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BS 2771-1:1986



A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.

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A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.

Electrical equipment of industrial machines Specification for general requirements

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Withdrawn date




Published date


Brief history
Technical text
Preface of IEC publication 204-1 (1981)
1. General
1.1 Scope
1.2 Object
1.3 Additional user requirements
1.4 General operating, transportation and storage
1.4.1 Ambient air temperature
1.4.2 Altitude
1.4.3 Atmospheric conditions
1.4.4 Installation and operating conditions
1.4.5 Transportation and storage
2. Definitions
2.1 Electronic equipment
2.2 Controlgear assembly
2.3 Enclosure
2.4 Duct
2.5 Conduit
2.6 Live part
2.7 Exposed conductive part
2.8 Protective conductor
2.9 Protective circuit
2.10 Power circuit
2.11 Control circuit
2.12 Signalling circuit
2.13 Component
2.14 Switching device
2.15 Control device
2.16 Actuator
2.17 Marking
2.18 Item designation
2.19 Servicing level
2.20 Instructed persons
2.21 Skilled persons
3. Warning signs, marking, item designation and
     technical documentation
3.1 Warning signs, marking and item designation
3.1.1 Warning signs on enclosures
3.1.2 Marking of controlgear assemblies
3.1.3 Marking of control devices
3.1.4 Marking of replaceable components
3.1.5 Item designation of components, devices,
         terminals, cables and conductors
3.1.6 Functional identification of actuators
3.2 Technical documentation
3.2.1 General
3.2.2 List of the different types of documents
3.2.3 Requirements applicable to all documents
3.2.4 Requirements applicable to particular documents
4. General requirements
4.1 Components and devices
4.2 Supply
4.3 Connection to the supply network
5. Protective measures
5.1 Protection against electric shock
5.1.1 Protection against electric shock in normal
5.1.2 Protection against electric shock in case of a
5.1.3 Protection against electric shock both in normal
        service and in case of a fault, protection by
        "machine extra-low voltage (MELV)"
5.1.4 Residual voltages
5.2 Short-circuit protection
5.2.1 General protection
5.2.2 Protection of circuits and branches
5.2.3 Rating and setting of short-circuit protective
5.2.4 Conductors in front of the devices protecting
5.3 Overload protection
5.4 Protection against automatic re-start after supply
      interruption and restoration
5.5 Voltage drop protection
5.6 Emergency stopping and supply disconnecting device
5.7 Protection in case of failure
5.8 Interferences
6. Control and signalling circuits
6.1 Control and signalling circuit supplies and
6.1.1 Use of transformers
6.1.2 Direct connection to the supply
6.1.3 Several transformers
6.1.4 Overcurrent protection
6.2 Control circuit
6.2.1 Preferred values of the control voltages
6.2.2 Protection against unintended operation by earth
6.2.3 Connection of coils and contacts and input/
        output units
6.2.4 Protective interlocks
6.2.5 START and STOP functions
6.2.6 Cycle start
6.2.7 Emergency stop
6.2.8 Automatic operation - manual operation
6.2.9 Control of sequence in automatic operation
6.3 Signalling circuit
7. Mechanical design, arrangement of electrical devices,
7.1 Requirements applicable to the whole electrical
7.1.1 Arrangement of electrical devices
7.1.2 Accessibility
7.1.3 Clearances and creepage distances
7.2 Controlgear assemblies
7.2.1 Degrees of protection
7.2.2 Openings
7.2.3 Doors
7.2.4 Arrangement of electrical devices
7.2.5 Non-electric parts and devices
7.2.6 Mounting and handling of controlgear assemblies
8. Control devices
8.1 General
8.1.1 Location and mounting
8.1.2 Protection
8.1.3 Plug-in control devices
8.1.4 Position sensors (including proximity sensors)
8.1.5 Electro-magnets
8.1.6 Pressure and temperature sensors
8.2 Hand-operated control switches and indicator lights
8.2.1 Accessibility of switches
8.2.2 Protection
8.2.3 Push-buttons
8.2.4 Indicator lights (signalling lamps)
8.2.5 Illuminated push-buttons
9. Cables and conductors
9.1 Types of conductors and cables
9.2 Insulation of cables
9.3 Cross-section of conductors
9.3.1 Current-carrying capacity
9.3.2 Voltage drop
9.3.3 Minimum cross-sections of copper conductors
10. Wiring
10.1 General
10.1.1 Connections
10.1.2 Cable runs
10.1.3 Connections to movable parts
10.1.4 Conductors of different circuits
10.1.5 Cable lugs
10.1.6 Terminals and connection boxes
10.2 Identification of conductors
10.2.1 Identification of the protective conductor (PE)
         and of the neutral conductor (N)
10.2.2 Identification of other conductors
10.3 Wiring inside enclosures
10.3.1 Internal ducts
10.3.2 Interconnection terminals and plug-and-socket
10.3.3 Test points
10.4 Wiring outside enclosures
10.4.1 External ducts
10.4.2 Connection to moving elements of the machine
10.4.3 Interconnection of devices on the machine
10.4.4 Plug and socket connections
10.4.5 Dismantling for shipment
10.4.6 Spare conductors
11. Electric motors
11.1 General requirements
11.2 Dimensions
11.3 Characteristics
11.4 Type of enclosure
11.5 Mechanical vibration
11.6 Method of starting
11.7 Mounting
11.8 Nameplates
12. Connection to accessories and local lighting
12.1 Connection to accessories
12.2 Local lighting of the machine
13. Testing
13.1 Insulation tests
13.2 Voltage test
13.3 Continuity of the protective circuit
13.4 Operating tests
13.4.1 Routine test without load on the machine
13.4.2 Operating type test with the loaded machine
14. Inquiry form
Appendix A (normative) - Inquiry form for the electrical
                         equipment of industrial machines
Appendix B (normative) - Current-carrying capacity and
                         short-circuit protection of
                         cables insulated with polyvinyl
                         chloride in the electrical
                         equipment of industrial machines
Appendix C (normative) - Comparison of the conductor
                         cross-sectional areas
Appendix D (informative) - Item designation of the
                           electrical equipment of
                           industrial machines
Appendix E (informative) - Examples of drawings, diagrams,
                           tables and instructions
Appendix G (informative) - Original IEC text of Scope of
                           IEC 204-1 (1981)

Applies to the electrical and electronic equipment of machines not portable by hand when working, used in industrial production and operated from a supply up to 1000 V a.c. Gives requirements to ensure safety of personnel and property, uninterrupted productivity, long life of the equipment, ease and economy of maintenance.

Replaces CP 1015: 1967
British Standards Institution

Standards Relationship
IEC 60204-1:2016 Identical
NFC 79 130 : 1985 Identical
VDE 0113-1 : 2007 COR 1 2010 Identical
EN 60204-1 : 2006 COR 2010 Identical

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