Retrofitting VCB for GCB

Recommendation to replace the existing GCBs with new VCBs in order to ensure the safe and reliable operation of your switchgear.

Features of Retrofit VCB

Outstanding reliability

  • The highly reliable operating mechanism is incorporated in the Retrofit VCB. This operating mechanism is used in Mitsubishi’s latest VCBs.
  • Self-cooling VCBs that do not require a fan to be mounted on the panel. Available in a wide range, from rated current of 1,250 to 3,150A.
  • Compliant with IEC 62271-100-2012 and has passed type tests for classes M2, E1 and C2, which represent the highest levels of quality.

Saving running cost

  • By application of VCB, no need to treat the SF6 gas and to carry out the overhaul with dismantle work for inspection and cleaning inside of the tank.
  • The mechanical parts are coated with a long-life grease that contributes to the prevention of oxidation degradation and oilless bearings has been adopted for the bearing section of latch, thus extending the lubrication cycle to mechanical parts from three to six years and reducing the time required for maintenance.

Environmental friendly

  • No use of SF6 gas of having high global warming potential.
  • No use of the six hazardous substances (mercury, cadmium, lead, hexavalent chromium, PBB and PBDE), a measure that exceeds the requirements of RoHS standards. One example is use of a rust-proofing treatment for small parts such as pins and screws that is free of hexavalent chromium, a substance known to contaminate soil.

Saving replacement work

  • Interface with the existing panel between GCB and Retrofit VCB is same.
  • No modification is required.⇒No need long shutdown.

Ratings

Type 10-VPR-40D(GV)
CR suppressor（*1） for sub code name C,L（*2） mounted none
CR suppressor（*1） for sub code name S（*2） none
Closing operating mechanism Motor-spring charged mechanism
Standards（*3） IEC62271-100- 2012
Rated voltage (kV) 12
Rated normal current
(A)		 1,250 1,250 2,000 3,150
Rated normal current(A) In the case of ambient temperature 50℃ 1,000 1,000 1,600 2,700
Rated frequency (Hz) 50/60
Rated short-circuit breaking current (kA) 40
Rated short-circuit Making current (kA) (Peak) 104
Rated short-time withstand current (kA) 40 (3s)
Rated opening time (s) 0.03
Rated breaking time (cycles) 3
Rated withstand voltage (kV) Power frequency 28 36
Rated withstand voltage (kV) Lightning impulse 75 95
Type test class（*4） Mechanical M2
Type test class（*4） Electrical E1
Type test class（*4） Small capacitive current switching C2
Rated operating sequence O-3min-CO-3min-CO
CO-15s-CO
O-0.3s-CO-1min-CO
No-load closing time(s) 0.1
Closing operating/control current (A)（*5） Motor 1.2 (motor charging time: 6s)
Closing operating/control current (A)（*5） Control current (Closing coil) 3.5
Tripping device Shunt tripping coil (STC)
Opening control current (A) (STC coil)（*5） 4
Auxiliary switch 5a5b
Operating counter (Mechanical) Standard equipment
Mass (kg) for sub code name C,L（*2） 250 225 265 370
Mass (kg) for sub code name S（*2） - 225 255 350
Type of interchangeable GCB 10-SFG-40
  1. *1 CR suppressor is a device to absorb the surge generated by switching.
  2. *2 Sub code name C : mounted CR suppressor for power stations.
    Sub code name L : none CR suppressor for power stations.
    Sub code name S : none CR suppressor for transformer substations .
  3. *3 IEC : International standards, IEC 62271-100-2012.
  4. *4 Type test class described in IEC 62271-100-2012.
  5. *5 Closing operation/control current and opening control current show the value of 110V DC.

VCB & GCB Comparison

Comparison of Life of VCB & GCB

List of open and close expected life
Unit Item Retrofit VCB GCB
Mechanical life Number of operations 10,000 times
Electrical life Short circuit breaking 30 times 10 times
Load current breaking 10,000 times
Small current (less than 100 A) breaking 10,000 times 3,000 times
Life of whole circuit breaker Number of operations 10,000 times
  • NOTE : The above switching number of time is the actual capacity checked in the short-term continuous switching test, and does not guarantee the life for a long period of time.
  • NOTE : Perform the maintenance and inspection according to the standard of the inspection manual to keep the service life.

Comparison of Scheduled Maintenance

List of scheduled maintenance
Periodic Inspection Retrofit VCB GCB
General inspection (Every 3 years) Man-hours: 2 Hr × 2 men Man-hours: 4 Hr × 2 men
・Visual check and cleaning
・Check of insulation resistance
・Lubrication of primary junctions		 ・Visual check and cleaning
・Check of insulation resistance
・Lubrication of mechanism, primary junctions
・Operation Test
Detailed inspection (Every 6 years) Man-hours: 5 Hr × 2 men Man-hours: 10 Hr × 2 men
・Check of vacuum pressure
・Lubrication of mechanism
・Operation test		 ・Inspection and adjustment of Breaking part
・Operation test
Replacement of breaking part When the number of operations exceeds the values below, the VI should be replaced. When the number of operations exceeds the values below, main contacts and arcing contacts should be replaced.
・Load current: 10,000 times (replacement of entire VCB)
・Short-circuit current: 30 times		 ・Load current: 1,000 times
・Short-circuit current 10 times

Comparison of Structure

List of structure
Unit or Part Retrofit VCB GCB
Control circuit Same as GCB Stored energy motor operation
Interlocking When moving CB inside panel, closing operation cannot be performed. When CB is closed, it cannot be moved inside panel.
Insulation Epoxy-resin molding for main conductors and BMC (Bulk Mold Compound) for separation of VI's. Epoxy-resin molding Insulation by SF6
Drawout mechanism Same as GCB Withdrawn by pulling of handle.
Truck Position switch, automatic safety shutters.
Primary junction Tulip type connector, self-coupling.
Secondary junction Manual-coupling
Ext. aux-switch Mechanically linked operating mechanism.

Outline and Dimensions

Dimensions

Rated normal current(A) Dimensions(mm)
A B C H J K M N
common for sub code C, L for sub code S for sub code C, L for sub code S
1,250/2,000 200 605 680 985 385 350 883 783 689 589
3,150 250 755 830 1040 400 400

If consider using this retrofit VCB, please contact us to confirm any interference with the existing Switchgear.
In that case, please inform the serial number of the existing GCB and existing Switchgear.