Toshiba HV6AS instruction manual General Description, Page

GENERAL DESCRIPTION Page 7

The Toshiba HV6AS vacuum circuit breakers described in this manual are suitable for use on systems of 4.8kV and 7.2kV voltage classes which require interrupting ratings of 16kA and 14kA respectively and a continuous current rating of 630A. The circuit breakers are intended for use in limited applications requiring small physical size and low maintenance.

These breakers are designed for fixed panel mounting and are available with upper main circuit terminals (U, MU types) or rear terminals (L, ML types).

The breakers are available as both manual and motor-operated types. Motor-operated breakers use a motor to charge the closing springs and to close the breaker upon command. Both types can be tripped electrically and also include undervoltage release.

Arc interruption is accomplished inside sealed vacuum interrupters mounted on track-resistant insulators. Vacuum interrupters use low-surge contact materials which exhibit low current chopping levels reducing switching overvoltages.

Fig. 1 and Fig. 2 illustrate and identify the major components of the circuit breakers.

COMPONENTS LEGEND:

1)Manual closing handle

2)Manual trip lever

3)On-Off indicator

4)Spring charge indicator (MU and ML only)

5)Operations counter

6)Secondary control circuit terminal block

7)Main circuit terminals

8)Auxiliary switch

9)Grounding terminal

Fig. 1 U and MU Type Circuit Breaker (Upper Main Circuit Terminals)

Fig. 2 L and ML Type Circuit Breaker (Rear Main Circuit Terminals)