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VS 12 is a Three Phase Outdoor, Porcelain Clad Vacuum Circuit Breaker, with a continuous current carrying capacity of upto 1250A. It consists mainly of the Three Phase Poles, mounted on a strong Box Section Steel Frame, under which is mounted the Operating Mechanism. The whole Breaker is supported from the ground by a steel structure, designed to give the minimum physical clearance to ground specified by the buyer. The Phase Poles contain the Vacuum Interrupter, and immediately below the contact Compression Spring, the whole of this assembly being connected to a Counter Shaft by an insulated link housed within the porcelain. The counter shaft is in turn driven by the stored energy of the spring charged mechanism. The mechanism has provision for holding one closing operation in store at a time. A well designed latch ensures positive latching and a very light, and fail proof, tripping.


The input and output leads are connected to the VCB through Integral Connector Pads, facing opposite directions. Extensive finning of the Connector Pads ensures very low temperature rise. The Porcelains are generously dimensioned for ensuring a high safety factor, for both Electrical and Mechanical loadings. The Box Section main frame forms a stiff beam, against both bending and torsion caused by the heavy contact loads, and high impacts inherent in VCB technology. The Operating Mechanism offers, besides the usual Manual Close and Emergency Trip facilities, also solenoid coils for remote operation and for operation with Protective Relays. While the closing spring is manually charged in the standard execution, it is possible to outfit an universal electric drive, as an option. A positively driven auxiliary swtich has an adequate number of potential free contacts for buyer's use. Mechanically driven Flags are provided for showing the operating mode of the Breaker (i.e. On/Off), and the status of the closing springs (i.e.Free/Charged). The mechanism housing, as well as the active Porcelain Clad Poles are protected to C1 IP55.


VS 12 has been type tested at CPRI, and the Division of High Voltage Engineering, Anna University, Madras. All routine tests of Clause 3 of IS 2516 Part IV, Section 2 (equivalent of Dec 76) are carried out on each breaker. Besides, each breaker undergoes routine check for soundness of execution, by applying atleast 200 closing and tripping operations before despatch. This check, which is over and above the specifications of the IS, ensures a quality product, and guarantees performance without any problems when installed.


Application Standard               : IS 2516.
Voltage                            : 12kV
Current (Max)                      : P 1250A
Making current Peak                : 66.5kA
Breaking Current RMS               : 26.3kA
Short Time current (3 Sec.)        : 26.3kA
Basic Impulse Level                : 75kVp.
1 Min. a.c. Test level             : 35kV.

As the design and manufacture of our equipment are subject to constant improvement, the product supplied may differ in certain details from the specifications and illustrations.

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