With more and more in the home being powered off DC (Direct Current) supplies, e.g. Battery & Solar Panels, then wouldn't it be more economical to consider extending the regulations to cover DC in the home avoiding the need for transformers?
For example, this is particularly appropriate now that lighting is dominated by LED.
PeterRT:
Unfortunately I do not have a copy of the current regulations as they are very expensive for the occasional read for interest.
Yes, for DC in the home I would expect to see a standard voltage, maximum power, standard plugs and sockets etc so I can go to a specialist technician and get it done.
Peter.
BS 7671 is in a good place for DC systems, but product standards for household products are not yet up to speed.
Standard voltages for AC are not stated in BS 7671 … they are in BS EN 60038 CENELEC Standard Voltages. This standard has the following preferred voltages for DC equipment below 750 V DC: 6, 12, 24, 36, 48, 60, 72, 92, 110, 220, 440. However, the standard does not have preferred values for DC distribution. In fact, it only specifies (Table 1) AC distribution in terms of three-phase star/delta or three-phase delta.
In terms of electrical accessories, these are largely dependent on product standards, which are yet to be developed. This IET publication contains a commentary on the suitability of common standards for protective devices, accessories, etc., for use with DC:
PeterRT:
Unfortunately I do not have a copy of the current regulations as they are very expensive for the occasional read for interest.
Yes, for DC in the home I would expect to see a standard voltage, maximum power, standard plugs and sockets etc so I can go to a specialist technician and get it done.
Peter.
BS 7671 is in a good place for DC systems, but product standards for household products are not yet up to speed.
Standard voltages for AC are not stated in BS 7671 … they are in BS EN 60038 CENELEC Standard Voltages. This standard has the following preferred voltages for DC equipment below 750 V DC: 6, 12, 24, 36, 48, 60, 72, 92, 110, 220, 440. However, the standard does not have preferred values for DC distribution. In fact, it only specifies (Table 1) AC distribution in terms of three-phase star/delta or three-phase delta.
In terms of electrical accessories, these are largely dependent on product standards, which are yet to be developed. This IET publication contains a commentary on the suitability of common standards for protective devices, accessories, etc., for use with DC:
