A26 contactors are mainly used for controlling 3-phase motors and generally

for controlling power circuits up to 690 V AC or 220 V DC. 

The contactors can also be used for many other applications such as isolation, capacitor switching, lighting. 

The A… series 1-stack 3-pole contactors are of the block type design. 

– Main poles and auxiliary contact blocks: 3 main poles, 1 built-in auxiliary contact, 

front and side-mounted add on auxiliary contact blocks 

– Control circuit: AC operated with laminated magnet circuit

– Accessories: a wide range of accessories is available

The energy needed for operation is not supplied directly by the

auxiliary power supply, but is always “stored” in the capacitor which

acts as an energy accumulator, and therefore operation always takes

place with constant speeds and times, independently of the divergence

of the power supply voltage from the rated value.

The auxiliary power supply has the only aim of keeping the capacitor  charged.

Consumption is therefore minimal. The power required is less than

5 W. In order to re-instate the rated power value in the capacitor

after an operation, there is an inrush of 15 W for a duration of a few

tens of milliseconds. For the reasons indicated above, both for the

DCO and for the SCO version it is necessary to supply the auxiliary

circuits which recharge the capacitor with a continuous auxiliary

power supply of 5W (this value can reach 15W for a few milliseconds

immediately following each operation). Careful selection of the

components and a precise design make the electronic multi-voltage

feeder extremely reliable, unaffected by electromagnetic interference

generated by the surrounding environment and free of any emissions

which may affect other apparatus placed in the vicinity.

These characteristics have made it possible for the V-Contact VSC

contactors to pass the electromagnetic compatibility tests (EMC)

and obtain the CE mark.

ABB has implemented this technology in the field of contactors on

the basis of experience gained in the field of circuit-breakers with

magnetic drive.

The magnetic drive adapts perfectly to this type of apparatus thanks

to its precise and linear travel.

The drive, which is of bistable type, is fitted with an opening and a closing coil.

The two coils – individually energised – allow the drive mobile armature

to be moved from one of the two stable positions to the other.

The drive shaft is solid with the mobile armature and held in position

in a field generated by two permanent magnets (fig. A).

Energising the coil opposite to the magnetic latching position (fig.

A) of the core, the magnetic field is generated (fig. B), which attracts

and moves the mobile armature into the opposite position (fig. C).

Every opening and closing operation creates a magnetic field

concordant with the one generated by the permanent magnets, with

the advantage of keeping the intensity of the field itself constant

during service, regardless of the number of operations carried out.

Electrical life

The electrical life of V-Contact VSC contactors is defined in category AC3.

Interruption principle

The main contacts operate

inside the vacuum

interrupters (the level of

vacuum is extremely high:

13 x 10 -5 Pa).

On opening, there is rapid

separation of the fixed and

moving contacts in each

contactor interrupter.

Overheating of the contacts, generated at the moment they separate,

causes formation of metallic vapours which allow the electric arc

to be sustained up to the first passage through zero current.

On passage of zero current, cooling of the metallic vapours allows

recovery of high dielectric resistance able to withstand high values

of the return voltage.

For motor switching, the value of the chopped current is less than

0.5 A with extremely limited overvoltages.

Compliance with Standards

V-Contact VSC contactors comply with the Standards of the major

industrialised countries and in particular with the IEC 60470 (2000)

and GB/T 14808 Standards.

Operating characteristics

– Ambient temperature: – 5℃… + 40℃

– Relative humidity: < 95 %  (without condensation)

– Altitude: < 1000 m s.l.m.

For other conditions, please contact us.

Main technical characteristics

– Chopping current value ≤0.5 A

– Maintenance-free

​- Suitable for installation in prefabricated substations and switchgear

both of the card (slim line) and traditional type

– High number of operations

– Direct checking of contact wear

– Long electrical and mechanical life

– Remote control

– Multi-voltage feeder

– Bistable drive of the type with permanent magnets

All the contactors mentioned above are available, on request, in one

of the two following versions.

– SCO (Single Command Operated): closing takes place by supplying

auxiliary power to the special input of the multi-voltage feeder. On

the other hand, opening takes place when the auxiliary power is

either voluntarily cut off (by means of a command) or involuntarily

(for lack of auxiliary power in the installation).

– DCO (Double Command Operated): closing takes place by

supplying the input of the closing command of the apparatus in

an impulsive way. On the other hand, opening takes place when

the input of the opening command of the contactor is supplied

in an impulsive way.

Fields of application

The V-Contact VSC contactors are suitable for controlling electrical

apparatus in industry, in the service sector, in the marine sector, etc.

Thanks to the breaking technique with vacuum interrupters, they

can operate in particularly difficult environments.

They are suitable for control and protection of motors, transformers,

power factor correction banks, switching systems, etc. Fitted with

suitable fuses, they can be used in circuits with fault levels up to

1000 MVA (VSC7 – VSC12).

General

The medium voltage V-Contact VSC contactors are apparatus

suitable for operating in alternating current and are normally used

to control users requiring a high number of hourly operations.

The V-Contact VSC contactor introduces the drive with permanent

magnets, already widely used, experimented and appreciated in

medium voltage circuit-breakers, into the worldwide panorama of

medium voltage contactors.

The experience acquired by ABB in the field of medium voltage

circuit-breakers fitted with drives with  “MABS”  permanent magnets,

has made it possible to develop an optimised version of the actuator

(bistable MAC drive) for medium voltage contactors.

The drive with permanent magnets is activated by means of an

electronic multi-voltage feeder. The feeders differ according to the

integrated functions and to the auxiliary power supply voltage.

Three bands of power supply are available with which all the voltage

values required by the major international Standards can be covered.

Each feeder is able to take any voltage value within its own operating band.