6.2
Current circuit supervision CCM
6.2.1
Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Current circuit supervision
CCRDIF
MCS 3I
CCM
6.2.2
Function block
GUID-7695BECB-3520-4932-9429-9A552171C0CA-ANSI V1 EN
Figure 189:
Function block
6.2.3
Functionality
The current circuit supervision function CCM is used for monitoring current transformer
secondary circuits.
CCM calculates internally the sum of phase currents (I_A, I_B and I_C) and compares the
sum against the measured single reference current (I_REF).The reference current must
originate from other three-phase CT cores than the phase currents (I_A, I_B and I_C) and
it is to be externally summated, that is, outside the protection relay.
CCM detects a fault in the measurement circuit and issues an alarm or blocks the
protection functions to avoid unwanted tripping.
It must be remembered that the blocking of protection functions at an occurring open CT
circuit means that the situation remains unchanged and extremely high voltages stress the
secondary circuit.
6.2.4
Operation principle
The function can be enabled and disabled with the
Operation
setting. The corresponding
parameter values are “Enable” and “Disable”.
Section 6
1MRS240050-IB C
Supervision functions
362
REF615R
Technical Manual
Содержание RELION REF615R
Страница 1: ... RELION PROTECTION AND CONTROL REF615R Technical Manual ...
Страница 2: ......
Страница 27: ...Section 18 Glossary 653 Table of contents REF615R 21 Technical Manual ...
Страница 28: ...22 ...
Страница 36: ...30 ...
Страница 46: ...40 ...
Страница 115: ...3 15 4 Settings 1MRS240050 IB C Section 3 Basic functions REF615R 109 Technical Manual ...
Страница 118: ...112 ...
Страница 318: ...312 ...
Страница 388: ...382 ...
Страница 456: ...450 ...
Страница 520: ...514 ...
Страница 652: ...646 ...
Страница 656: ...650 ...
Страница 658: ...652 ...
Страница 663: ...657 ...