I would like to know which section of cable should I install to power a 40m2 studio which is 54 meters from the EDF meter. In referring to several opinions and calculation methods it ranges from 2x10 to 2x25?
For this type of connection, it is always better to call on a professional electrician. Your cable length is quite large and the numbers you have been given must be based on a 15 to 45 A breaker. In fact the minimum cable cross-section between the EDF branch circuit breaker and the main distribution board terminal blocks is calculated according to the type of branch circuit breaker. For a branch circuit breaker of:
· 15 to 45A: 25² for 56 m max;
· 30 to 60A: 35² for 58 m max;
· 60 to 90A: 50² for 56 m max;
The increase of the section is explained by the risk of falls of tensions implied by such a length. For a 40m² studio the first solution should be enough.
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