VB4 series medium voltage vacuum circuit-breakers with lateral operating mechanism feature the separate pole construction technique. VB4 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 VB4, 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.
Advantages
Vacuum circuit-breakers have particular advantages for use in networks where there is a high switching frequency in the working current range and/ or where a certain number of short- circuit breaking operations are expected. VB4 vacuum circuit-breakers are suitable for auto reclosing and have exceptionally high operating reliability and long life. The circuit- breakers are notable for their compact design, small dimensions together with high capacity. The operating mechanisms have a low maintenance requirement and the interrupters are maintenance- free throughout their service lives. They are well suited to all load breaking operations which occur in practice, and in particular: Short-circuit currents; Overhead lines under load and, no-load conditions; Cables under load and no-load conditions; Transformers under load and no-load conditions; Generators under load and no-load conditions; Ripple control system; Capacitor banks(also parallel switching) and Motors with starting currents above 600A.
Application
Cable control and protection Overhead control and protection Transformers and distribution substations Motor and transformer control and protection Generator control and protection Capacitor bank control and protection
Main characteristics
Service Condition
a) Air Temperature : Max Temperature :+40C; Min Temperature: -25C b)Humidity: Monthly average humidity 95%; Daily average humidity 90% c)Altitude above sea level: Max installation altitude 2500m d)No frequent violent shake