Unless you have the proper electrical qualifications, experience and access to the relevant electrical standards and regulations you cannot and should not for numerous safety and legal reasons.
Are you trying to quote a design for a customer/school project/general interest or do you want someone to design a DB (distribution board?) for your business?
Refer to BS7671 2008 for the spec.
Unless you hold IEE 17th edition (part P) you will have to have it independently tested and approved before it is made live.
For a commercial, industrial or public building installation you will need to be NIC registered, which I assume you'r not otherwise you wouldn't be asking the question in the first place.
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SMDB / DB Design Proposal
Re: SMDB / DB Design Proposal
