Product category : Circuit breakers

Stelmac offers indoor vcb panel.
Construction
To efficiently meet the operational requirements in electrical distribution systems, stelvac switchgear is designed with following central consideration:
Continuity in service
Safety of operating personnel
Easy and minimal maintenance
Adaptability of future requirements
Stelvac panels are used to form distribution switch boards or motor control center up to 12 kv. Stelvac panels are metal clad factory built assemblies fully complying with national / international standards. The stelvac panels are metal clad construction having following compartments:

Circuit breaker compartment.
Bus bar compartment.
Cable compartment.
Low voltage control, protection and metering compartment.
Voltage transformer compartment.
Earthed sheet metal partitions separate the compartments, making safe working in a compartment possible when adjacent compartments are live.

Stelvac panels are provided with draw-out type vacuum circuit breakers type vc-32. Draw out construction enables shut down of any one feeder, on which some work can be carried out, keeping other feeder operational. The insertion / withdrawal of a circuit breaker can be provided with front door closed for added safety of operating personnel. The draw out c.B. Has three distinct positions.

Service position - primary and secondary circuit connected.
Test position - primary circuit isolated and secondary circuit connected.
Isolated position - primary and secondary circuit isolated.

The breaker is provided with standard interlocks to ensure Circuit breaker movement from one position to another is possible only when breaker is in off condition. Circuit breaker cannot be inserted in service position without making secondary plug socket connection.

The compartment door can be kept closed when circuit breaker is in test position. The circuit breaker is mounted on its own trolley and no separate trolley is required for movement.

Interchangeability of the panel and breaker is ensured by rigid construction [eliminating possibility of deformation] and use of accurate production and assembly tools and jigs.

The circuit breaker is equipped with a common drive for three interrupters housed in epoxy resin cast housing. Operating mechanism is motorized spring charged stored energy mechanism and is suitable for auto reclosing duty.

Maintenance free, high endurance vacuum interrupters ensure that the maintenance is minimal and restricted to only spring charged mechanism.

The stelvac panels are extensible on both sides thus ensuring easy adaptability to the future requirements. Bus bar and jumpers are rectangular copper or aluminum sections, rigidly supported on epoxy resin cast insulators. The bus bar compartment is accessible from sides and top. The cable compartment access is from rear. The compartment also houses epoxy resin cast current transformer. If required, potential transformer in fixed execution can be provided in cable compartment. Line voltage transformer can also be provided in draw out execution mounted on rear top. Low voltage compartment houses relays, meters, selector/control switches, fuses etc. In the easily accessible locations.

Standards:
The stelvac panels comply with the following standards:
Is: 3427 and is: 13118
Iec: 62271 - 100
Iec: 62271 - 200

All types of tests have been carried out with circuit breaker inside the enclosure.
The panels with vcb type vc32 offers a fully type tested solution for distribution application.

Standard accessories of circuit breakers:
Spring charged motor 220v dc/ 230v ac
Closing coil- all standard ac/dc voltage
Trip coil- all standard ac / dc voltages
Auxiliary contacts up to 8no+8nc
Operation counter
Manual spring charging, closing and tripping
Circuit breaker on, off and spring charged indication

Optional accessories:
If required following can be provided:
Earthing switch
Earthing trolley