Describe the detailed design calculations for selecting the size of a busbar, switchgear, type-2 coordination, and discrimination study.

Question

Accepted Answer

Explanation of design calculations for selecting busbar size, switchgear, type-2 coordination, and discrimination study.

Busbar size selection based on current carrying capacity and voltage drop
Switchgear selection based on fault level and load current
Type-2 coordination ensures proper operation of protective devices during a fault
Discrimination study ensures that only the faulty section of the system is isolated during a fault
Calculation of short circuit current and fault level is necessary for switchgear and coordination selection

Accepted Answer

All the components to be checked and insured for healthiness before making it ON in type 2.
Bus bar selected on the level of  fault current  in kA. The bus size depend on the 1 Fault level.  and it's derating factors - Enclosure, Temperature Rise, Proximity factor 
The selected bus bar size should have mechanical strength to withstand the bending moment develop during short circuit.

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Describe the detailed design calculations for selecting the size of a busbar, switchgear, type-2 coordination, and discrimination study.

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