Calculation of the temperature rises in compliance with the Std. IEC 60890

Calculation of the powers generated by the different

components and dissipated inside the assembly

 

The calculation of the power losses reported in the

configurations shown is carried out by taking into account

the effective powers dissipated by the different

components.

 

Circuit-breakers

Given the power losses at the rated current (In) shown in

the following tables and the current which actually flows

through the circuit-breakers (Ib), it is possible to calculate

the effective power losses of the equipment:

 

 

The values thus obtained must be increasde by a factor

depending on the circuit-breaker type.

This coefficient is used to take into account the connections

which carry current to the circuit-breakers

Open-type and enclosed assemblies

According to the constructional typology the Standard

IEC 61439-1 distinguishes between open-type and enclosed

assemblies.

 

- Enclosed assembly

 

An assembly is enclosed when there are protected

panels on all its sides so as to provide a degree of

protection against direct contact not lower than IPXXB

(see Chapter 4). Assemblies intended to be installed

in common environments shall be of enclosed type

 

- Open-type assembly

 

An assembly, with or without front covering, in which

the live parts of the electrical equipment are accessible.

Such assemblies can be used only in places

where skilled persons have access for their use.

Rated electrical characteristics of an assembly

Rated voltage (Un)

Highest nominal value of the a.c. (r.m.s) or d.c. voltage,

declared by the assembly manufacturer, to which the

main circuit(s) of the assembly is (are) designed to be

connected. In three-phase circuits, it is the voltage

between phases.

Rated operational voltage (Ue)

it is the rated voltage of a circuit of an assembly which

combined with the rated current of this circuit determines

its application. For three-phase circuits such voltage corresponds

to the voltage between phases.

In an assembly there are usually a main circuit with its

own rated voltage and one or more auxiliary circuits with

their own rated voltages.

The manufacturer of the assembly shall state the limits of

voltage necessary for correct functioning of the circuits

inside the assembly.

 

Rated insulation voltage (Ui)

it is the voltage value of a circuit of an assembly to which test voltages

(power frequency withstand voltage) andthe creepage distances are referred.

The rated voltage of each circuit shall not exceed its

rated insulation voltage.

Rated impulse withstand voltage (Uimp)

it is the peak value of an impulse voltage which the circuit

of an assembly is capable of withstanding under specified

conditions and to which the values of clearances

are referred. It shall be equal to or higher than the values

of the transient overvoltages occurring in the system in

which the assembly is inserted.

Rated current of the assembly (InA)

It is a new characteristic introduced by the Std. IEC

61439 and normally indicates the maximum incoming

permanent and allowable load current or the maximum

current which an assembly is capable of withstanding.

The rated current shall be withstood in any case, provided

that the temperature-rise limits stated by the Standard

are complied with.

Rated current of a circuit (InC)

It is the current value to be carried out by a circuit without

the temperature-rise of the various parts of the assembly

exceeding the limits specified according to the testing

conditions of Clause 7.

Rated short-time current (Icw)

it is the r.m.s. value of the current for the short-circuit test

for 1 s time; such value, declared by the manufacturer

does not imply the opening of the protective device

and is the value which the assembly can carry without

damage under specified conditions, defined in terms of

current and time. Different Icw values can be assigned to

an assembly for different times (e.g. 0.2 s; 3 s). Manufacturer,

can withstand satisfactorily for the operating

time of the device under the specified test conditions.

Rated diversity factor (RDF)

it is the per unit value of the rated current, assigned by

the assembly manufacturer, to which outgoing circuits

of an assembly can be continuously and simultaneously

loaded taking into account the mutual thermal influences.

The rated diversity factor can be stated:

- for groups of circuits;

- for the whole assembly.

The rated diversity factor is:

The rated diversity factor multiplied by the rated current

of the circuits (In) shall be equal to or higher than the

assumed loading of the outgoing circuits (Ib).

The rated diversity factor is applicable to the outgoing

circuits of the assembly and demonstrates that multiple

functional units can be partially loaded.

When the manufacturer states a rated diversity factor,

this factor shall be used for the temperature-rise test,

otherwise reference shall be made to the values recommended

by the Standard 61439-1 in Annex E.

Rated frequency

value of frequency to which the operating conditions are

referred. If the circuits of an assembly are designed for

different values of frequency, the rated frequency of each

circuit shall be given.

-ABB technical application papers

 

 

Design verification of the new standard IEC 61439

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

Explosion Proof Lighting & Power Distribution Panel Board Series

DOWNLOAD :

http://www.akronelectric.com/pdf_files/Explosion-Proof%20Panel%20Boards.pdf

Panelboards P1 thru P5 (Selection & application guide)

DOWNLOAD :

 

http://www.scottelectricusa.com/apparatus/panelboards.pdf

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.

 

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