VD4 vacuum circuit breakers have been designed for indoor use and air insulated switchboards.
Their switching capacity is sufficient to handle any conditions arising from switching of equipment and system components under normal operating and fault conditions, particularly short-circuits, within the parameters of their technical data. The vacuum circuit-breakers of type VD4, designed in column form, can be supplied both as individual units for fixed installation and mounted on chassis. Vacuum circuit-breakers are characterized by their simple and robust construction. They have a long life expectancy. There is no adverse effect on the vacuum, even from frequent switching of operating and short-circuit currents.