Siemens SENTRON 3VA1, Руководство пользователя

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Applications
3.4 Use of 3VA1 molded case circuit breakers as switch disconnectors
3VA molded case circuit breakers with IEC certificate
Manual, 03/2019, A5E03603177010-03
165
3.4 Use of 3VA1 molded case circuit breakers as switch disconnectors
Switch disconnectors are deployed as:
● Disconnectors in subdistribution and final distribution boards
● Bus couplers
● Disconnectors for machine groups, e.g. as maintenance and repair breakers
● Operator control and disconnector element for cables, busbars and device groups
● Application as disconnector unit
● Application as main switches
● Isolation of small distribution systems in industrial/commercial buildings
● Disconnection of loads
Switch disconnectors are capable of switching equipment and parts of electrical installations
when they are conducting their operational current under normal operating conditions.
Switch disconnectors do not have overload or short-circuit releases. For this reason, a
molded case circuit breaker or a fuse must be installed upstream of every switch
disconnector. Refer to chapter Upstream protection of switch disconnectors (Page 170).
Compatibility of 3VA switch disconnectors and accessories
3VA1 switch disconnectors have been developed from the 3VA1 molded case circuit breaker
design. Both share the same attributes listed below:
● Sizes
● Dimensions
● Mounting options
● Procedure for installing accessories
This means that a shunt trip can trip the switch disconnectors by remote control, or that the
disconnector can be opened or closed by a side wall mounted rotary operator.