RCB v.s. Main fuse rating.

5 Apr 2008
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United Kingdom
My incoming supply fuse has been uprated to 100A. As well as one CU with a 100A RCD, there is also two separate 63A RCDs each with their own fused switch for outside services. These RCDs are connected in parallel with the CU, directly to the output side of the meter. Is their rating OK, given that their only protection from the power station is the supplier's 100A fuse?
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None on one of them, fuse is 40 A. Other has a 60A fuse and then at the receiving end, four very early mcbs [ the type that were fitted in CU fuse carriers] two at 32A and two at 6A.
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