ETAP Short circuit calculation

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Please see the attached.

480V MCC is connected to 480 V Switchgear through 6-1/C 750 MCM cable. Considering TIE for 480V Switchgear closed; both switchgear, MCC buses are under a fault condition; max circuit current coming for switchgear is 115 KA and for MCC coming as 32 KA.

1. How to limit the short circuit current for the switchgear to 85 KA?

2. When the MCC is connected to the switchgear through the cable, Why short-circuit current of the MCC coming as 32 KA only? Why not it is as high as 115 KA, which was connected to switchgear?
 

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Yes, the cable length is affecting the Short circuit current. 100' is giving around 65 KA.

How to limit the short circuit current for the 480V switchgear to 85 KA, as the switchgear is rated for 85 KA. It was connected from 13.8 KV switchgear and 3333KVA T/F. This is under the tiebreaker closed condition. When the tiebreaker is open it is limited to 65 KA only, which is fine.

Thank you.
 
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