IEC 60427:2000

FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Definitions
4 Synthetic testing techniques and methods -
    Short-circuit breaking tests
    4.1 Basic principles and general requirements for
          synthetic breaking test methods
    4.2 Synthetic test circuits and related specific
          requirements for breaking tests
5 Short-circuit making tests
    5.1 Basic principles and general requirements for
          synthetic making test methods
    5.2 Synthetic test circuit and related specific
          requirements for making tests
6 Specific requirements for synthetic tests for making and
    breaking performance related to the requirements of
    subclauses 6.102 to 6.111 inclusive of IEC 60056
Annexes
 AA (informative) Current distortion
 BB (informative) Current injection methods
 CC (informative) Voltage injection methods
 DD (informative) Duplicate circuit (transfomer or
                     Skeats circuit)
 EE (normative) Information to be given and results to
                     be recorded for synthetic tests
 FF (informative) Special procedures for testing
                     circuit-breakers having parallel
                     breaking resistors
 GG (normative) Synthetic methods for capacitive-
                     current switching
 HH (informative) Reignition methods to prolong arcing
Figures
 1 - Interrupting process: basic time intervals
 2 - Example of recovery voltage
 3 - Equivalent surge impedance within the voltage
     circuit of current injection scheme
 4 - Making process: basic time intervals
 5 - Maximum allowable pre-arcing time for valid
     making test at reduced voltage
 6 - Synthetic make circuit and waveforms
 AA.1a - Direct circuit, simplified diagram
 AA.1b - Prospective short-circuit current
 AA.1c - Distortion current
 AA.1d - Distortion current
 AA.2a - Simplified circuit diagram
 AA.2b - Current and arc-voltage characteristics for
         symmetrical current
 AA.2c - Current and arc-voltage characteristics for
         asymmetrical current
 AA.3a to AA.3d - Reduction of amplitude and duration
                  of final current loop of arcing
 BB.1 - Typical current injection circuit with voltage
        circuit in parallel with the test circuit breaker
 BB.2 - Injection timing for current injection scheme
        with circuit BB.1
 BB.3 - Typical current injection circuit with voltage
        circuit in parallel with the auxiliary
        circuit-breaker
 BB.4 - Injection timing for current injection scheme
        with circuit BB.3
 BB.5 - Examples of the determination of the interval of
        significant change of arc-voltage from the
        oscillograms
 CC.1 - Typical voltage injection circuit diagram with
        voltage circuit in parallel with the auxiliary
        circuit-breaker (simplified diagram)
 CC.2 - TRV waveshapes in a voltage injection circuit
        with the voltage circuit in parallel with the
        auxiliary circuit-breaker
 DD.1 - Transformer or Skeats circuit
 DD.2 - Triggered transformer or Skeats circuit
 GG.1 - Synthetic testing scheme (parallel mode)
 GG.2 - Synthetic testing scheme with an inductive current
        circuit and with facility to adjust a voltage jump
 GG.3 - Synthetic voltage injection circuit providing a
        voltage jump
 GG.4 - Synthetic current injection scheme
 GG.5 - Synthetic test circuit (serial mode) to apply to
        both sides of the test breaker the normal system
        recovery voltage
 GG.6 - Synthetic testing scheme for making
 HH.1 - Typical reignition circuit diagram for prolonging
        arc-duration
 HH.2 - Combined Skeats and current injection circuits
 HH.3 - Typical waveforms obtained on an asymmetrical test
        using the circuit in figure HH.2

Applies to a.c. circuit-breakers within the scope of IEC 60056(Clause 1). It provides the general rules for testing a.c. circuit-breakers, for making and breaking capacities over the range of test-duties described in Subclauses 6.102 to 6.111 of IEC 60056, by synthetic methods. The purpose of this standard is to establish criteria for synthetic testing and for the proper evaluation of results. Such criteria will establish the validity of the test method without imposing restraints on innovation of test circuitry.