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Main switch short circuit capacity.

wessex
Some guidance please.

Three phase TN-S supply from a private 800 kVA transformer. Distribution via a 240mm2 4 core SWA approx 20m in length from a transformer mounted feed pillar and protected by 315A fuses. At the intake position 100A BS 1361 type II fuses are fitted. I was looking to install a REC 4 main switch down stream from which would be three phase distribution by 10kA rated MCB's. My question is about the suitability of the main switch and its short circuit capacity at it's point of installation with regard to prospective fault current at this point which will be greater than 16kA or do the BS 1361 afford adequate protection for the switch ? Your thoughts please.
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    Thanks for that Mike, but this is where I start to struggle.

    I take it that I need to look at cut-off current curves which for a 23kA fault gives a approx cut of 9kA peak or have I missed.

    Missed tech dept for Rec 4 today so will try tomorrow.
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    Thanks for that Mike, but this is where I start to struggle.

    I take it that I need to look at cut-off current curves which for a 23kA fault gives a approx cut of 9kA peak or have I missed.

    Missed tech dept for Rec 4 today so will try tomorrow.
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