IEC 61540:2023

IEC 61540 ®
Edition 2.0 2023-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Portable residual current devices (PRCDs) without integral overcurrent
protection for household and similar use

Dispositifs différentiels portables à courant résiduel (PCDM) sans protection
incorporée contre les surintensités pour usages domestiques et analogues

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IEC 61540 ®
Edition 2.0 2023-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Portable residual current devices (PRCDs) without integral overcurrent

protection for household and similar use

Dispositifs différentiels portables à courant résiduel (PCDM) sans protection

incorporée contre les surintensités pour usages domestiques et analogues

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.01  ISBN 978-2-8322-7185-8

– 2 – IEC 61540:2023 © IEC 2023
CONTENTS
FOREWORD . 10
INTRODUCTION . 12
1 Scope . 13
2 Normative references . 14
3 Terms and definitions, symbols and abbreviated terms . 15
3.1 Definitions relating to plugs and socket-outlets . 15
3.2 Definitions relating to residual current devices (RCDs) . 16
3.2.1 Definitions relating to currents flowing from live parts to earth . 16
3.2.2 Definitions relating to the energization of a residual current device
(RCD) . 17
3.2.3 Definitions relating to the operation and to the functions of a residual
current device . 17
3.2.4 Definitions relating to values and ranges of energizing quantities . 18
4 Classification . 18
4.1 According to the type of connection . 18
4.1.1 PRCD intermediate adaptor . 18
4.1.2 Non-rewireable residual current-protected cord extension sets . 19
4.1.3 Residual current-protected plugs . 19
4.1.4 In-line PRCDs . 19
4.2 According to the type of terminals . 19
4.3 According to behaviour after opening automatically in case of failure of the
line voltage . 19
4.4 According to their operating characteristics and behaviour in presence of DC
components . 19
4.5 According to the ambient air temperature . 20
4.5.1 For use between −5 °C and +40 °C . 20
4.5.2 For use between −25 °C and +40 °C . 20
4.6 Classification according to the protective conductor path . 20
4.6.1 PRCDs with switched protective conductor . 20
4.6.2 PRCDs with non-switched protective conductor . 20
4.7 According to the supply . 20
4.7.1 PRCDs supplied from one phase and neutral (LNSE or LNE) . 20
4.7.2 PRCDs supplied from two phases (LLSE or LLE) . 20
4.8 According an additional function of detecting faults on the supply side . 20
4.8.1 PRCDs not providing an additional function of detecting faults on the
supply side . 20
4.8.2 PRCDs providing an additional function of detecting faults on the supply
side with a defined behaviour in case of supply failures or miswiring
(PRCD-S) . 20
5 Characteristics of PRCDs . 20
5.1 Summary of characteristics . 20
5.2 Rated quantities and other characteristics . 21
5.2.1 Rated voltage . 21
5.2.2 Rated current (I ) . 21
n
5.2.3 Rated residual operating current (I ) . 21
Δn
5.2.4 Rated residual non-operating current (I ) . 21
Δno
5.2.5 Rated frequency . 21

5.2.6 Rated making and breaking capacity (I ) . 22
m
5.2.7 Rated residual making and breaking capacity (I ) . 22
Δm
5.2.8 Operating characteristics in case of residual currents comprising a DC
component . 22
5.3 Standard and preferred values . 22
5.3.1 Preferred values of rated operational voltage (U ) . 22
e
5.3.2 Standard values of rated current (I ) . 22
n
5.3.3 Standard values of rated residual operating current (I ) . 23
Δn
5.3.4 Standard value of residual non-operating current (I ) . 23
Δno
5.3.5 Standard minimum value of the non-operating overcurrent through the
PRCD . 23
5.3.6 Preferred values of rated frequency . 23
5.3.7 Minimum value of the rated making and breaking capacity (I ) . 23
m
5.3.8 Minimum value of the rated residual making and breaking capacity
(I ) . 23
Δm
5.3.9 Standard value of the rated conditional short-circuit current (I ) . 24
nc
5.3.10 Standard value of the rated conditional residual short-circuit current

(I ) . 24
Δc
5.3.11 Standard values of maximum break time. 24
5.4 Coordination with short-circuit protective devices (SCPDs) . 24
5.4.1 General . 24
5.4.2 Rated conditional short-circuit current (I ) . 24
nc
5.4.3 Rated conditional residual short-circuit current (I ) . 24
Δc
6 Marking and other product information . 24
6.1 Information and marking for PRCDs . 24
6.2 Information to be provided in an instruction sheet . 27
7 Standard conditions for operation in service and for installation . 27
7.1 Standard conditions . 27
7.2 Conditions for installations . 28
7.3 Pollution degree . 28
8 Requirements for construction and operation . 28
8.1 Mechanical design . 28
8.1.1 General . 28
8.1.2 Plug part, socket-outlet parts and RCD part(s) . 29
8.1.3 Mechanism . 34
8.1.4 Clearances and creepage distances (see Annex C) . 35
8.1.5 Screws, current-carrying parts and connections . 37
8.1.6 Terminals for external conductors for rewireable PRCDs . 37
8.1.7 Terminations for non-rewireable PRCDs . 39
8.1.8 Current-carrying parts . 39
8.2 Protection against electric shock . 40
8.2.1 General . 40
8.2.2 Requirements relating to plugs and socket-outlets, whether
incorporated or not in integral items . 40
8.3 Dielectric properties . 42
8.4 Temperature rise . 42
8.4.1 Temperature rise limits . 42

– 4 – IEC 61540:2023 © IEC 2023
8.4.2 Ambient air temperature . 42
8.5 Operating characteristic . 42
8.6 Mechanical and electrical endurance . 42
8.7 Performance at short-circuit currents . 43
8.8 Resistance to mechanical shock and impact . 43
8.9 Resistance to heat . 43
8.10 Resistance to abnormal heat and to fire . 43
8.11 Test device . 43
8.11.1 General . 43
8.11.2 Test function . 43
8.12 Behaviour of PRCDs in case of failure of line voltage . 44
8.13 Behaviour of PRCDs in case of overcurrent in the main circuit . 44
8.14 Resistance of PRCDs against unwanted tripping due to surge currents to
earth resulting from impulse voltages . 44
8.15 Behaviour of PRCDs in case of an earth fault current comprising a DC
component . 44
8.16 Reliability . 44
8.17 Resistance to tracking . 44
8.18 Electromagnetic compatibility (EMC) . 44
8.19 Standing current in the protective conductor . 45
8.20 Electrical performance . 45
8.20.1 Protective conductor path . 45
8.20.2 Contact mechanism . 45
8.20.3 Operation with supply failure and hazardous live protective conductor
conditions . 46
8.20.4 Behaviour of PRCDs in case of external fault current in the protective
conductor . 46
9 Test . 46
9.1 General . 46
9.1.1 Characteristics of PRCDs checked by means of type tests . 46
9.1.2 For certification purposes, type tests to be carried out in test sequences . 47
9.1.3 Routine tests . 48
9.2 Test conditions . 48
9.3 Test of indelibility of marking . 48
9.4 Test of reliability of screws, current-carrying parts and connections . 49
9.5 Test of reliability of terminals for external conductors . 50
9.6 Verification of protection against electric shock . 51
9.6.1 Test with conductors of the smallest and largest cross-sections . 51
9.6.2 Test with plug completely withdrawn . 52
9.6.3 Test with engagement surface in horizontal position . 52
9.6.4 Verification of the resistance between the earthing terminal and the
accessible metal part . 52
9.6.5 Verification of the isolation between the earthing terminal and the
accessible metal part . 52
9.6.6 Stray wire test for rewireable PRCDs . 52
9.6.7 Stray wire verification for non-rewireable PRCDs . 53
9.6.8 Verification of high electrical resistance of the conductive operating
means . 53
9.7 Test of dielectric properties . 53
9.7.1 Resistance to humidity . 53

9.7.2 Insulation resistance of the main circuit . 54
9.7.3 Dielectric strength of the main circuit . 54
9.7.4 Secondary circuit of detection transformers . 55
9.7.5 Verification of impulse withstand voltages . 55
9.8 Temperature-rise test . 58
9.8.1 Test conditions . 58
9.8.2 Ambient air temperature . 58
9.8.3 Test procedure . 59
9.8.4 Measurement of the temperature-rise of different parts . 59
9.8.5 Temperature-rise of a part . 59
9.9 Verification of the operating characteristic . 59
9.9.1 Test circuit . 59
9.9.2 Off-load tests with residual sinusoidal alternating currents at the
reference temperature of (20 ± 2) °C . 59
9.9.3 Verification of the correct operation with load at the reference
temperature . 60
9.9.4 Tests at the temperature limits . 61
9.9.5 Additional tests for PRCDs classified according to 4.8.2 . 61
9.9.6 Verification of protective conductor contact behaviour . 64
9.9.7 Verification of behaviour in case of external fault current in the
protective conductor . 64
9.9.8 Verification of standing current in the protective conductor . 65
9.10 Verification of mechanical and electrical endurance . 65
9.10.1 Normal operation of socket-outlets and plugs of the PRCD . 65
9.10.2 Test of the RCD part of the PRCD . 66
9.11 Verification of the behaviour of the PRCD under overcurrent conditions . 67
9.11.1 List of the overcurrent tests . 67
9.11.2 Short-circuit tests . 67
9.11.3 Verification of the making and breaking capacity of the plug and socket-

outlet(s) of the PRCD, separate or incorporated in integral items . 72
9.12 Verification of resistance to mechanical shock and impact . 72
9.12.1 General . 72
9.13 Test of resistance to heat . 75
9.14 Resistance of insulating material to abnormal heat and to fire . 76
9.14.1 General . 76
9.14.2 Glow-wire test. 76
9.15 Verification of the trip-free mechanism . 77
9.15.1 General test conditions . 77
9.15.2 Test procedure . 77
9.16 Verification of the test device . 77
9.16.1 Verification of the operation of the test device to disconnect the load . 77
9.16.2 Verification of the ampere-turns . 77
9.17 Verification of the behaviour of PRCDs in case of failure of the line voltage . 77
9.17.1 Determination of the limiting value of the line voltage (U ) . 77
x
9.17.2 Verification of the behaviour in case of failure of the line voltage . 78
9.17.3 Verification of the re-closing of PRCDs classified according to 4.3.2 at
restoration of the line voltage after automatic opening on failure of the

line voltage . 79
9.18 Verification of limiting values of the non-operating current under overcurrent
conditions . 79

– 6 – IEC 61540:2023 © IEC 2023
9.19 Verification of resistance against unwanted tripping due to surge currents to
earth resulting from impulse voltages for PRCDs of I ≥ 0,010 A . 79
Δn
9.20 Verification of the correct operation with residual currents having a DC
component for PRCDs according to 4.4.2 . 79
9.20.1 General . 79
9.20.2 Verification of the correct operation in case of a continuous rise of a
residual pulsating direct current . 79
9.20.3 Verification of the correct operation in case of suddenly appearing
residual pulsating direct currents . 80
9.20.4 Verification at the reference temperature of the correct operation with
load . 80
9.20.5 Verification of the correct operation in case of residual pulsating direct
currents superimposed by a smooth direct current of 0,006 A . 80
9.21 Verification of reliability . 81
9.21.1 Climatic test. 81
9.21.2 Test with temperature of 40 °C . 82
9.22 Verification of ageing . 83
9.23 Resistance to tracking . 84
9.24 Test on pins provided with insulating sleeves . 84
9.25 Test of mechanical strength of non-solid pins of plugs and portable socket-
outlets . 84
9.26 Verification of the effects of strain on the conductors . 84
9.27 Checking of the torque exerted by plug-in PRCDs on fixed socket-outlets . 85
9.28 Tests of the cord anchorage. 85
9.29 Flexing test of non-rewireable PRCDs . 86
9.30 Verification of the electromagnetic compatibility (EMC) . 87
9.31 Tests replacing verifications of creepage distances and clearances for
electronic circuits connected between live conductors (phases and neutral)
and/or between live conductors and the earth circuit when the contacts are

in the closed position . 87
9.31.1 PRCDs shall not create fire and/or shock hazards under abnormal
conditions likely to occur in service. . 87
9.31.2 When PRCDs are exposed to abnormal conditions, no part shall reach
temperatures likely to cause danger of fire to the surroundings of the
PRCDs and no live parts shall become accessible. . 87
9.31.3 Unless otherwise specified, the tests are made on PRCDs while they
are mounted, connected and loaded as specified in 9.8. . 88
9.32 Requirements for capacitors and specific resistors and inductors used in
electronic circuits connected between live conductors (phases and neutral)
and/or between live conductors and the earth circuit when the contacts are
in the closed position . 90
9.32.1 Capacitors . 90
9.32.2 Resistors and inductors . 90
9.33 Verification of the behaviour of the PRCD under temporary over voltage
(TOV) conditions . 90
9.33.1 General . 90
9.33.2 Test for all PRCDs . 90
9.33.3 Verification after the tests . 91
Annex A (normative) Test sequences and number of samples to be submitted for
verification of conformity to this document . 119
A.1 Verification of conformity . 119
A.2 Test sequences . 119
A.3 Number of samples to be submitted for full test procedure . 121

A.4 Number of samples to be submitted for simplified test procedures in case of
submitting simultaneously a range of PRCDs of the same fundamental
design . 121
Annex B (normative) Routine tests . 126
B.1 General . 126
B.2 Tripping test . 126
B.3 Dielectric strength test . 126
B.4 Performance of the test device . 126
B.5 Stray wire test . 126
B.6 Correct continuity test . 127
Annex C (normative) Determination of clearances and creepage distances . 128
C.1 General . 128
C.2 Orientation and location of a creepage distance . 128
C.3 Creepage distances where more than one material is used . 128
C.4 Creepage distances split by floating conductive part . 128
C.5 Measurement of creepage distances and clearances . 128
Annex D (normative) List of tests, additional test sequences and numbers of samples
for verification of compliance of PRCDs with the requirements of electromagnetic
compatibility (EMC) . 132
D.1 General . 132
D.2 EMC tests already included in the product standard . 132
D.3 Additional tests of IEC 61543 to be applied . 132
Annex E (informative) Application of PRCD according to 4.8.2 (PRCD-S) . 134
E.1 Explanation of switched protective conductor function and application . 134
E.2 Examples of incorrect supply wiring . 135
Annex F (informative) Examples of terminal designs . 138
Annex G (informative) Correspondence between ISO and AWG copper conductors . 141
Annex H (informative) Methods for determination of short-circuit power-factor . 142
Bibliography . 143

Figure 1 – Examples of types of connection classified according to 4.1 . 92
Figure 2 – Standard test wire 1,0 mm . 93
Figure 3 – Gauge for checking non-accessibility of live parts through shutters and of
live parts of socket-outlets with increased protection. 94
Figure 4 – Test circuit for the verification of the correct operation of PRCDs, in the

case of residual pulsating direct currents . 95
Figure 5 – Test circuit for the verification of the correct operation of PRCDs, in the
case of residual pulsating direct currents superimposed by a smooth direct current . 96
Figure 6 – Verification of behaviour in case of external fault current in the protective
conductor . 97
Figure 7 – Test circuit for the verification of the rated making and breaking capacity

and of the coordination . 98
Figure 8 – Tumbling barrel . 99
Figure 9 – Arrangement for compression test . 99
Figure 10 – Ball-pressure test apparatus. 100
Figure 11 – Arrangement and dimensions of the electrodes for the tracking test . 100
Figure 12 – Apparatus for testing the cord retention . 101
Figure 13 – Apparatus for flexing test . 102

– 8 – IEC 61540:2023 © IEC 2023
Figure 14 – Arrangement for mechanical strength test on PRCDs provided with cords
(9.12.6) . 103
Figure 15 – Test apparatus for the verification of the minimum I t and I values to be
p
withstood by the PRCD (9.11.2.1 a)) . 104
Figure 16 – Stabilizing period for reliability test (9.21.1.4) . 105
Figure 17 – Reliability test cycle (9.21.1.4) . 106
Figure 18 – Example for test circuit for verification of ageing of electronic components
(9.22) . 107
Figure 19 – Current ring wave 0,5 µs/100 kHz . 107
Figure 20 – Example of test circuit for the verification of resistance to unwanted
tripping . 108
Figure 21 – Minimum creepage distances and clearances as a function of peak value
of voltage . 109
Figure 22 – Minimum creepage distances and clearances as a function of peak value
of operating voltage . 110
Figure 23 – Test cycle for low temperature test (9.9.4). 111
Figure 24 – Test circuit for the verification of operating characteristic (9.9), endurance
test (9.10), trip-free mechanism (9.15) and behaviour in case of failure of line voltage
(9.17) . 112
Figure 25 – Test circuit for the verification of PRCD when plugged into incompatible
supply systems (9.9.5.4) . 113
Figure 26 – Verification of correct operation for hazardous live PE (see Table 15) . 114
Figure 27 – Verification of open neutral for LNSE types, and open line for LLSE types . 115
Figure 28 – Verification of a standing current in the protective conductor in normal
service (9.9.8) . 116
Figure 29 – Verification of open protective conductor (see 9.9.5.5) . 117
Figure 30 – Standard test finger . 118
Figure C.1 – Examples of methods of measuring creepage distances and clearances . 131
Figure E.1 – Examples of incorrect supply wirings for LLSE types. 136
Figure E.2 – Examples of incorrect supply wirings for LNSE types . 137
Figure F.1 – Examples of pillar terminals . 138
Figure F.2 – Examples of screw terminals and stud terminals . 139
Figure F.3 – Examples of saddle terminals. 140
Figure F.4 – Examples of lug terminals . 140

Table 1 – Standard values of rated current and corresponding preferred values of rated
operational voltages . 23
Table 2 – Standard values of maximum break time for AC residual currents . 24
Table 3 – Marking or information item . 25
Table 4 – Standard conditions for operation in service . 27
Table 5 – Minimum cross-sectional area of flexible cable or cord suitable for non-
rewireable plugs and non-rewireable socket-outlets of PRCDs . 33
Table 6 – Clearances and creepage distances . 36
Table 7 – Connectable cross-sections of copper conductors for screw-type terminals . 38
Table 8 – Degree of protection of PRCD parts . 41
Table 9 – Temperature-rise values . 42

Table 10 – List of type tests . 47
Table 11 – Cross-sectional area for test conductors . 48
Table 12 – Screw thread diameters and applied torques . 49
Table 13 – Conductor composition . 51
Table 14 – Test voltage for verification of impulse withstand voltage . 57
Table 15 – Supply failure and hazardous live protective conductor (PE) connections for
test with reference to correct supply connections for LNSE and LLSE types . 62
Table 16 – Tests to verify the behaviour of PRCDs under overcurrent conditions . 67
Table 17 – List of tests of resistance to mechanical shock and impact . 73
Table 18 – Torque applied to the spanner for the test of 9.12.3. 74
Table 19 – Tripping current ranges for PRCDs in case of pulsating DC current . 80
Table 20 – Make-up of cables suitable for the retention test of rewireable PRCDs . 85
Table 21 – Maximum permissible temperatures under abnormal conditions. 89
Table A.1 – Test
...