Vacuum-circuit :
  36~40.5KV VACUUM CIRCUIT BREAKER : 1250A, 2000A

  • The trend in interrupter design is to continuously reduce the vacuum envelope size and enhance short-circuit capability at the same time. VCB designs are continuously reviewed and upgraded to keep up with the latest developments in vacuum technology.

    Maintenance - The VCB requires minimal maintenance. Its design life-span is 20years or 10000 operations.

    Namenclature - The model numbers of VCB's observe the following nomenclature.

A motor charged spring, stored energy mechanism with manual and electrical release is offered as standard Standard control voltage is 110V DC.
In the double-busbar models, the VCB assembly as mounted on a lifter which raises and lowers the VCB to engage on to "Reserve" or "Main" busbars by means of a "Jackscrew" built into the VCB truck.
The VCB has to be withdrawn to the "Disconnected" position before it can be raised or lowered. thus effectively eliminating ant possibility of operator error.

VCB Data and Specifications
Model VW Single busbar Double busbar
30M25 30P25 30M32 30P32 30M25D 30P25D
RATED Voltage (kV) 36 ~ 40.5*
Insulation Level
Impulse (kVp)
1min Power Freq (kV)
Frequency (Hz) 50/60
Normal Current (A) 1250 2000 1250 2000 1250 2000
Short-circuit Breaking Current (kA) 25 31.5 25
Transient Recovery Voltage (kVp) 62
Short-circuit Making Current (kAp) 63 80 63
Operating Sequence 0-0.3 Sec - CO - 3min - CO
Duration of short-circuit (kAp) 3
Operation Time (mS) 20
Break Time (mS) 3 cycles
Closing Time at No load (mS) 50
Closing Voltage (V.d.c)
Closing Current (A)
Closing Voltage (V.d.c)
Closing Current (A)
Full load Switching life (No. of operations) 10000
Number of Available Auxillary Contacts 4a + 4b
Approx Weight (kg) 330 350 380 400 470 500

Cubicle Dimensions and Weights
Normal Current (A) VH3 VH3D
Cubicle width (mm)
Depth (mm)
Height (mm)
Bus-section-cum-Transition panel
Width (mm)
Approx. Weight (kg)
Feeder without PT
Potential Transformer
1150      1350     1650


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