Monday, December 2, 2013

Friday, November 29, 2013

IEC standards

IEC 60038 Standard voltages

IEC 60076-2 Power transformers - Temperature rise

IEC 60076-3 Power transformers - Insulation levels, dielectric tests and external clearances in air

IEC 60076-5 Power transformers - Ability to withstand short-circuit

IEC 60076-10 Power transformers - Determination of sound levels

IEC 60146 Semiconductor convertors - General requirements and line commutated convertors

IEC 60255 Electrical relays

IEC 60265-1 High-voltage switches - High-voltage switches for rated voltages above 1 kV and less than 52 kV

IEC 60269-1 Low-voltage fuses - General requirements

IEC 60269-2 Low-voltage fuses - Supplementary requirements for fuses for use by unskilled persons (fuses mainly for household and similar applications)

IEC 60282-1 High-voltage fuses - Current-limiting fuses

IEC 60287-1-1 Electric cables - Calculation of the current rating - Current rating equations (100% load factor) and calculation of losses - General

IEC 60364 Electrical installations of buildings

IEC 60364-1 Electrical installations of buildings - Fundamental principles

IEC 60364-4-41 Electrical installations of buildings - Protection for safety - Protection against electric shock

IEC 60364-4-42 Electrical installations of buildings - Protection for safety - Protection against thermal effects

IEC 60364-4-43 Electrical installations of buildings - Protection for safety - Protection against overcurrent

IEC 60364-4-44 Electrical installations of buildings - Protection for safety - Protection against electromagnetic and voltage disrurbance

IEC 60364-5-51 Electrical installations of buildings - Selection and erection of electrical equipment - Common rules

IEC 60364-5-52 Electrical installations of buildings - Selection and erection of electrical equipment - Wiring systems

IEC 60364-5-53 Electrical installations of buildings - Selection and erection of electrical equipment - Isolation, switching and control

IEC 60364-5-54 Electrical installations of buildings - Selection and erection of electrical equipment - Earthing arrangements

IEC 60364-5-55 Electrical installations of buildings - Selection and erection of electrical equipment - Other equipments

IEC 60364-6-61 Electrical installations of buildings - Verification and testing - Initial verification

IEC 60364-7-701 Electrical installations of buildings - Requirements for special installations or locations - Locations containing a bath tub or shower basin

IEC 60364-7-702 Electrical installations of buildings - Requirements for special installations or locations - Swimming pools and other basins

IEC 60364-7-703 Electrical installations of buildings - Requirements for special installations or locations - Locations containing sauna heaters

IEC 60364-7-704 Electrical installations of buildings - Requirements for special installations or locations - Construction and demolition site installations

IEC 60364-7-705 Electrical installations of buildings - Requirements for special installations or locations - Electrical installations of agricultural and horticultural premises

IEC 60364-7-706 Electrical installations of buildings - Requirements for special installations or locations - Restrictive conducting locations

IEC 60364-7-707 Electrical installations of buildings - Requirements for special installations or locations - Earthing requirements for the installation of data processing equipment

IEC 60364-7-708 Electrical installations of buildings - Requirements for special installations or locations - Electrical installations in caravan parks and caravans

IEC 60364-7-709 Electrical installations of buildings - Requirements for special installations or locations - Marinas and pleasure craft

IEC 60364-7-710 Electrical installations of buildings - Requirements for special installations or locations - Medical locations

IEC 60364-7-711 Electrical installations of buildings - Requirements for special installations or locations - Exhibitions, shows and stands

IEC 60364-7-712 Electrical installations of buildings - Requirements for special installations or locations - Solar photovoltaic (PV) power supply systems

IEC 60364-7-713 Electrical installations of buildings - Requirements for special installations or locations - Furniture

IEC 60364-7-714 Electrical installations of buildings - Requirements for special installations or locations - External lighting installations

IEC 60364-7-715 Electrical installations of buildings - Requirements for special installations or locations - Extra-low-voltage lighting installations

IEC 60364-7-717 Electrical installations of buildings - Requirements for special installations or locations - Mobile or transportable units

IEC 60364-7-740 Electrical installations of buildings - Requirements for special installations or locations - Temporary electrical installations for structures, amusement devices and booths at fairgrounds, amusement parks and circuses

IEC 60427 High-voltage alternating current circuit-breakers

IEC 60439-1 Low-voltage switchgear and controlgear assemblies - Type-tested and partially type-tested assemblies

IEC 60439-2 Low-voltage switchgear and controlgear assemblies - Particular requirements for busbar trunking systems (busways)

IEC 60439-3 Low-voltage switchgear and controlgear assemblies - Particular requirements for low-voltage switchgear and controlgear assemblies intended to

be installed in places where unskilled persons have access for their use - Distribution boards

IEC 60439-4 Low-voltage switchgear and controlgear assemblies - Particular requirements for assemblies for construction sites (ACS)

IEC 60446 Basic and safety principles for man-machine interface, marking and identification - Identification of conductors by colours or numerals

IEC 60439-5 Low-voltage switchgear and controlgear assemblies - Particular requirements for assemblies intended to be installed outdoors in public places - Cable distribution cabinets (CDCs)

IEC 60479-1 Effects of current on human beings and livestock - General aspects

IEC 60479-2 Effects of current on human beings and livestock - Special aspects

IEC 60479-3 Effects of current on human beings and livestock - Effects of currents passing through the body of livestock IEC 60529 Degrees of protection provided by enclosures (IP code)

IEC 60644 Spécification for high-voltage fuse-links for motor circuit applications

IEC 60664 Insulation coordination for equipment within low-voltage systems

IEC 60715 Dimensions of low-voltage switchgear and controlgear. Standardized mounting on rails for mechanical support of electrical devices in switchgear and controlgear installations.

IEC 60724 Short-circuit temperature limits of electric cables with rated voltages of 1 kV (Um = 1.2 kV) and 3 kV (Um = 3.6 kV)

IEC 60755 General requirements for residual current operated protective devices

IEC 60787 Application guide for the selection of fuse-links of high-voltage fuses for transformer circuit application

IEC 60831 Shunt power capacitors of the self-healing type for AC systems having a rated voltage up to and including 1000 V - General - Performance, testing and rating - Safety requirements - Guide for installation and operation

IEC 60947-1 Low-voltage switchgear and controlgear - General rules

IEC 60947-2 Low-voltage switchgear and controlgear - Circuit-breakers

IEC 60947-3 Low-voltage switchgear and controlgear - Switches, disconnectors, switch-disconnectors and fuse-combination units

IEC 60947-4-1 Low-voltage switchgear and controlgear - Contactors and motor-starters - Electromechanical contactors and motor-starters

IEC 60947-6-1 Low-voltage switchgear and controlgear - Multiple function equipment - Automatic transfer switching equipment

IEC 61000 Electromagnetic compatibility (EMC)

IEC 61140 Protection against electric shocks - common aspects for installation and equipment

IEC 61557-1 Electrical safety in low-voltage distribution systems up to 1000 V AC and 1500 V DC - Equipment for testing, measuring or monitoring of protective measures - General requirements

IEC 61557-8 Electrical safety in low-voltage distribution systems up to 1000 V AC and 1500 V DC - Equipment for testing, measuring or monitoring of protective measures

IEC 61557-9 Electrical safety in low-voltage distribution systems up to 1000 V AC and 1500 V DC - Equipment for insulation fault location in IT systems

IEC 61557-12 Electrical safety in low-voltage distribution systems up to 1000 V AC and 1500 V DC - Equipment for testing, measuring or monitoring of protective measures. Performance measuring and monitoring devices (PMD)

IEC 61558-2-6 Safety of power transformers, power supply units and similar - Particular requirements for safety isolating transformers for general use

IEC 62271-1 Common specifications for high-voltage switchgear and controlgear standards

IEC 62271-100 High-voltage switchgear and controlgear - High-voltage alternating-current circuit-breakers

IEC 62271-102 High-voltage switchgear and controlgear - Alternating current disconnectors and earthing switches

IEC 62271-105 High-voltage switchgear and controlgear - Alternating current switch-fuse combinations

IEC 62271-200 High-voltage switchgear and controlgear - Alternating current metal-enclosed switchgear and controlgear for rated voltages above 1 kV and up toand including 52 kV

IEC 62271-202 High-voltage/low voltage prefabricated substations

Clearances & Creepage distances for LV panel boards

Clearances distances

Shortest distance in the air between two live conductors or between live

Conductors and exposed conductive parts.

14 mm for 12 kV impulse voltage

8 mm for 8 kV impulse voltage

5.5 mm for 6 kV impulse voltage

The IEC 60439-1 and IEC 61439-2 standards stipulate the minimum clearances

Required to withstand impulse voltage up to 2000 m above sea level.

Pollution degree 3.

 

Creepage distances

Shortest distance along an insulated material surface between two live

Conductors or between live conductors and exposed conductive parts.

16 mm for rated insulation voltage 1000 V AC and DC

12.5 mm for rated insulation voltage 750 V AC and DC

8 mm for rated insulation voltage 500 V AC and DC

See IEC 60439-1 and IEC 61439-2 table 16.

 

Pollution degree 3,

Material group 3a.

 

MILLIVOLT DROP TEST

The millivolt drop test is generally associated with

testing for weld quality on the armature. It is the

best test for verifying armature weld quality.

The millivolt drop test is the ultimate electrical test

for detecting bad welds. Unfortunately, it is

difficult to make on armatures with large diameter

wire and nearly impossible to make on armatures

with small wires.

The difficulty is breaking through the insulation on

the wire as it exits the tang or commutator bar

contact. The one testing contact, usually a sharp

knife edged probe, from the KOM (Kelvin Ohm

Meter) can cut through small wires and destroy

the armature. Contact with the knife-edge probe

needs to be made on each bar. Since this is such

a difficult test to perform, it is only practical as a

laboratory test.

Various test methods have been developed over

the last twenty years that come close to making

this test. These tests make it possible to test

100% of the armatures. However, none of these

tests are as accurate or repeatable as the Millivolt

Drop Test.

ESW's weld test, which uses techniques that have

been developed over the past 20 years, comes

very close to the Millivolt Drop Test. The

repeatability and speed of the test using a

stationary armature test fixture assures that a

reliable test has been performed.

 

Saturday, November 9, 2013

The new IEC 61439 standard

The new IEC 61439 standard applies to enclosures

for which the rated voltage is under 1000 V AC

(at frequencies not exceeding 1000 Hz) or 1500 V DC.

The standard defines the design verified ASSEMBLIES

and eliminates completely the categories TTA and PTTA.

In order to conform to the standard, type tests have been

replaced by a design verification which can be carried

out by the three following equivalent and alternative

methods: testing, calculation/measurement or

application of design rules.

 

The following parts are mentioned and do not have equal

weighting. There is a formal hierarchy. Each part cannot be

used individually:

 

−− IEC 61439-1 "General rules"

−− IEC 61439-2 "Power switchgear and control gear ASSEMBLIES"

−− IEC 61439-3 "Distribution boards"

−− IEC 61439-4 "ASSEMBLIES for construction sites"

−− IEC 61439-5 "ASSEMBLIES for power distribution"

−− IEC 61439-6 "Busbar trunking systems"

 

Part 1 is the general rules part and cannot be used alone to

specify an ASSEMBLY.

 

Part 2 defines the specific requirements of power switchgear

and controlgear ASSEMBLIES (PSC ASSEMBLIES) and must

be used with Part 1. This is the only part that has a double

role, it covers PSC ASS EMBLIES and any ASS EMBLY which

is not covered by any other specific parts.

 

Parts 3-X are still under preparation but are already mentioned

in Part 1. These could be more than four, as additional

parts may be developed as the need arises.

 

Summarising:

With the currently used IEC 60439, the rule

is "one part for each type of ASS EMBLY". With the new

IEC 61439 the rule is "two parts for each type of ASSEMBLY".

The compliance of an ASSEMBLY is declared referring

to the specific ASS EMBLY standard (e.g. IEC 61439-2),

and the compliance with the general rules (IEC 61439-1) is

always implicit. The sentence "TTA switchgear according to

IEC 60439-1" is now replaced by "Power switchgear and

 

controlgear

ASSEMBLIES according to IEC 61439-2, design

verified ASS EMBLY".

The validity of the two standards will overlap until 2014 and

prior to this date, ASSEMBLIES can be manufactured according

to IEC 61439 or IEC 60439.

 

Copyright by :

ABB The new standard for low-voltage

switchgear and controlgear assEmblies

IEC 60529 First Characteristic Numeral Degrees of Protection - Water

INDOOR

 

IP X1 Vertical Falling Drops           10 Min. Drip Test                              Limited Water Inside;

Not on Live Parts

 

IP X2 15° Vertical Falling Drops    10 min. 15° Drip Test                       Limited Water Inside;

Not on Live Parts

 

IP X3 Spraying Water                      5 min. 120° Oscillating Tube or

5 min. Partial Spray

Limited Water Inside;

Not on Live Parts

 

IP X4 Splashing Water                    10 min. 360° Oscillating Tube

or 5 Min. Full Spray

Limited Water Inside;

Not on Live Parts

 

IP X5 Waterjets                                                 Fire Hose 3.3 gal. (12.5L)/min      Limited Water Inside;

Not on Live Parts

 

OUTDOOR

 

IP X6 Powerful Waterjets             Fire Hose 26 gal. (100L)/Min.       Limited Water Inside;

Not on Live Parts

 

IP X7 Temporary Submersion at Limited Depth   Submerge 3 ft. (1m) – 30 Min.    Limited Water Inside;

Not on Live Parts

 

IP X8 Prolonged Submersion at  Limited Depth More Severe Than X7 Customer Agreement         Limited Water Inside;

Not on Live Parts

IEC 60529 First Characteristic Numeral Degrees of Protection - Solids

>> IEC 60529 First Characteristic Numeral Degrees of Protection – Solids

 

Protection Test Method Pass Criteria

 

INDOOR

 

IP 1X Incidental Contact & Solid Objects Ø 50 mm – Probe No Penetration

IP 2X Incidental Contact & Solid Objects Ø 12.5 mm – Probe No Penetration

IP 3X Incidental Contact & Solid Objects Ø 2.5 mm – Probe No Penetration

IP 4X Incidental Contact & Solid Objects Ø 1.0 mm – Probe No Penetration

 

OD

 

IP 5X Dust Protected Circulating Dust Limited Dust Inside; Not on Live Parts

IP 6X Dust Tight Circulating Dust No Dust Inside

 

Thursday, October 24, 2013

Methods of explosion protection for electrical equipment

METHODS OF EXPLOSION PROTECTION

Method                                                                                               Type of Protection

Designed to prevent any means of ignition arising            Ex e Increased Safety

Ex n or Ex N Non Sparking

Designed to limit the ignition energy of the circuit            Ex I Intrinsic Safety

Designed to prevent the flammable mixture reaching    Ex m Encapsulation

a means of ignition                                                                          Ex p Pressurisation

Ex o Oil Immersion

Ex nR or Ex N Restricted Breathing

Designed to prevent any ignition from spreading              Ex d Flameproof Enclosure

Ex q Powder Filling

 

Saturday, October 19, 2013

Minimum terminal capacity for copper protective conductors (PE, PEN)

CROSS-SECTIONAL AREA OF PHASE CONDUCTORS S
MM2

MINIMUM CROSS-SECTIONAL AREA OF THE CORRESPONDING PROTECTIVE CONDUCTOR (PE, PEN) SPA
MM2

S ≤ 16

S

16 < S ≤ 35

16

35 < S ≤ 400

S/2

400 < S ≤ 800

200

800 < S

S/4

a Current in the neutral may be influenced where there are significant harmonics in the load.

Minimum terminal capacity for copper protective conductors (PE, PEN)

Source: IEC 61439-1 2011 Table 5

 

Saturday, October 12, 2013

Standard-compliant switchgear and controlgear production (Application of IEC 61439)

 

A new standard. A new opportunity. 3

Contents 4

One standard for all switchgear and controlgear assemblies 6

What has changed under the new standard? 8

What does the new standard mean for you? 10

Rittal – The System.

Complete solutions – Customised for IEC 61439 12

Strength of materials 14

Protection category of enclosures 16

Verification of protective circuit function 18

Insulating properties 20

Calculation of temperature rise 22

Tested busbar technology 24

The system for the standard 26

 

Preparation of the design verification 28

 

I. The design verification 29

II. Individual verifications and verification methods 31

III. Information included in the design verification 32

IV. Sample design verification 44

V. Verification of temperature rise using calculations 48

VI. Verification of short-circuit withstand strength 66

VII. Verification records of individual

switchgear and controlgear assemblies 70

VIII. The routine verification 73

IX. Complete verification of a switchgear and

controlgear assembly 78

X. Assembly cover sheet and design verification form 80

 

Copyright: c 2013 Rittal GmbH & Co. KG

 

DOWNLOAD :

http://www.rittal.com/belgium/downloads/brochures/eng/IEC61439_compliant_switchgear_controlgear_production.pdf