
Страница 61: ...GE Multilin D60 Line Distance Protection System 2 31 2 PRODUCT DESCRIPTION 2 3 SPECIFICATIONS 2 ...
Страница 62: ...2 32 D60 Line Distance Protection System GE Multilin 2 3 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Страница 102: ...3 40 D60 Line Distance Protection System GE Multilin 3 3 DIRECT INPUT AND OUTPUT COMMUNICATIONS 3 HARDWARE 3 ...
Страница 134: ...4 32 D60 Line Distance Protection System GE Multilin 4 3 FACEPLATE INTERFACE 4 HUMAN INTERFACES 4 ...
Страница 508: ...5 374 D60 Line Distance Protection System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Страница 538: ...6 30 D60 Line Distance Protection System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Страница 610: ...10 8 D60 Line Distance Protection System GE Multilin 10 2 BATTERIES 10 MAINTENANCE 10 ...
Страница 622: ...A 12 D60 Line Distance Protection System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Страница 745: ...GE Multilin D60 Line Distance Protection System B 123 APPENDIX B B 4 MEMORY MAPPING B ...
Страница 746: ...B 124 D60 Line Distance Protection System GE Multilin B 4 MEMORY MAPPING APPENDIX B B ...
Страница 776: ...C 30 D60 Line Distance Protection System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Страница 792: ...E 10 D60 Line Distance Protection System GE Multilin E 1 IEC 60870 5 104 PROTOCOL APPENDIX E E ...
Страница 804: ...F 12 D60 Line Distance Protection System GE Multilin F 2 DNP POINT LISTS APPENDIX F F ...
Страница 826: ...xii D60 Line Distance Protection System GE Multilin INDEX ...