A contractor has provided the single-phase electrical installation in 12 new, very small, individual commercial units. For whatever reason he provided two 6way distribution boards one appears to be for lighting and the like and the other for power, both with 30mA overall RCD protections both boards have a main switch. The tails for both boards are brought to a set of ISCOs from which he left a short tail connection for the meter. Now 4 of the units have been connected to the supply but apparently connection is being refused to the remaining units as no main switch has been provided. I guess different DNOs, different rules and indeed attitudes but I can find no reference to the need for a main switch in the DNO connection guide other than that the installation has to comply with 7671.
Ah, but not so unusual to have a different DNO approved sub contractor for the first set , with a less rigorous checking of the rules than the one making the most recent visits. I suspect the DNO and the book of rules have not changed any time recently, but rather the interpretation of what sort of installation it should be treated as, and so if it is sensible to connect or not.
After all BS7671 section 462 and thereabout could be read to indicate that there should be a single clear point of isolation at the origin, not multiple ones, but henley blocks and multiple consumer units are very common.
Thanks Mike, although it would draw into question the already connected units, either the person connecting the first batch had a bad day or the person who didn't want to connect them up had a bad day, who is wrong? Equally, presuming the installation certificate was in order, if the DNO refuse to accept it then it would suggest they are suggesting a fraudulent document has been issued?
Have new isolators supplied by the supplier with accessible terminals for the BS7671 compliant installation gone out of fashion?
Ah, but not so unusual to have a different DNO approved sub contractor for the first set , with a less rigorous checking of the rules than the one making the most recent visits. I suspect the DNO and the book of rules have not changed any time recently, but rather the interpretation of what sort of installation it should be treated as, and so if it is sensible to connect or not.
After all BS7671 section 462 and thereabout could be read to indicate that there should be a single clear point of isolation at the origin, not multiple ones, but henley blocks and multiple consumer units are very common.
Thanks Mike, although it would draw into question the already connected units, either the person connecting the first batch had a bad day or the person who didn't want to connect them up had a bad day, who is wrong? Equally, presuming the installation certificate was in order, if the DNO refuse to accept it then it would suggest they are suggesting a fraudulent document has been issued?
Have new isolators supplied by the supplier with accessible terminals for the BS7671 compliant installation gone out of fashion?
