Siemens Sentron 3VA, Руководство пользователя

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Glossary
3VA molded case circuit breakers with UL and IEC certification
Manual, 01/2019, L1V30435333-01
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Short-circuit strength
This is the resistivity of a switching device in the closed state, along with its components
(e.g. trip units), or a complete switchboard to the electrodynamic and thermal stresses which
arise in the event of a short circuit.
The characteristic for the dynamic stress is the rated peak withstand current, which is the
maximum instantaneous value of the short-circuit current.
The characteristic for the thermal stress of the short-circuit current is the root-mean-square
value of the short-circuit current throughout its duration.
Tripping current of overload release
The current value at which a trip unit trips within a specified time.
Tripping current, ground fault
When the ground fault current reaches or exceeds this limit value, the ground-fault
protection, for example, of a molded case circuit breaker, is tripped.
Tripping current, instantaneous
When this current limit is exceeded, the circuit breaker trips instantaneously.
Tripping current, overload
When this uninterrupted current limit is exceeded within a predefined time period, the circuit
breaker trips (inverse-time delayed tripping).
Tripping current, short-time delayed
When this current limit is exceeded, the circuit breaker trips after a predefined time delay.
Tripping time
Period of time from the instant of commencement of trip command output to the moment at
which the command becomes irrevocable (timing concept for the tripping of circuit breakers).