• Definite time delay or Inverse Time Overcurrent (TOC/IDMT) delay for
both steps
• Second harmonic supervision is available in order to only allow
operation of the overcurrent stage(s) if the content of the second
harmonic in the measured current is lower than pre-set level
• Directional supervision is available in order to only allow operation of
the overcurrent stage(s) if the fault location is in the pre-set direction
(Forward or Reverse). Its behavior during low-level polarizing voltage is
settable (Non-Directional, Block, Memory)
• Voltage restrained/controlled feature is available in order to modify the
pick-up level of the overcurrent stage(s) in proportion to the magnitude
of the measured voltage
• Current restrained feature is available in order to only allow operation of
the overcurrent stage(s) if the measured current quantity is bigger than
the set percentage of the current restrain quantity.
2. Two undercurrent steps with the following built-in features:
• Definite time delay for both steps
3. Two overvoltage steps with the following built-in features
• Definite time delay or Inverse Time Overcurrent TOC/IDMT delay for
both steps
4. Two undervoltage steps with the following built-in features
• Definite time delay or Inverse Time Overcurrent TOC/IDMT delay for
both steps
All these four protection elements within one general protection function works
independently from each other and they can be individually enabled or disabled.
However, note that all these four protection elements measure one selected current
quantity and one selected voltage quantity (see table
43 and table 44). It is possible
to simultaneously use all four protection elements and their individual stages.
Sometimes, it is necessary to provide interaction between two or more protection
elements/stages within one CVGAPC function by appropriate IED configuration to
obtain desired application functionality.
12.1.2.1 Current and voltage selection for CVGAPC function
SEMOD53443-6 v4
CVGAPC function is always connected to three-phase current and three-phase
voltage input in the configuration tool, but it will always measure only the single
current and the single voltage quantity selected by the end user in the setting tool.
The user can select a current input, by a setting parameter CurrentInput, to measure
one of the current quantities shown in table
43.
Section 12 1MRK 506 369-UEN B
Multipurpose protection
566 Line distance protection REL670 2.2 IEC
Application manual
To Next Page
Loading...
