NF EN 50178 : 1999

1 Scope
2 Normative references
3 Definitions
4 Requirements
    4.1 Normal function
    4.2 Damage to persons or material
    4.3 EE connected to unearthed supply mains under
          conditions of earth fault
    4.4 Earthing requirements (grounding, earthing
          and screening)
    4.5 Wires and cables for interconnection
    4.6 Fuses in neutral and protective conductors
5 Safety requirements
    5.1 General requirements
    5.2 Requirements for EE with regard to protection
          against electric shock
    5.3 Requirements for EEs in installations with regard
          to protection against electric shock
6 Environmental requirements and conditions
    6.1 Climatic conditions
    6.2 Mechanical requirements (general)
    6.3 Electrical and electromagnetic requirements
7 Requirements for electronic equipment
    7.1 Design and construction
    7.2 Marking, identification, documentation
8 Requirements for the assembly of EE(s) in power
    installations
    8.1 General
    8.2 Fitting tolerances after assembly
    8.3 Supply mains
9 Testing
    9.1 General
    9.2 Compliance with this European Standard
    9.3 Overview of tests
    9.4 Performance of the tests
Annex A (informative) Additional information
    A.2 Bibliography
    A.4 Requirements for entire system
    A.5 Safety requirements
    A.6 Environmental requirements and conditions
    A.7 Requirements for electronic equipment
    A.8 Requirements for the assembly of EE(s) in power
          installations
    A.9 Testing
Annex B (informative) Tables and figures
Figures
1 Arrangement of fuses in sub-assemblies and in
    installations
2 Functional summary of protective measures against
    electric shock
3 Examples for protection against direct contact
4 Flow chart leading to requirements when using EE(s)
    behind an RCD
5 Typical waveform for case a)a.c. voltage
6 Typical waveform for case b)d.c. voltage
7 Typical waveform for case c)pulsating voltage
8 Determination of insulation within a circuit
9 Determination of insulation between live parts and
    accessible surfaces
10 Determination of insulation between circuits and
    environment and of insulation between circuits
11 Determination of functional insulation
12 Determination of basic insulation
13 Determination of double or reinforced insulation
14 Protective separation (with the respective subclauses
    in parentheses)
15 Clearances and creepage distances for protective
    separation
16 Voltage test procedure
A.1 Examples for protection in the case of direct contact
A.2 Fault-current in connections with semiconductor devices
A.3 Planning example for application of RCD Type B
A.4 Examples of sub-divided insulation against accessible
    surfaces of EE
A.5 Examples for the insulation of control elements
A.6 Examples for the design of clearances (continued)
A.7 Correlation between humidity and temperature of the air
A.8 Periodical momentary dips of a.c. mains voltage caused
    by convertors
A.9 Insulation displacement connection with flat cable
A.10Test set-up for EE grounded via a dedicated earthing
    connection
A.11Test set-up for EE grounded via the power cord
A.12Application of the test voltage to a single port and
    to grouping of ports
Tables
1 Summary of the limits of the decisive voltage UM
2 Definitions of pollution degrees
3 Clearances between mains-circuits and their environment
4 Clearances between non-mains-circuits and their
    environment
5 Clearances within a circuit
6 Minimum creepage distances
7 Climatic conditions
8 Heating of accessible parts
9 General test conditions
10 Overview of tests
11 Dry heat test
12 Damp heat test
13 Topple test
14 Vibration test
15 Non-accessibility test
16 Impulse voltage test
17 Impulse test voltage
18 A.c. or d.c. insulation test voltage
19 Partial discharge test
20 Minimum value of insulation resistance
21 Short-circuit withstand capability
A.1 Values of accessible capacitance and charging voltage
    (threshold of pain)
A.2 Maximum concentration of corrosive gases

Applicable to the use of electronic equipment in power installations requiring a uniform technical level of safety and reliability. Specifies the minimum requirements for the design and manufacture of EE, to protect against electric shock, for testing and integrating into systems for power installations.