Guide to 17th Edition Consumer Units

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The Regulations have introduced new requirements regarding
socket outlets, particularly where used by ordinary persons
e.g. home owners.
The definitions for persons are important to consider when we
look at the requirements for protection of circuits supplying
socket outlets.
Regulation 411.3.3 requires that an RCD of not exceeding
30mA be provided for:
1. Socket outlets up to 20A that for general use by “ordinary
persons”.
2. Mobile equipment up to 32A that is for use outdoors.
Exceptions to 411.3.3 are permitted where:
3. Use of socket outlets is under the supervision of
someone “skilled” or “instructed”.
4. Specifically labelled or otherwise suitably identified
socket outlets provided for a particular item of
equipment.
This is a change from the 16th Edition that required only
socket outlets ‘reasonably expected’ to supply equipment
used outside the equipotential zone to have RCD protection
e.g. used for an Electric lawn mower. Now under the
requirements of the 17th edition it is likely that every socket
outlet in a domestic installation will require RCD protection
not exceeding 30mA.
This may also apply to some commercial installations, like
small offices or shops etc where there is no control on the use
of those socket outlets. Consideration should also be given to
areas where free access to socket outlets is available to the
general public e.g. airport lounges.
Socket Outlets
Guide to | 17th Edition Consumer Units 7
“Socket outlets for general use in a
domestic installation require RCD
protection not exceeding 30mA”