Siemens SENTRON 3KF LV HRC, Руководство пользователя

Страница: 152 / 158

Glossary
3KF switch disconnectors with fuses
150
Manual, 09/2019, L1V30580914002A-01
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 that
arise in the event of a short circuit.
The characteristic for the dynamic stress is the rated peak withstand current, i.e. 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.
Switching capacity
The rating is the power that a switching device is capable of switching at the associated
rated operational voltage in accordance with the utilization category, e.g. power contactor
utilization category AC-3:37 kW at 400 V.