Iranian Classification Society Rules

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Section 21 Electrical Equipment and Cables


2101. General


1. Application

The requirements in this Section apply to tests and inspection for the type of electrical equipment and cables in accordance with the requirements in Pt 6, Ch 1, 109. of the Rules.

2. Items subject to the tests

Electrical equipment and cables subject to the type test are to

3.21.1.

be as the requirements in Table


Table 3.21.1 Electrical equipment and cables subject to the type test


Kinds

Electrical equipment and cables subject to the type test


Fuses

Cartridge type fuses (renewable and non-renewable) and plug type fuses used for the pro- tection of the low-voltage electric circuits


Circuit breakers

Low-voltage breakers, air circuit breakers and molded case circuit breakers (including molded case circuit breakers with fuses and molded case circuit breakers used for the protection of induction motors simultaneously. Hereinafter, these are referred to as molded case circuit breakers unless otherwise specified.), used for protection of the electric circuits

Electromagnetic contactors and protective relays


Electromagnetic contactors and protective relays used for motors and other loads connected to the low-voltage electric circuits


Explosion-protected electrical equipment

Electrical equipment of the flameproof type, intrinsically safe type, increased safety type and pressurized protected type (limited to sealed type) used in the spaces on board flammable or explosive gas or vapour (hereinafter referred to as explosive gas) exists or may exist in the atmosphere.


Cables

(1) Cables used for power circuits, lighting circuits, supply and distribution circuits of in- terior-communication, control circuits, etc.

(2) Flexible cords used for power supply and distribution circuits.

(3) 150 V multi-core PVC insulated cables for electronic equipment.


Other electrical equipment

The following electrical equipment produced by mass production method at the same manu- facturing plant which obtained the Approval of Quality Assurance System specified in Ch 5 of the Guidance

- Generators, electrical motor, control gears for electrical motor, power and lighting trans- formers, switchboards, axial flow fan driven by motor built in casing and semi-conductor rectifiers


2102. Data to be submitted

Data are to be submitted to the Society in accordance with the requirements in 102. and the fol- lowing drawings and documents are to be included for explosion-protected electrical equipment. Items (4), (5) and (6) are, however, required for intrinsically safe type electrical equipment only.

(1) Drawings of detailed sectional assembly and arrangement of components

(2) List of electrical parts and materials

(3) Functional descriptions of explosion-protected constructions

(4) Electric circuit diagrams

(5) Sectional assembly drawings of transformers with earthed screens and component parts (relays, photocouplers, etc.) used for maintenance of intrinsic safety

(6) Construction drawings and circuit diagrams of safety barriers


Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 127

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2103. Type tests

Type tests are to be carried out in accordance with the requirements in 2104. to 2109. for each product. In case where the Society deemed necessary, however, additional tests and/or an increase in the number of test samples may be required. For products specified in foreign standards, test items and the number of test samples will be decided at each case in accordance with the contents of the standards.


2104. Test method of fuses

The details of test are to comply with the recognized code ((KS C) IEC

deemed necessary, the ambient temperature may be modified.


60269 series, etc.). Where


2105. Test method of circuit-breakers

The details of test are to comply with the recognized code ((KS C) IEC 60947-1, (KS C) IEC 60947- 2, (KS C) IEC 62271-100 and KS C 8321, etc.). Where deemed necessary, the ambient temperature may be modified.


2106. Test method of electromagnetic contactors

The details of test are to comply with the recognized code ((KS C) IEC 60947-1, IEC 60947-4

and KS C 4504, etc.). Where deemed necessary, the ambient temperature may be modified.


2107. Test method of explosion-protected electric equipment


1. Test items and number of samples

The test items marked "O" in Table 3.21.2 are to be conducted plosion-protection type.


on one test sample per each ex-


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Table 3.21.2 Test Items of Explosion Protected Equipment


Types of explosion

protection Test items


Flameproof type


Intrinsically safe type


Increased safety type


Pressurized protected type

Construction inspection

Temperature rise test

(note)

Mechanical strength test

Explosion test

Pressurization test

Spark ignition test

Other test deemed necessary

NOTE:

Temperature rise test in the locking test for motors is to be included. REMARKS:

1. The mechanical strength test is to apply to movable apparatus, inspection windows, lighting fittings, port- able lamps with batteries, plug-sockets and flexible fittings.

2. Other tests deemed necessary are to include thermal shock (heat resistance) test, water-tight test, air-tight test, function test of protective devices, etc.


2. Test methods

Test methods are to comply with the requirements given in


Table 3.21.3 or KS C IEC 60079 series.


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Internal volume (cm )


Less than 2

2 over 100 incl.


over 100

Internal pressure (MPa)

Necessary for fabrication


0.8 or over


1.0 or over

Ignition group

G1

G2

G3

G4

G5

Limit of temperature rise


310


190


110


60


30

Table 3.21.3 Test methods and acceptance criteria for explosion-protected equipment


Types

Test item

Test method

Acceptance criteria


Flameproof type electric equipment


(A)

Explosion withstand test

(a) The enclosure is filled with the flammable mixture which will produce the explosion pressure specified in Table belows ac- cording to the internal volume and tested by repeatedly ignit- ing and exploding the mixture 10 times.


(b) The gaps of the enclosure may be sealed temporally to per- form the test.

The enclosure is not to be damaged or obstructively deformed


(B)

Flame propagation test

(a) The flammable mixture having flame propagation characteristic which can prove the safe guardness against each gas involved in each explosion class is filled inside and outside the enclo- sure and is ignited inside the enclosure and exploded re- peatedly 15 times. In case where the pressure specified in

(A) of this Table is available in this test, the explosion withstand test above may be included in this test.

(b) The position considered as the flame propagation is most ready to occur in the enclosure is to be selected for the posi- tion of ignition.

The flame propagation is not to occur


(C)

Temperature rise test

To pass the rated current to the equipment (as for lighting fixtures, by turning or the maximum appli- cable lamp with the rated current) until the temper- ature at each part is saturated.

The temperature rise of the external parts of the enclosure is not to exceed the limit specified in Table below

(Standard ambient temperature 50°C)


(D)

Mechanical strength test

(a) The steel ball falling test of light transparent plate, light trans- parent window and inspection window ;

The transparent plate (except for the cylindrical glass globes

for fluorescent lamp) is dropped by the steel ball specified in Table below on the weakest part considered of the plate un- der the condition being fitted on to the equipment or equiv- alent condition.


This test is, in principle, to be carried out on three test speci- mens and each of them is required to pass the test. For the indicating lamps, in case where the steel ball can not strike the glass cover through the openings of the guard, the test is to be conducted by dropping a steel ball sufficiently small to directly strike.

Not to cause any damage and cracks which may im- pair the flame-proofness

(b) The strength test of cylindrical glass globe for fluorescent lamp

The cylindrical glass globe is dropped by a steel ball of 50 g (diameter approximately 23 mm from a height of 100 cm on the weakest part considered of the cylindrical glass globe un- der the condition being fitted on to the equipment and held horizontally. And, the cylindrical glass globe is applied the in- ternal hydrostatic pressure of not less than 2.0 MPa for 15 seconds. This test is, in principle, to be carried out on three test specimens and each of them is required to pass the test.


The cylindrical glass globe is not to be damaged and is to withstand the internal hydrostatic pressure.


Transparent material

Mass of steel ball (g)

Dropping height (cm)

Glove

95

(diameter approximately 28.5 mm)

100

Cylindric glass

50

(diameter approximately 23.0 mm)

100

Sheet glass

200

(diameter approximately 36.5 mm)

200

Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 129

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Table 3.21.3 Test methods and acceptance criteria for explosion-protected equipment (continued)


Types

Test item

Test method

Acceptance criteria


Flameproof type electric equipment

Drop test for portable type apparatus


The portable type apparatus is dropped three times on to the steel plate of 6 mm in thickness from a height of 1.5 m by changing the position to collide.


Not to be impairer the flame-proofness


Thermal shock test

The electric apparatus with light transparent windows or in- spection windows is poured by water at a temperature of 10°C lower than the room temperature (minimum 5°C) onto the electric apparatus after the electric apparatus has been operated until the temperature of the light transparent material is saturated. This test is, in principle, to be carried out on three test specimens and each of them is required to pass the test. The test, however, may be omitted in case where the light transparent material can be considered to have a little temperature rise and to pass the thermal shock test apparently judging from test results in the past.

Not to cause cracks of damage on the light trans- parent material


Intrinsically safe type electrical equipment


Temperature rise test

The temperature rise of the parts in contact with explosive gas of the intrinsically safe type electrical equipment is measured under the normal operational condition and under the maximum current or voltage which can be generated in time of fault. The test, however, may be omitted in case where the temperature rise of the apparatus can be considered not to exceed the limit appa- rently judging from the test results in the past.

not to exceed the limit specified in the temper- ature rise test of flame- proof type electric equip- ment


Spark ignition test

The intrinsically safe type electric equipment, at all parts of in- trinsically safe circuit, is to be carried out the spark ignition test specified in the following (a) to (e) by using the lEC type spark ignition testing apparatus to verify that any sparks in normal op- eration and abnormal condition (short circuit, earth fault, breakage of cable, etc.) do not ignite explosive gas or vapour specified in Table 3.21.1. This test apply to the first product and may be omitted for the subsequent products of the same manufacturer in case where the voltage or the current of the circuit specified in the following (a) does not exceed that of the spark ignition test circuit by 20 %.

(a) The spark ignition test is to be conducted in way of the cir-

cuit where the maximum voltage or current can be generated in normal operation and abnormal condition. For the safety barrier, however, the test is to be conducted at the connect- ing terminals of the intrinsically safe circuit side by applying the intrinsically safe rated voltage to the non-intrinsically safe circuit side. The intrinsically safe rated voltage means the voltage generated in the non-intrinsically safe circuit in nor- mal operation and abnormal condition and the maximum voltage in the non-intrinsically safe circuit side of the safety barrier at which the intrinsical safety can be ensured.

(b) The value of the testing voltage or the testing current is to be the value obtained from multiplying the maximum voltage or current in normal operation and abnormal condition in the circuit to be intrinsical safe by the safety factor. The safety factor is, in principle, to be 2.

(c) The number of revolutions of the testing equipment is to be more than 200 times per each pole for the d.c. circuit and more than 1,000 times for the a.c. circuit.

(d) The test gas is, in principle, to comply with either of the following:

(i) 1 Class: Propane-air mixture gas (5.25 ± 0.25 vol %)

(ii) 2 Class: Ethylene-air mixture gas (7.8 ± 0.5 vol %)

(iii) 3 Class: Hydrogen-air mixture gas (21 ± 2 vol %)

The intrinsically safe type electric equipment, at all parts of intrinsically safe circuit, is to pass the spark ignition test


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Table 3.21.3 Test methods and acceptance criteria for explosion-protected equipment (continued)


Types

Test item

Test method

Acceptance criteria


Intrinsically safe type electrical equipment


Spark ignition test


(e) The sensitivity of the spark ignition testing equipment before and after the test is to be adjusted so that the maximum igni- tion current becomes approximately 65 mA for ethylene-air mixture gas and approximately 30 mA for hydrogen-air mix- ture gas when the sparks are produced in the gas by inserting the testing equipment into the electric circuit as shown in Fig

below.


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Drop test for portable type apparatus


The portable type apparatus is dropped onto the steel plate of 6 mm in thickness fixed on the floor from an effective height of

1.5 m. The test is to be carried out three times by changing the positions to collide which are selected as the weakest positions judging from the structural features of the test specimen.

Not to be damaged on the external covers and not to cause damage or deforma- tion in the internal circuit which may impair the in- trinsical safety


Increased safety type electrical equipment


Temperature rise test

The temperature rise of the increased safe type electrical equipment is to comply with the following (a) to (d) by being continuously supplied under the rated voltage, the rat- ed output or capacity.

(a) Temperature rise of electrical equipment against ex- plosive gas

The temperature rise of the all parts which may be ex- posed to explosive gas is measured. The temperature rise of insulating windings and bulb socket is to comply with the requirements of the following (b) and (c).

(b) Temperature rise of insulating windings The temperature rise of the insulating windings used for the electric equipment is to be 15°C lower than the value specified in Pt 6, Ch 1, 204. of the Rules. The thermometer method may be used only when the resistance method is hardly applied.

(c) Temperature rise of bulb socket

The temperature rise of the rim and the soldered part of the bulb is not to exceed 145°C.

(d) Temperature rise of leading part of external cable

The temperature rise of the cable entry points is not to exceed 20°C and that of the branching points of the conductor is not to exceed 30°C.

The temperature rise of the all parts which may be exposed to explosive gas is not to exceed the limit given in Table below.


Thermal shock test

The protective lamp cover of the lighting fitting is poured by a water jet with a diameter of approximately 1 mm and with a tem- perature of approximately 20°C onto the parts having the highest temperature, after applying the rated voltage to the maximum ap- plicable bulb until the temperature rise of the outside surface of the protective lamp cover is saturated.


The protective lamp cover of the lighting fitting is not to be damaged or cracked


Ignition group


G1


G2


G3


G4

Enclosures and their parts


310


190


110


60

Surface of lamps for lighting fittings


350


300


250


150

Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 131

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Electrical apparatus


Mass of steel ball (kg)

Height of fall (m)


Enclosures

Lamp protective cover


Guard

Incandescent lights and mercury lights

1

-

0.7

-

2

2

-

2

Fluorescent lights

1

2

0.7

2

Table 3.21.3 Test methods and acceptance criteria for explosion-protected equipment (continued)


Types

Test item

Test method

Acceptance criteria


Increased safety type electrical equipment


Waterproof test


The electrical equipment is to be tested according to the require- ments of test method for IPX4 specified in (KS C) IEC 60529.

To comply with the re- quirements of waterproof test and is to have the waterproof performance ac- cordingly necessary for the place where the electrical equipment is intended to be installed.


Mechanical strength test of lighting fittings

The lighting fittings are dropped by a steel ball (as the end of object) of 25 mm in diameter and a mass specified in Table be- low at the tip onto the weakest part considered from the height specified in the Table, under the condition being fitted on a fixed table.

Not to be damaged


Pressurized protective type electrical equipment (sealed type only)


Temperature rise test


The temperature rise test is to be carried out in accordance with that of flameproof type electrical equipment.

The temperature rise of the external parts of the enclosure is not to exceed the limit specified in table of the flameproof type electrical equipment.


Internal pressure test

The internal pressure test is to comply with the followings.

(a) Internal pressure maintaining test

Being filled with the protective gas up to the specified value,


(b) Operating test of protective device

The pressure of the protective gas falls below the specified value. The test is, in principle, to be conducted for 5 times.

(a) The internal pressure of the equipment is to be satisfactorily maintained.

(b) the device indicating the pressure fall is to operate satisfactorily.


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2108. Test method of cables


1. The details of test are to comply with the recognized code (KS C) IEC 60092-350, etc. given in

Table 3.21.4. Where deemed necessary, the ambient temperature may be modified.


2. In addition to 1 above, tests for vertical flame spread of vertically bunched cable are to be carried

out in accordance with (KS C) IEC 60332-3-22(vertically-mounted bunched

60332-1(single cables).

vertical insulated cable) or (KS C) IEC


Table 3.21.4 Type test item of cables



No.


Test items


IEC code

1

Visual inspection

2

Conductor resistance test

IEC 60092-350, 5.2.2

3

Voltage test

IEC 60092-350, 5.2.3

4

Insulation resistance

IEC 60092-350, 5.2.4 & 7.2

5

Conductor examination

IEC 60092-350, 6.4

6

Insulation thickness

IEC 60092-350, 6.5 & 8.1

7

Non-metallic sheaths thickness

IEC 60092-350, 6.6 & 8.2

8

External diameter

IEC 60092-350, 6.7

9

Hot-set test for insulations and sheaths

IEC 60092-350, 6.8

10

Increase in a.c. capacitance after immersion in water

IEC 60092-350, 7.3

11

High voltage test for 4 h

IEC 60092-350, 7.4

12

Mutual capacitance (control and instrumentation cables only)

IEC 60092-350, 7.5


13

Inductance to resistance ratio (control and instrumentation cables only)


IEC 60092-350, 7.6

14

Mechanical properties of insulation before and after ageing

IEC 60092-350, 8.3

15

Mechanical properties of sheaths before and after ageing

IEC 60092-350, 8.4

16

Compatibility test

IEC 60092-350, 8.5


17

Loss of mass test on PVC insulation and PVC (ST1 and ST2) sheaths


IEC 60092-350, 8.6


18

Test for the behaviour of PVC insulation and PVC (ST1 and ST2) and SHF1 sheaths at high temperatures (hot pressure test)


IEC 60092-350, 8.7


19

Test for the behaviour of PVC insulation and PVC sheath (ST1 and ST2) and SHF1 and SHF2 sheaths at low temperature


IEC 60092-350, 8.8

20

Special test for low temperature behaviour (when required)

IEC 60092-350, 8.9

21

Test of the metal coating of copper wires

IEC 60092-350, 8.10

22

Galvanizing test

IEC 60092-350, 8.11


23

Test for resistance of PVC insulation and PVC (ST1 and ST2) and SHF1 sheaths to cracking (heat shock test)


IEC 60092-350, 8.12

24

Ozone resistance test for insulation and for sheaths

IEC 60092-350, 8.13

25

Oil immersion test for sheaths

IEC 60092-350, 8.14

26

Mud drilling fluid test (when required)

IEC 60092-350, 8.15

27

Fire tests

IEC 60092-350, 8.16

28

Determination of hardness for HEPR and HF HEPR

IEC 60092-350, 8.17

29

Determination of elastic modules for HEPR and HF HEPR

IEC 60092-350, 8.18

30

Durability of print

IEC 60092-350, 8.19


Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 133

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2109. Other electrical


1. The type tests are frame No. or type

equipment


to be carried out on the electrical equipment random selected one for each from the production line to verity their compliance with the relevant require-

ments of Pt 6, Ch 1 of the Rules.


2. The items of the type tests are, in general, to be in accordance with the requirements given in

Table 3.21.5. In case where the Society specifically deems ber of test samples may be required.

necessary, additional test items or num-


Table 3.21.5 Type test item of other electrical equipment


Electrical equipment

The items of the type tests


Generators

(1) Construction inspection

(2) Running test: Temperature rising test, overload test, over-current test, overspeed test

(3) Characteristics test: Voltage variation test, transient voltage variation test

(4) Insulation resistance test (5) High voltage test

(6) Vibration measurement, noise level measurement

(7) Performance test of air cooler (8) Other tests


Electric motors

(1) Construction inspection

(2) Operational test: Temperature rising test, overload test, over-torque test, commutation test and overspeed test

(3) Characteristics test: Load characteristics test

(4) Insulation resistance test (5) High voltage test

(6) Vibration measurement and hose test (7) Other tests


Controlgears for electric motor

(1) Construction inspection (2) Temperature rising test

(3) Operational test (including circuit inspection)

(4) Insulation resistance test (5) High voltage test

(6) Other tests


Power and lighting transformer

(1) Construction inspection (2) Temperature rising test

(3) Insulation resistance test (4) High voltage test

(5) Induced high voltage test (6) Other tests


Switchboards

(1) Construction inspection (2) Temperature rising test (for main circuits)

(3) Operational test (4) Insulation resistance test

(5) High voltage test (6) Other tests


Axial flow fan driven by motor built in casing

(1) Construction inspection

(2) Combined running tests: Temperature rising test, air flow rate and static air pressure meas- urements, shaft power measurements

(3) Insulation resistance test (4) High voltage test

(5) Vibration measurement, noise level measurement

(6) Other tests


Semi-conductor rectifiers

(1) Construction inspection (2) Temperature rising test

(3) Operation test (4) High voltage test

(5) Insulation resistance test


3. Tests and inspection

(1) The test and inspection methods appropriate by the Society.


are to be in accordance with requirements of KS or as deemed

(2) The overload test provided in Par 2 above is to be carried out continuously under the load of 110 % of the rated output for the duration necessary for saturation of the temperature of each

part plus two hours. However, there is no limit of temperature rise.

(3) Tests and inspection other than those specified in Par 2 above are defined upon agreement be- tween the Society and the manufacturer.

4. Tests of individual electrical equipment after approval

Tests of individual electrical equipment after approval are defined upon agreement between the Society and the manufacturer.


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