- measurement of the fault loop impedance (Zs).

Exception: Where the calculations of the fault loop impedance or of the resistance of the protective conductors are available and when the arrangement of the installations permits the verification of the length and cross-sectional area of the conductors, verification of the continuity of the protective conductors may replace the measurement.

A.4.2 Measurement of the fault loop impedance

Measurement of the fault loop impedance shall be performed using measuring equipment that complies with IEC 61557-3. The information about the accuracy of the measuring results, and the procedures to be followed given in the documentation of the measuring equipment shall be considered.

Measurement shall be performed when the machine is connected to a supply having the same frequency as the nominal frequency of the supply at the intended installation.

NOTE Figure A.1 illustrates a typical arrangement for measuring the fault loop impedance on a machine. If it is not practicable for the motor to be connected during the test, the two phase conductors not used in the test can be opened, for example, by removing fuses.

The measured value of the fault loop impedance shall comply with A.2.

A.4.3 Consideration of the difference between the measured value of resistance of

the conductors and the actual value under fault conditions

NOTE As the measurements are made at ambient temperature, with low currents, it is necessary to take into account the increase of resistance of the conductors with the increase of temperature under fault conditions, to verify the compliance of the measured value of the fault loop impedance with the requirements of Clause A.2.

The increase of resistance of the conductors with the increase of temperature due to the fault current is taken into account in the following equation:

° 7a

where Zs(m) is the measured value of Zs.

Where the measured value of the fault loop impedance exceeds 2t/0/3Za , a more precise assessment can be made in accordance with the procedure described in C. of IEC 60364-6:2006.

Figure А.1 - Typical arrangement for fault loop impedance measurement

Annex В

Enquiry form for the electrical equipment of machines

It is recommended that the following information be provided by the intended user of the equipment. It can facilitate an agreement between the user and supplier on basic conditions and additional user requirements to enable proper design, application and utilization of the electrical equipment of the machine (see 4.1).

Name of manufacturer/supplier

Name of end user

Tender/order number


Type of machine

Serial number

1. Special conditions (see Clause 1)

a) Is the machine to be used in the open air?



b) Will the machine use, process or produce explosive or flammable material?


If yes, specification

c) Is the machine for use in potentially explosive or flammable atmospheres?


If yes, specification

d) Can the machine present special hazards when producing or consuming certain materials?


If yes, specification

e) Is the machine for use in mines?



2. Electrical supplies and related conditions (see


a) Anticipated voltage fluctuations (if more than ±10 %)

b) Anticipated frequency fluctuations (if more than ±2 %)


Short time

c) Indicate possible future changes in electrical equipment that will require an increase in the electrical supply requirements

d) Specify voltage interruptions in supply if longer than specified in Clause 4 where electrical equipment has to maintain operation under such conditions

3. Physical environment and operating conditions (see 4.4)

a) Electromagnetic environment (see 4.4.2)

Residential, commercial or light industrial environment

Industrial environment

Special conditions or requirements

b) Ambient temperature range

c) Humidity range

d) Altitude

e) Special environmental conditions (for example corrosive atmospheres, dust, wet environments)

f) Radiation

g) Vibration, shock

h) Special installation and operation requirements (for example flame-retardant cables and conductors)

i) Transportation and storage (for example, temperatures outside the range specified in Subclause 4.5)

4. Incoming electrical supplies

Specify for each source of supply:

a) Nominal voltage (V)



If a.c., number of phases


Prospective short-circuit current at the point of supply to the machine (kA r.m.s.) (see also item 2)

b) Type of power supply earthing (see IEC 60364-1)

TN (system with one point directly earthed, with a protective conductor (PE) directly connected to that point); specify if the earthed point is the neutral point (centre of the star) or another point)

TT (system with one point directly earthed but the protective conductor (PE) of the machine not connected to that earth point of the system)

IT (system that is not directly earthed)

c) Is the electrical equipment to be connected to a neutral (N) supply conductor? (See 5.1)



d) Supply disconnecting device

Is disconnection of the neutral (N) conductor required?



Is a removable link for disconnecting the neutral (N) required?



Type of supply disconnecting device to be provided

5. Protection against electric shock (see Clause 6)

a) For which of the following classes of persons is access to the interior of enclosures required during normal operation of the equipment?

Electrically skilled persons

Electrically instructed persons

b) Are locks with removable keys to be provided for securing the doors or covers? (see 6.2.2)



6. Protection of equipment (see Clause 7)

a) Will the user or the supplier provide the overcurrent protection of the supply conductors? (see 7.2.2)

Type and rating of overcurrent protective devices

b) Largest (kW) three-phase a.c. motor that may be started direct-on-line

c) May the number of motor overload detection devices be reduced? (see 7.3)



7. Operation

For cableless control systems, specify the time delay before automatic machine shutdown is initiated in the absence of a valid signal.

8. Operator interface and machine-mounted control devices (see Clause 10)

Special colour preferences (for example to align with existing machinery):




9. Controlgear

Degree of protection of enclosures (see Subclause 11.3) or special conditions:

10. Wiring practices (see Clause 13)

Is there a specific method of identification to be used for the conductors? (see 13.2.1)




11. Accessories and lighting (see Clause 15)

a) Is a particular type of socket-outlet required?



If yes, which type?

b) Are the socket-outlets for maintenance to be provided with additional protection by the use of Residual Current protective Devices (RCD)?



c) Where the machine is equipped with local lighting:

Highest permissible voltage (V)

If lighting circuit voltage is not obtained directly from the power supply, state preferred voltage

12. Marking, warnings and reference designations (see Clause 16)

a) Functional identification (see 16.3)


b) Inscriptions/special markings

On electrical equipment?

In which language?

c) Mark of certification



If yes, which one?

13. Technical documentation (see Clause17)

a) Technical documentation (see 17.1)

On what media?

In which language?

b) Size, location and purpose of ducts, open cable trays or cable supports to be provided by the user (see 17.5)

c) Indicate if special limitations on the size or weight affect the transport of a particular machine or controlgear assemblies to the installation site:

Maximum dimensions

Maximum weight

d) In the case of specially built machines, is a certificate of operating tests with the loaded machine to be supplied?



e) In the case of other machines, is a certificate of operating type tests on a loaded prototype machine to be supplied?



Annex С

Examples of machines covered by this part of IEC 60204

The following list shows examples of machines whose electrical equipment should conform to this part of IEC 60204. The list is not intended to be exhaustive but is consistent with the definition of machinery (3.35). This part of IEC 60204 need not be applied to machines that are household and similar domestic appliances within the scope of the IEC 60335 series of standards.

Metalworking machinery

Food machinery

  • metal cutting machines

  • metal forming machines

  • dough breaks

  • mixing machines

  • pie and tart machines

  • meat processing machines

Plastics and rubber machinery

Printing, paper and board machinery

  • injection moulding machines

  • extrusion machines

  • printing machines

  • finishing machines, guillotines,

  • blow moulding machines

  • thermoset moulding machines

  • size reduction machines


  • reeling and slitting machines

  • folder box gluing machines

  • paper and board making machines

Wood machinery

Inspecting/testing machinery

  • woodworking machines

  • laminating machines

  • sawmill machines

  • co-ordinate measuring machines

  • in-process gauging machines

Assembly machines


Material handling machines

Packaging machinery

• robots

• palletizers/depalletizers


  • transfer machines

  • storage and retrieval machines

wrapping and shrink-wrapping machines

Textile machines

Laundry machines

Refrigeration and air-conditioning machines

Heating and ventilating machines

Leather/imStation leather goods and footwear machinery

  • cutting and punching machines

  • roughing, scouring, buffing, trimming and brushing machines

  • footwear moulding machines

  • lasting machines

Hoisting machinery (see

IEC 60204-32)

  • cranes

  • hoists

Machinery for transportation of


  • escalators

  • ropeways for transportation of persons, for example chairlifts, ski lifts

  • passenger lifts

Power-operated doors

Leisure machinery

  • fairground rides


Agriculture and forestry machines

Construction and building materials machinery

  • tunnelling machines

  • concrete batching machines

  • brick-making machines

  • stone, ceramic and glass-making machines

Transportable machinery

  • wood working machines

  • metal working machines

Mobile machinery

  • lifting platforms

  • fork lift trucks

  • construction machines

Machines for hot metal processing

Tanning machinery

  • multi-roller machines

  • bandknife machines

  • hydraulic tanning machines

Mining and quarrying machine

sAnnex D

Current-carrying capacity and overcurrent protection
of conductors and cables in the electrical equipment of machines

The purpose of this Annex is to provide additional information on the selection of conductor sizes where the conditions given for Table 6 (see Clause 12) have to be modified (see notes to Table 6).

D.1 General operating conditions

D.1.1 Ambient air temperature

The current carrying capacity for PVC insulated conductors given in Table 6 is related to an ambient air temperature of +40 °С. For other ambient air temperatures, the correction factors are given in Table D.1.

The correction factors for rubber insulated cables are given by the manufacturer.

Table D.1 - Correction factors

Ambient air temperature °С

Correction factor















NOTE The correction factors are derived from IEC 60364-5-52.

The maximum temperature under normal conditions for PVC 70 °С.

D.1.2 Methods of installation

In machines, the methods of conductor and cable installation between enclosures and individual items of the equipment shown in Figure D.1 are assumed to be typical (the letters used are in accordance with IEC 60364-5-52: 2001):