abb -jkr seminar on iec 60439 and iec 61439 on 18 august 2009

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Sharing session with JKR onIEC 60439 and IEC 61439

Er. Lim Say Leong, Region Marketing Manager, South Asia, Automation Products Division, 18 August 2009

Title:Low voltage switchgear and controlgear assemblies- Requirements of today and tomorrow

Sypnosis:This sharing session covers the current IEC 60439 series and also the development of IEC 61439 for tomorrow.Salient requirements will be presented in details leaving time for discussions such as:

• difference between IEC 60439 and IEC61439,• type tested & partially type tested assemblies,• how to confirm/check construction compliance of

assemblies as per test report,• trend of busbar trunking system, etc.

My talk today

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SituationSituation

Many manufacturers could comply with IEC 60439.

Many also do not comply due to various reasons:

Lack of knowledge.

Difficulties to meet customization of their product.

Product not verified.

Pressure to reduce costs.

IEC – worldwide requirement in a global economy

Share our knowledge and experience

ABB sets the standard

Local presence and expertise

Best technology for the process

Cost-effective solutions

Responsive local service

A supplier with global guidance and direction

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Part 1 Type-tested and partially type-tested

assemblies.

Part 2 Particular requirements for busbar

trunking systems.

Part 3 Particular requirements for

distribution boards.

Part 4 Particular requirements for

assemblies for construction sites

(ACS).

Part 5 Particular requirements for cable

distribution cabinets (CDC).

IEC 60439 - structure

IEC 60890

Method of temperature-rise assessment by extrapolation

for partially type-tested assemblies (PTTA).

IEC 61117

Method of assessing the short-circuit withstand strength

of partially type-tested assemblies (PTTA).

IEC 61641

Guide for testing under conditions of arcing due to

internal fault.

Supported by other IEC specifications

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© ABB Group August 18, 2009 | Slide 7

IEC 60439 series – IEC 60439-1

Part 1

Type-tested and partially type-tested assemblies.



Part 2

Busbar trunking system.

5



Part 3 Distribution boards where unskilled persons have access for their use.



Part 4 Assemblies for construction sites

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Part 5 Cable distribution cabinets (CDCs) power distribution and installed outdoors in public places.


IEC 60439 series

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Standards for switchboards – IEC 60439-1

Specification for type-tested (TTA) and partially type-tested assemblies (PTTA)

Defines and specifies the service conditions, constructional requirements, technical characteristics and tests of TTA & PTTA

Non-prescriptive

Allows the manufacturer to be innovative

Specified as minimum requirements for supplying of switchboards in projects together with ASTA or equivalent Certification locally

A combination of one or more switching devices together

with associated:

control,

measuring,

signaling,

protective,

regulating equipment, etc.,

completely assembled under the responsibility of the manufacturer.


Low voltage switchgear & controlgear assemblies

8


What is TTA and PTTA?

A low voltage switchgear and controlgear assembly conforming to an established type or system without deviations likely to significantly influence the performance, from the typical assembly verified to be in accordance with this standard.

ABB Elettrocondutture

Quadri per distribution

Quadri elettrici per bassa tensione

H. T109-I-01maggio '97

catalogue

TypeType--tested assembliestested assembliesTTATTA

A low voltage switchgear and controlgear assembly containing both type-tested and not type tested arrangements provided that the latter are derived (e.g. by calculation ) from type-tested arrangements which have complied with the relevant tests.

calculation

Partially TypePartially Type--tested assembliestested assembliesPTTAPTTA


Testing of switchboards

1 verify temperature rise limits

2 verify dielectric properties

3 verify short-circuit withstand

4 verify protective circuit effectiveness

5 verify clearances and creepage distances

6 verify mechanical operation

7 verify degree of protection

9 Test 8-3-1: Overall inspection

10 Test 8-3-2 or 8-3-4: Insulation check

11 Test 8-3-3: verify protection measures & electrical continuity of protective circuits

Performed and carried out on a representative unit

Maximum safety and reliability

The 3 routine tests must be carried out on every switchboard

8 Type test8 Type test

+ 3 Routine tests+ 3 Routine tests8 verify emc

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Defined by a number of key parameters.

Specified by the manufacturer, sometimes by agreement

between the manufacturer and user of the equipment.

These characteristics, for example, may depend upon the

environment in which the equipment is required to operate

and the fault level of the supply to the equipment.

The manufacturer must specify the relevant characteristics

for the relevant type-tests to be conducted by the testing

station.


Characteristics of switchboards

Rated Voltage Rated Operational Voltage (Ue)

Rated Insulation Voltage (Ui)

Rated Impulse Withstand Voltage (Uimp)

Rated Current (In)

Rated Short-time Withstand Current (Icw)

Rated Peak Withstand Current (Ipk)

Rated Conditional Short-circuit Current (Icc)

Rated Fused Short-circuit Current (Icf)

Rated Diversity Factor

Rated Frequency


Electrical characteristics of switchboards

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On Nameplates

manufacturer's name or trade mark

type designation or identification number, or any other means of identification making it possible to obtain relevant information from the manufacturer

On Nameplates or Technical documentation

IEC 60439-1;

Type of current (and frequency, in the case of a.c.);

Rated operational voltages (see 4.1.1);

Rated insulation voltages (see 4.1.2);

Rated impulse withstand voltage, when declared by the manufacturer (see 4.1.3);

Rated voltages of auxiliary circuits (if applicable);


Information to be provided

On Nameplates or Technical documentation Limits of operation (see clause 4); Rated current of each circuit (if applicable; see 4.2); Short-circuit withstand strength (see 7.5.2); Degree of protection (see 7.2.1); Measures for protection of persons (see 7.4); Service conditions for indoor use, outdoor use or

special use, if different from the usual service conditions as given in 6.1;

Pollution degree, when declared by the manufacturer (see 6.1.2.3);

Types of system earthing for which the ASSEMBLY is designed;

Dimensions, preferably in the order of height, width (or length), depth;

Weight;


Information to be provided (cont’d)

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On Nameplates or Technical documentation

Form of internal separation (see 7.7);

Types of electrical connections of functional units (see 7.11);

Environment 1 or 2 (see 7.10.1).


Information to be provided (cont’d)

Ambient air temperature

Ambient air temperature for indoor installations

Does not exceed +40 °C and its average over a period of 24 h does not exceed +35 °C.

The lower limit of the ambient air temperature is –5 °C.

Ambient air temperature for outdoor installations

Does not exceed +40 °C and its average over a period of 24 h does not exceed +35 °C.

The lower limit of the ambient air temperature is:

–25 °C in a temperate climate, and

–50 °C in an arctic climate.


Service condition

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Atmospheric conditions

Atmospheric conditions for indoor installations

The air is clean and its relative humidity does not exceed 50 % at a maximum temperature of +40 °C. Higher relative humidity may be permitted at lower temperature, for example 90 % at +20 °C.

Atmospheric conditions for outdoor installations

The relative humidity may temporarily be as high as 100 % at a maximum temperature of +25 °C.


Service condition

Pollution degree

Refers to the environmental conditions for which the ASSEMBLY is intended.

For switching devices and components inside an enclosure, the pollution degree of the environmental conditions in the enclosure is applicable.


Service condition

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Pollution degree (cont’d) To evaluate clearances and creepage distances, the

following four degrees of pollution are established. Pollution degree 1

No pollution or only dry, non-conductive pollution occurs.

Pollution degree 2 Normally, only non-conductive pollution occurs.

Occasionally, however, a temporary conductivity caused by condensation may be expected.

Pollution degree 3 Conductive pollution occurs or dry, non-conductive

pollution occurs which becomes conductive due to condensation.

Pollution degree 4 The pollution generates persistent conductivity

caused, for instance, by conductive dust or by rain or snow.


Service condition

Altitude

Site of installation does not exceed 2 000 m (6 600 ft).

Note: For electronic equipment to be used at altitudes above 1 000 m, it may be necessary to take into account the reduction of the dielectric strength and of the cooling effect of the air.

Electronic equipment intended to operate in these conditions should be designed or used in accordance with an agreement between manufacturer and user.


Service condition

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Mechanical design

Materials capable of withstanding the mechanical, electrical and thermal stresses as well as the effects of humidity which are likely to be encountered in normal service.

Protection against corrosion shall be ensured by the use of suitable materials or by the application of equivalent protective coatings to the exposed surface, taking account of the intended conditions of use and maintenance.

All enclosures or partitions including locking means for doors, withdrawable parts etc., shall be of a mechanical strength sufficient to withstand the stresses to which they may be subjected in normal service.

The apparatus and circuits in the ASSEMBLY shall be so arranged as to facilitate their operation and maintenance, and at the same time to ensure the necessary degree of safety.


Design & construction

Clearances, creepage distances and isolating distances

Clearances and creepage distances

Apparatus forming part of the ASSEMBLY shall have distances complying with the requirements of their relevant specifications, and these distances shall be maintained during normal service conditions.

When arranging apparatus within the ASSEMBLY, the specified creepage distances and clearances or impulse withstand voltages shall be complied with, taking into account the relevant service conditions.

For bare live conductors and terminations (e.g. busbars, connections between apparatus, cable lugs), the creepage distances and the clearances or impulse withstand voltages shall at least comply with those specified for the apparatus with which they are directly associated.



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Clearances, creepage distances and isolating distances (cont’d)

In addition, abnormal conditions such as a short circuit shall not permanently reduce the clearances or dielectric strength between busbars and/or connections other than cables below the values specified for the apparatus with which they are directly associated.

Isolating distances on Withdrawable parts

In the case of functional units being mounted on withdrawable parts, the isolation provided shall at least comply with the requirements in the relevant specification for disconnectors with the equipment in new condition, taking account of the manufacturing tolerances and changes in dimensions due to wear.



Dielectric properties Terminals for external conductors Enclosures and degree of protection Temperature rise Protection against electric shock Short-circuit protection and short-circuit withstand strength Switching devices and components installed in

ASSEMBLIES Internal separation of ASSEMBLIES by barriers or

partitions Electrical connections inside an ASSEMBLY: bars and

insulated conductors Requirements for electronic equipment supply circuits Electromagnetic compatibility (EMC) Description of the types of electrical connections of

functional units



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Switchboards Common problems

SwitchboardsWhat are the common problems?

Overheating

Fire

Electric shock

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How we react?

The usual way is to blame down the chain

Can we overcome it?

Yes

OverheatingWhat causes it?

Poor connection - Mitigation

There is proper tightening torque

Equipment

Value

Correct selection of termination

Regular checking

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Under-size - Mitigation

Correct sizing for cable and busbar.

At termination oversize to have heat-sink effect.

Overdoing it results in costs increase


Ventilations - Mitigation

Heat concentration

Chimney effect

Do not block it

Regular checking and cleaning

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Harmonics - Mitigation

Know the load in advance

Filters

Have sufficient rating for the inductor.

Have capacitor that takes the over-voltage and the flame-retardant

Fire protection• The capacitor elements are surrounded by

vermiculite which is an inorganic, inert, fire-proof and non-toxic granular material. The vermiculite safely absorbs the energy produced within the capacitor box and extinguishes any possible flame.

Thermal equalizers• Thermal equalizers are fitted to surround each

capacitor element and provide effective heat dissipation. The CLMD capacitor is equipped with discharge resistors

High reliability• The CLMD capacitor complies with requirements to

IEC60831-1 & 2 and is UL listed.

Enclosed Capacitor UnitsCLMD

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Poor connection

Under-size

Ventilations

Harmonics

FireWhat causes it?

Flammability of material

Source of ignition

Prolonged overheating

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Electric ShockWhat causes it?

Deterioration of insulation

Access to live parts

Explosion

Flashover

Testing and acceptance

Classification of tests in IEC 60439-1

– type tests

– routine tests

Practice of acceptance – in addition to standard

– Factory acceptance test - FAT

– Site acceptance test – SAT

– Operation and maintenance manual

– O & M

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SwitchboardsTesting & acceptance

Type tests certificate….

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Type tests to verify compliance with standard & carried out on a sample to be manufactured to the same or a similar design.

They shall be carried out on the initiative of the manufacturer.


Routine tests on every production unit intended to detect faults in materials and workmanship.

a) Inspection

b) Dielectric test

c) Checking of protective circuit

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Factory acceptance test

Materials and construction

Setting and verifying

Site acceptance test

Transportation damage

Setting, sealing, signed off

Operation and maintenance manual

Learning to use and maintenance


SwitchboardsProtection against overvoltages

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overvoltage category a conventional number based on limiting (or controlling) the

values of prospective transient overvoltages occurring in a circuit (or within an electrical system having different nominal voltages) and depending upon the means employed to influence the overvoltages.

surge arrester a device designed to protect the electrical apparatus from high

transient overvoltages and to limit the duration and frequently the amplitude of the follow-on current

Overvoltage requirement for IEC 60439-1

Overvoltages Supply overvoltages are specified in figure 1. This figure applies to the non-periodic overvoltages as a deviation from

the rated peak value within the short-time range. The ASSEMBLIES shall be so designed that their service ability in the

case of overvoltages below the values represented by curve 1 is ensured.

If overvoltages occur within the range between curves 1 and 2, the operation may be interrupted by the response of protective devices safeguarding the ASSEMBLY, no damage to the ASSEMBLY being allowed to occur up to a peak value of the voltage equal to 2 Ui + 1 000 V.


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Temporary variations in voltage and frequencyThe equipment shall operate without damage when there are temporary variations in the following conditions. voltage drops not exceeding 15 % of rated voltage for periods not

longer than 0,5 s. supply frequency deviation of up to + 1% of rated frequency. the maximum admissible duration of an interruption of the supply

voltage for equipment shall be indicated by the manufacturer.


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400 V~ 230 V~ 230 V~ 60 V~6000 V

4000 V2500 V

1500 V

IV III II I

System voltageUimp

Category

Impulse withstand voltages

category to IEC 60364-4-44 ,

60439 and 60947.


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Category IV

• Origin of installation

•overhead lines

•cable networks

•busbars

•cutouts

Category III

• Distribution circuit

• final circuit

•stationary installation

Category II

• Load level

•portable equipment

Category I• Special

equipment

• communi-cation equipment

• electronics

Location of SPD to IEC 60439-1

Category IV

• 6 kV

• 25 kA 10/350

• class 1

Category III

• 4 kV

• 10 kA 8/20

• class 2

Category II

• 2.5 kV

• 1.5 kA 8/20

• class 3

Category I

• 1.5 kV

Location of SPD to IEC 60439-1

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Increasing propagation of disturbance :

• interconnection and complexity of power and telecommunication networks.

• switching operations of power electronics.

Why to protect against overvoltage?

Decreasing robustness of equipment :

• sensitive electronic equipments

• telecommunication equipments

Why to protect against overvoltage?

Statistics from insurance shows high percentage of damage to electronics due to overvoltages

Damage to semiconductor device due to overvoltage

Loss of operation

Loss of service

Loss of data

Loss of production

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Lightning surge

Switching surge

Purpose of SPD

What is an overvoltage?

Enemy of SPD

Vrms230V 50Hz

8000V during 140µs8000V during 140µs

Transient overvoltage

460V during 10s460V during 10s

Temporary overvoltage

Lightning strikes direct lightning strike

Direct lightning strike on a lightning rod

Close lightning strike on aerial line

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T IM E

V A LU Ein kA

Lightning strikes 10/350 waveshape

(µµµµs)

50%

350µµµµs

Iimp

90%

10%

10µµµµs

10/350

10/350 wave shape

10/350 is used to testType 1

Inductive coupling Earth potential rise

Lightning strikes indirect lightning strike

Distant lightning strike on aerial line

+ switching

operations

• Capacitive and inductive equipments are switched on or off

• Fuse or breaker operations

• Power electronics

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Lightning strikes 8/20 waveshape

8/20 wave shape

TIME

VALUE

(µµµµs)

I

Imax

50%

20µµµµs

90%

10%

8µµµµs

8/20

8/20 is used to testType 2 and Type 3

Comparison of the energy

T IM E in us

V A LU Ein kA

10/350

8/20

10/350 energy >> 8/20 energy

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Data from Meteorage. Measurement campaign on 5.4Million strokes between 1995-2005

Amplitude of Lightning Strokes (kA)

0%

20%

40%

60%

80%

100%

0 20 40 60 80 100 120 140 160 180 200

Amplitude of lightning strokes (kA)

Cum

ulat

ive

freq

uenc

y

40% of lightning strikes are higher than 20kA (or 60% of lightning strikes are below 20kA)

5 % of lightning strikes are higher than 60kA (or 95% of lightning strikes are below 60kA)

0.1 % of lightning strikes are higher than 200kA

Strike size and frequency

Cumulative frequency of lightning strikes –positive and negative- versus their amplitude.

200 kA

4××××8,3 kA

PE TVnetwork

water and gas pipespower network

10 Ω

100 kA

100 kA

33 kA33 kA

33 kA

Typical current sharing on direct strike (10/350)

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OVR … Over Voltage Range

IEC EN NFC VDE UL

CLASS A

TYPE I TYPE I CLASS B

TYPE II TYPE II “SPD” CLASS C

TYPE III TYPE III CLASS D “TVSS”

International Europe France Germany United states

Withstand of equipment

Overvoltage value due to lightning or switching : 500V to 200 000V

Equipments are divided into withstand categories :

Category IV : Industrial equipment, meters overvoltage < 6000V

Category III : Distribution panels, switchgear overvoltage < 4000V

Category II : Domestic electrical equipment overvoltage < 2500V.

Category I : Sensitive electronic circuits overvoltage < 1500V

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Level of protection = Up

SPDUp=1,2kV

UnetworkEquipment

UProtected

Iimp: OVR T1 25-255

T IM E

V A LU Ein kA

(µµµµs)

50%

350µµµµs

Iimp

90%

10%

10µµµµs

10/350

15kA 10/350Iimp

7kA 10/350

25kA 10/350

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Imax: OVR T2 40-275 s P TS

8/20 wave shape

TIME

VALUE

(µµµµs)

I

Imax

50%

20µµµµs

90%

10%

8µµµµs

8/20

40kA 8/20Imax

15kA 8/20

70kA 8/20

Type I+II / Combined SPD

OVR T1+2 25 255 TS OVR T1+2 7 275s P

Wave shape 10/350 10/350 & 8/20

Techno Spark Gap + MOV MOV

Iimp 25kA 7kA

Imax - 70kA

Up 1,5kV 1,5kV

Reason to call the SPD T1+2

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When the surge comes, the electronic will detect and

amplify it

At this stage, a little spark is

generated at the needle head

Once the surge is earthed, arc enters

in the arc chamber. this is

self extinguishingtime

Hot gas exit passing through

the exhaust channel that avoid

any fire risks

Little spark commutes the air gap, thus surge

energy is driven to ground

OVR T1 25-255

Type I+II / Combined SPD


IEC 61439 seriesNow and the future

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Towards the future - IEC 61439

What would it be IEC 61439?

39

Part 1 General rules

Part 2Power

switchgear & Controlgear Assemblies

Part 4Assemblies

for Construction

Sites

Part 5Assemblies for Power

Distribution

Part 3Distribution

Boards

Part 6Busbar trunking Systems

IEC 61439 – Structure

• IEC 61439 provides detail guidelines on how to

prove that assemblies derived from fully type-

tested assemblies comply with the new standard.

• IEC 60439 standard was not so easy to assess

whether partially type tested assemblies are

compliant.

• IEC 61439 standard will specify:

• by testing

• by calculations

• by design rules

New world standard

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IEC 60439 – Future classification – IEC 61439

Today, due to a lack of clarity of IEC 60439 there is wide

range of interpretations on:

• How to carry out the verification,

• What is the acceptance criteria, and

• How many required number of verifications on

different specimen.

Verification by

• Type test

• Calculation

• Design rules


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Previous ambiguities have been addressed, e.g. diversity, rating of circuits and substitution of devices.

The standard requires that the performance of every assembly is demonstrated at design and manufacturing stages by a combination of stringent and defined verification processes :–

• proving tests, • inspection, • design rules and/or calculation.

The new structure

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• Tests carried out on devices to their own product

standard do not need to be duplicated when installed in

an assembly.

• The new standard fully recognises the use of

switchboards assembled from kit systems in accordance

with the original manufacturer’s instructions.

• The verification process no longer recognizes the

classifications of TTA. and PTTA., alternative and

equivalent methods to type tests are included

The new structure

• Tests carried out on devices to their own product

standard do not need to be duplicated when installed in

an assembly.

• The new standard fully recognises the use of

switchboards assembled from kit systems in accordance

with the original manufacturer’s instructions.

• The verification process no longer recognizes the

classifications of TTA. and PTTA., alternative and

equivalent methods to type tests are included

The new structure

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ArTu K

The completely type tested assembly (TTA) and competitive solution

designed to be assembled by an Authorized Panel builder

In kit form

mainly for power distribution.

A pre-engineered product from to be assembled by Authorized Panel builder

Main characteristics

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Integrated range of structures up to 4000A with common accessories

Possibility of fullfilling all application requirements in terms of installation and degree of protection (IP31, IP41, IP42, IP65)

Maximum integration with the ABB Components

Segregations in kits up to Form 4


ArTu complies with the CEI EN60439 Standards

ArTu has obtained ACAE/LOVAG & ASTA Certification

Production system certified ISO 9001 and ISO 14000

ArTu is in accordance with UL50 and UL891


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Rated service voltage: up to 690VRated insulation voltage: up to 1000VRated impulse withstand voltage: 8KV

Dielectric properties (ref. para. 8.2.2 of the standard)

Temperature limits are within the limits specified in the standard and tested for rated current 4000A

Temperature rise (ref. para. 8.2.1 of the standard)

ArTu K Switchboards have undergone TTA tests foreseen by IEC 439-1 in the ABB & Falcon laboratories. The results guarantee the performance of ArTu K by using the structures and ABB SACE circuit breakers, therefore the assembler does not have to carry out any further type test by following the selection criteria and the assembly instruction for the various components

Compliance with IEC 60439-1 Standard

Rated short time short circuit current: 105 KA (1s) & 50 KA (3s)Rated max. Pick short circuit current: 254 KA

Short circuit withstand current (ref. para. 8.2.3 of the standard)

Protection circuit short circuit withstand current:Phase-earthing busbar: 60 KA (1s)

Short circuit efficiency (ref. para. 8.2.4 of the standard)


Mechanical operation (ref. para. 8.2.6 of the standard)

Without door : IP 31Without door : IP 41With door: IP 65

Degree of protection (ref. para. 8.2.7 of the standard) & to IEC 529

Mechanical operation is verified by following the assembly and mounting instruction of the metal workstructures and ABB SACE circuit breaker

The insulation distances are guaranteed by following the ABB SACE assembly & mounting instructions, and those for ABB SACE circuit breakers

Insulation distances (ref. para. 8.2.5 of the standard)

Impact resistance IKStrong structure and tempered glass

Impact energy in Joules: 20.00

40c

m 5kg

ABB Declaration of conformity

We confirm that ArTu K has undergone all the above tests and declared TTA by ACAE-LOVAG certification authority


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ArTu K Modular Switchboards

Distribution Systems

A complete system:

Busbars with shaped section up to 3200A

Flat Drilled Busbars up to 4000A

Compliance to IEC60439-1

Simple to assemble

ArTu K Modular Switchboards

Rapid coupling

Advantages of the Busbar Systems

Easy & fast in mounting

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ArTu Distribution Switchboards

Segregations

ArTu is available with or without segregations

Comply with IEC 60439-1

Segregation Compartments available as:- Form 2- Form 3A and 3B- Form 4

Simple kit to convert from Form 3 to Form 4 Form 4 available both for MCCBs and ACBS Maintenance without Service Interruption

IEC 61439 – the new standard for low-voltage

switchgear and controlgear assemblies – was

issued Jan 2009.

One of the main improvements is that the

definition of fully Type Tested Assemblies (TTA)

and Partially Type Tested Assemblies (PTTA)

have been removed from the standard.

New world standard

48

IEC 61439 provides detail guidelines on how to

prove that assemblies derived from fully type-

tested assemblies comply with the new standard.

IEC 60439 standard was not so easy to assess

whether partially type tested assemblies are

compliant.

IEC 61439 standard will specify:

by testing

by calculations

by design rules

New world standard

If we have existing products that have already

been tested properly, this will not affect your IEC

60439 certification.

Tendency to provide more proof that their

product families follow the correct design

guidelines and rules to comply with IEC 61439.

It is no longer acceptable to provide an assembly

without a full design being fully proven.

It is difficult to make substitutions of one

component or product for another without

stringent assurances

How it affects us?

49

Certification and acceptance of products from IEC 60439 to

IEC 61439.

Moving our MS to IEC 61439

It is no longer acceptable to provide an assembly without a

full design being fully proven.

It is difficult to make substitutions of one component or

product for another without stringent assurances.

How it affects us?

Smissline

[email protected]

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abb -jkr seminar on iec 60439 and iec 61439 on 18 august 2009

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