Short circuit current vs. bolted fault current

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retcec said:
Are bolted fault current and short circuit current regarded the same, i.e., for calculating incident energy?
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Comparing apples to oranges.
This is the way that I have looked at it:
I may assume that what you may be referring to as short circuit current is the "available short circuit current."
Then the actual current which flows into a fault is to be determined by the type of fault going from a common arcing fault which would result in a current which is dependent upon the impedane of the arc itself to the "bolted fault" where the fault current is the maximum available and would be anly limited by the conductor and the impedance of the circuit.
The only other consideration is motor contribution to the available fault current.
 
The IEEE1584 formulas are based on the short circuit amps that would flow through a bolted 3-phase fault.
These IEEE1584 determines a 'calculated arcing fault' current, based on several factors and calculations, which is used to determine the incident energy.
 
retcec said:
Are bolted fault current and short circuit current regarded the same, i.e., for calculating incident energy?
Click to expand...

Another way of looking at the term "short circuit current" is that it is a generic term with specialized terms to further identify what is meant. For example:

Bolted fault current - a short circuit current that produces maximum fault current
Arcing fault current - a short circuit current that contains resistance which makes it lower than a bolted fault current and arcs in the air
Available fault current - the short circuit current that the utility company is capable of supplying
Infinite bus fault current - the short circuit current that would be available from the utility with infinite sources behind it

The arcing fault current at the equipment being analyzed would be used for the incident energy.
 
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