I.S. EN 60255-121:2014
Current
The latest, up-to-date edition.
MEASURING RELAYS AND PROTECTION EQUIPMENT - PART 121: FUNCTIONAL REQUIREMENTS FOR DISTANCE PROTECTION
Hardcopy , PDF
English
01-01-2014
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Only cited Standards give presumption of conformance to New Approach Directives/Regulations.
FOREWORD
1 Scope
2 Normative references
3 Terms and definitions
4 Specification of the function
5 Performance specifications
6 Functional tests
7 Documentation requirements
Annex A (informative) - Impedance characteristics
Annex B (informative) - Informative guide for
the behaviour of timers in distance protection
zones for evolving faults
Annex C (normative) - Setting example
Annex D (normative) - Calculation of mean, median
and mode
Annex E (informative) - CT saturation and influence
on the performance of distance relays
Annex F (informative) - Informative guide for testing
distance relays based on CT requirements specification
Annex G (informative) - Informative guide for
dimensioning of CTs for distance protection
Annex H (normative) - Calculation of relay settings
based on generic point P expressed in terms of
voltage and current
Annex I (normative) - Ramping methods for testing the
basic characteristic accuracy
Annex J (normative) - Definition of fault inception angle
Annex K (normative) - Capacitive voltage instrument
transformer model
Annex ZA (normative) - Normative references to
international publications with their
corresponding European publications
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