Described herein is a VI assembly that includes a VI having a stationary contact on a stationary contact potential, a moveable contact on a moveable contact potential, and a vapor shield. The stationary and moveable contacts define a contacting area. The moveable contact is moveable relative to the stationary contact along an axis of the VI. The VI assembly further includes at least one field coupler. The stationary contact and the vapor shield have a predetermined stationary contact-vapor shield capacitance with respect to each other. The moveable contact and the vapor shield have a predetermined moveable contact-vapor shield capacitance with respect to each other. The field coupler is configured such that it adds a field coupler capacitance to at least one of the stationary contact-vapor shield capacitance and the moveable contact-vapor shield capacitance to make the stationary contact-vapor shield capacitance and the moveable contact-vapor shield capacitance substantially equal.

The disclosed concept relates to vacuum interrupters having an electrically floating arc-enduring center shield component made out of an alloy of copper (Cu) and chromium (Cr), with or without additional minority alloying element or elements, and contact assemblies positioned in a vacuum envelope. In an open position, the contact assemblies include a contact gap formed there between. In accordance with the invention, contact assemblies are axially positioned such that the axial position of the contact gap aligns with a portion of the wall of the CuCr alloy-based center shield component that has a maximum thickness and outer diameter.

A vacuum bulb is provided, including a sealed chamber; two electrical contacts, which move relative to one another, the chamber including a cylindrical body of a dielectric material and closed at ends thereof by two metal covers, each of the two metal covers being connected to one of the two electrical contacts: and a dielectric coating, which covers an outer surface of the chamber, and includes at least two layers, including an overmolding layer of a synthetic material and an intermediate layer of silicone, the intermediate layer being interposed between the outer surface and the overmolding layer, the intermediate layer being discontinuous and localized on metal portions of the chamber so as to cover at least partially an outer surface of the metal portions, and the silicone includes compressible hollow bodies having a skin of a thermoplastic material.

A vacuum interrupter according to the present disclosure is configured such that a linear resistive layer and a nonlinear resistive layer are disposed so as to cover at least a part of a periphery of an insulation container, and a magnitude relationship of each resistivity is R1>R3>R2, where a resistivity of the nonlinear resistive layer less than an operating electric field is R1, a resistivity less than or equal to an impedance when a lightning impulse is applied is R2, and a resistivity of the linear resistive layer is R3.

A vacuum monitored disconnect switch includes vacuum interrupter with a high-voltage electric contactor inside a vacuum bottle, which can fail causing the vacuum switch to electrically short potentially causing extensive damage to the switch and other components. A vacuum monitor in fluid communication with the vacuum bottle includes a capacitance manometer for detecting a vacuum failure of the vacuum bottle. The capacitance manometer and associated components are powered by a current transformer (CT) that harvests power from the power line controlled by the vacuum disconnect switch. A porcelain tube in fluid communication with the interrupter vacuum bottle provides high voltage isolation between the vacuum interrupter bottle and the capacitance manometer to protect the manometer and associated electronics.