ABB Relion 670 series, Technical Reference Manual

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CAN Controller Area Network. ISO standard (ISO 11898) for serial
communication
CB Circuit breaker
CBM Combined backplane module
CCITT Consultative Committee for International Telegraph and
Telephony. A United Nations-sponsored standards body
within the International Telecommunications Union.
CCM CAN carrier module
CCVT Capacitive Coupled Voltage Transformer
Class C Protection Current Transformer class as per IEEE/ ANSI
CMPPS Combined megapulses per second
CMT Communication Management tool in PCM600
CO cycle Close-open cycle
Codirectional Way of transmitting G.703 over a balanced line. Involves two
twisted pairs making it possible to transmit information in
both directions
COMTRADE Standard Common Format for Transient Data Exchange
format for Disturbance recorder according to IEEE/ANSI
C37.111, 1999 / IEC60255-24
Contra-directional Way of transmitting G.703 over a balanced line. Involves four
twisted pairs, two of which are used for transmitting data in
both directions and two for transmitting clock signals
CPU Central processor unit
CR Carrier receive
CRC Cyclic redundancy check
CROB Control relay output block
CS Carrier send
CT Current transformer
CVT or CCVT Capacitive voltage transformer
DAR Delayed autoreclosing
DARPA Defense Advanced Research Projects Agency (The US
developer of the TCP/IP protocol etc.)
DBDL Dead bus dead line
DBLL Dead bus live line
DC Direct current
Section 23
1MRK505222-UUS C
Glossary
1216
Technical reference manual