06_CONTACTORS_MOTOR_PROTECTIONS.pdf

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Motor starters

Contactor breakers and reversing contactor breakers integral 18, 32 and 63

Characteristics :

pages 21002/2 to 21003/7

Selection guide :

pages 21004/2 to 21004/11

References :

pages 21005/2 to 21006/11

Dimensions, schemes :

pages 21009/2 to 21012/5

General

The equipment in a power switching circuit must perform 4 main functions :

- overload protection,

- short-circuit protection,

- power switching,

- isolation.

These functions are traditionally performed by separate devices which are combined to form a basic assembly, the most

common being :

- fuses + contactor + thermal overload relay,

- circuit breaker + contactor + thermal overload relay.

Integral : a new concept for power switching

Integral 18, 32 and 63 contactor breakers combine all the functions of a power switching assembly up to 63 A in a single

compact device, with performances equal to those of the best specialised devices and conforming to current standards.

High breaking capacity current limiting circuit breaker

For short-circuit protection.

High breaking capacity with short-circuit current limited by ultra-fast tripping.

Contactor

Contactor breaker

integral 18

For automatic and remote control

Operational power for utilisation category AC-3 :

- up to 30 kW at 400/415 V 50 Hz,

- up to 33 kW at 440 V 50 Hz.

Electrical life in number of operating cycles in category AC-3, at 400 V and at rated power :

- 2 million for integral 18,

- 1.5 million for integral 32,

- 1.2 million for integral 63.

Mechanical life in number of operating cycles :

- 20 million for integral 18,

- 10 million for integral 32,

- 5 million for integral 63.

Thermal-magnetic protection module

For protection against overload and overcurrent.

A range of interchangeable modules allows the equipment to be adapted to suit:

i the rated operational current (rating and settings),

i the application:

- motors,

- frequent starting motors,

- distribution circuits.

Protection module

Reversing pairs

i Two 3-pole contactors, horizontally mounted,

- mechanically and electrically interlocked for integral 18,

- mechanically interlocked for integral 32 and 63.

i Can be fitted with the same protection modules and integral contactor breakers

Isolator function

Integral 18, 32 and 63 contactor breakers provide isolator and locking functions conforming to standards IEC 947.

In addition, integral 32 and 63 “LD4” contactor breakers and “LD5” reversing contactor breakers incorporate specific poles

for isolation and locking.

21001/2

Motor starters

Contactor breakers and reversing contactor breakers integral 18, 32 and 63

Characteristics :

pages 21002/2 to 21003/7

Selection guide :

pages 21004/2 to 21004/11

References :

pages 21005/2 to 21006/11

Dimensions, schemes :

pages 21009/2 to 21012/5

General

Signalling and attachments

These devices provide comprehensive local signalling:

- pole position indicator,

- different signalling for overload” and “short-circuit”.

They also allow dialogue with the automated control system by means of numerous add-on blocks:

- auxiliary contact and signalling blocks,

- remote electrical reset device for integral 32 and 63,

- undervoltage and shunt trips for integral 32 and 63,

- control circuit switching,

- etc.

Simple fixing and cabling methods

Integral 18 and 32 contactor breakers and reversing contactor breakers clip directly onto 35 mm " rails

Integral 63 contactor breakers and reversing contactor breakers fit onto 75 mm " rails using a separate mounting plate.

Integral units may also be mounted on:

- panels,

- pre-slotted mounting plates type AM1-P,

- 2 x 32 mm " rails using sliding clip nuts,

- CMD prefabricated plug-in busbar trunking, providing an economical assembly combining safety and simplicity of use,

- AK5 panel busbar systems.

21001/3

Motor starters

Contactor breakers and reversing contactor breakers integral 18, 32 and 63

Terminology

Altitude

The rarefied atmosphere at high altitude reduces the dielectric strength of the

air and hence the rated operational voltage of the contactor breaker. It also

reduces the cooling effect of the air and hence the rated operational current of

the contactor breaker (unless the temperature drops at the same time).

No derating is necessary up to 3000 m.

Derating factors to be applied above this altitude for main pole operational

voltage and current (a.c. supply) are as follows.

Altitude

3500 m

4000 m

4500 m

5000 m

Rated operational voltage

0.90

0.80

0.70

0.60

Rated operational current

0.92

0.90

0.88

0.86

Ambient air temperature

The temperature of the air surrounding the device, measured near to the device.

The operating characteristics are given:

- with no restriction for temperatures between - 5 and + 55

- with restrictions, if necessary, for temperatures between - 50 and + 70

Rated operational current (Ie)

This is defined taking into account the rated operational voltage, operating rate

and duty, utilisation category and ambient temperature around the device.

Rated conventional thermal current

The current which a closed contactor breaker can sustain for a minimum of 8

(Ith) (1)

hours without its temperature rise exceeding the limits given in the standards.

Short time rating

The current which a closed contactor breaker can sustain for a short time after

a period of no load, without dangerous overheating.

Rated operational voltage (Ue)

This is the voltage value which, in conjunction with the rated operational current,

determines the use of the contactor breaker or starter, and on which the

corresponding tests and the utilisation category are based. For 3-phase circuits

it is expressed as the voltage between phases.

Apart from exceptional cases such as rotor short-circuiting, the rated operational

voltage Ue is less than or equal to the rated insulation voltage Ui.

Rated control circuit voltage (Uc)

The rated value of the control circuit voltage, on which the operating characteristics

are based. For a.c. applications, the values are given for a near sinusoidal wave

form (less than 5% total harmonic distortion).

Rated insulation voltage (Ui)

This is the voltage value used to define the insulation characteristics of a device

and referred to in dielectric tests determining leakage paths and creepage

distances. As the specifications are not identical for all standards, the rated

values given for each of them are not necessarily the same.

Rated operational power

The rated power of the standard motor which can be switched by the contactor

(expressed in kW)

breaker, at the stated operational voltage, based on a 4-pole squirrel cage

motor.

Note : these definitions are extracted from standard IEC 947-1.

(1) Conventional thermal current, in free air, conforming to IEC standards.

21001/4

Motor starters

Contactor breakers and reversing contactor breakers integral 18, 32 and 63

Terminology

Rated breaking capacity (1)

This is the current value which the contactor breaker can break in accordance

with the breaking conditions specified in the IEC standard.

Rated making capacity (1)

This is the current value which the contactor breaker can make in accordance

with the making conditions specified in the IEC standard.

On-load factor (m)

This is the ratio between the time the current flows (t) and the duration of the

cycle (T)

m =

Cycle duration: duration of current flow + time at zero current

Pole impedance

The impedance of one pole is the sum of the impedance of all the circuit

components between the input terminal and the output terminal.

The impedance comprises a resistive component (R) and an inductive compo-

nent (X = L

). The total impedance therefore depends on the frequency and is

normally given for 50 Hz. The average value is given for the pole at its rated

operational current.

Electrical durability

This is the average number of on-load operating cycles which the main pole

contacts can perform without maintenance. The electrical durability depends on

the utilisation category, the rated operational current and the rated operational

voltage.

Mechanical durability

This is the average number of no-load operating cycles (i.e. with zero current

flow through the main poles) which the contactor breaker can perform without

mechanical failure

Note : these definitions are extracted from standard IEC 947-1.

(1) For a.c. applications, the breaking and making capacities are expressed by the rms value of the symmetrical

component of the short-circuit current. Taking into account the maximum asymmetry which may exist in the circuit, the

contacts therefore have to withstand a peak asymmetrical current which may be twice the rms symmetrical component.

21001/5

Motor starters

Contactor breakers and reversing contactor breakers integral 18, 32 and 63

Terminology (continued)

Contactor utilisation categories conforming to IEC 947-4

The standard utilisation categories define the current values which the contactor must be able to make or break.

These values depend on:

- the type of load being switched: squirrel cage or slip ring motor, resistors,

- the conditions under which making or breaking takes place: motor stalled, starting or running, reversing, plugging.

a.c. applications

Category AC-1

This category applies to all types of a.c. load with a power factor equal to or

greater than 0.95 (cos

0.95).

Application examples: heating, distribution.

Category AC-2

This category applies to starting, plugging and inching of slip ring motors.

i On closing, the contactor breaker makes the starting current, which is about

2.5 times the rated current of the motor.

i On opening, it must break the starting current, at a voltage less than or equal

to the mains supply voltage.

Category AC-3

This category applies to squirrel cage motors with breaking during normal

running of the motor.

i On closing, the contactor breaker makes the starting current, which is about

5 to 7 times the rated current of the motor.

i On opening, it breaks the rated current drawn by the motor; at this point, the

voltage at the contactor breaker terminals is about 20% of the mains supply

voltage. Breaking is light.

Application examples: all standard squirrel cage motors: lifts, escalators,

conveyor belts, bucket elevators, compressors, pumps, mixers, air conditioning

units, etc... .

Categories AC-4 and AC-2

These categories cover applications with plugging and inching of squirrel cage

and slip ring motors.

On closing, the contactor breaker makes a current peak which may be as high

as 5 or 7 times the rated motor current. On opening it breaks this same current

at a voltage which is higher, the lower the motor speed. This voltage can be the

same as the mains voltage. Breaking is severe.

Application examples: printing machines, wire drawing machines, cranes and

hoists, metallurgy industry.

21001/6

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