Define the followings. Insulation level, Rated short circuit breaking current, Making current, Short time rating, Impulse withstand voltage, Power frequency withstand voltage .

Define the followings.  

Insulation level,

Rated short circuit breaking current,

Making current,

Short time rating,

Impulse withstand voltage,

Power frequency withstand voltage .
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1 Answer

Answer :

Insulation level – it is the combination of rated voltage, the corresponding impulse

withstand voltage, which together characterize the insulation of the equipment as

regards its ability to withstand the electrical stresses.

Rated short circuit breaking current – it is the highest RMS value of short circuit

current which the circuit breaker is capable of breaking the circuit in safe.

Making current – it is the peak value of first loop of current of short circuit current

which the circuit breaker is capable of making at the rated voltage.

Rated making current = 2.5 times rated breaking current.

Short time rating – it is the RMS value of current that the circuit breaker can carry in

a fully closed position during a specified time.

Impulse withstand voltage – it is the amplitude of the standard voltage wave with the

insulation of equipment can withstand.

Power frequency withstand voltage – it is RMS value of alternating voltage wave of

power frequency (50 Hz) which the insulation of equipment should withstand. 

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