Hager Guide To 17th Edition Consumer Units
Hager Guide To 17th Edition Consumer Units
Hager Guide To 17th Edition Consumer Units
Introduction
For well over one hundred years the Wiring Regulations have provided the rules which must be
followed to make sure that electrical installations are safe. The introduction of the 17th Edition
of the Wiring Regulations and subsequent amendments have had major implications for all
Electrical Contractors, Designers and Consultants.
Several regulations have an impact upon circuit design, consumer unit layout and even the construction of the consumer unit
itself.
This guide will help you understand the new Wiring Regulations and current Building Regulations, providing the necessary
facts to construct compliant installations including Consumer Units.
If after reading this guide you would like to find out further information regarding the new regulations Hager offer tailored
training courses. If you are interested in registering interest in attending one of these courses please visit www.hager.co.uk
Contents
Building Regulations
Page 5
Page 6
Socket Outlets
Page 9
Page 10
Special locations
Page 12
Other Considerations
Page 14
Page 16
Page 18
Page 24
Page 25
While the author believes that the information and guidance given in this document is correct, all parties must rely upon their own skill and
judgement when making use of it. The author does not assume any liability to anyone for loss or damage caused by any error or omission in
the work, whether such error or omission is the result of negligence or any other cause. Any and all such liability is disclaimed.
Guide to | 17th Edition Consumer Units
Building Regulations
Since 2005 the Building regulations for England and Wales
have made direct reference to electrical installations,
increasing the influence on how electrical equipment is
installed in buildings.
Part P of the building regulations relates to the electrical
safety in dwellings. The approved document prescribes that
switches, sockets and consumer units in new dwellings
should be easy to reach, in accordance with Part M of the
building regulations.
Approved Document M recommends that in new dwellings,
switches, sockets and other equipment should be located
between 450mm and 1200mm from finished floor level, it
also suggests that consumer units are mounted so that the
switches are between 1350mm and 1450mm above floor
level.
Height of
between
1350mm and
1450mm from
floor level
In the case of multi-row consumer units, the bottom row of
switches should be between 1350 and 1450mm so that they
are out of reach of young children.
Depending on the layout of the dwelling and position of the
consumer unit, a flush consumer unit may be considered.
Door
The consumer
unit enclosure
should be made of
non-combustible
material
Cover
1mm
1mm
2.5mm
2.5mm
2.5mm
Openings around
cable entry should
be minimized, use
of trunking is one
option
Other Enclosures
As previously stated, regulation 421.1.201 includes for
consumer units AND similar switchgear. In a larger dwelling
there may be a requirement for a 3 phase supply. The
distribution board in this instance would be required to meet
the same non-combustibility requirements as a single phase
consumer unit.
It is important the specifier obtains information from the
manufacturer of the 3 phase TP&N enclosure that this
requirement is satisfied. It may not simply be the case of
using a TP&N enclosure which is normally used in commercial
applications as there may be some plastic components which
will not meet the non-combustable criteria.
Socket Outlets
The Regulations prescribe requirements regarding the use
and protection of socket outlets,
10
Stud Partition
11
12
Saunas
Swimming pools
13
Other Considerations
There are additional Regulations and Codes of Practice that
need to be considered during the design of an installation.
These will affect the choice of consumer unit.
Division of Installation
Section 314 calls for the installation to be so divided to:
14
15
16
The RCD should serve only the circuit supplying the fire
detection and alarm system, or
The RCD protection of the fire detection and alarm system
circuit should operate independently of any RCD
protection for circuits supplying socket outlets or portable
equipment.
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A consumer unit with a 30mA RCD main switch is likely to be unsuitable for the following reasons:
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Conclusions
It is clear that domestic installations conforming to the 17th
Edition of the Wiring Regulations are likely to require
increased use of RCD (Residual Current Devices) and careful
consideration from designers and installers is required to
meet the requirements of the regulations.
Training Courses
Hager runs an on-going programme of training courses
targeted towards wholesale trade partners, specification
engineers and installation contractors.
Hager training courses satisfy the Continuing Professional
Development - CPD, requirements of the major engineering
institutions.
To register yourself on to one of our training courses in your
area please visit our website www.hager.co.uk and click on
the services section.
24
Consumer Unit
MCB
RCBO
25
Hager Ltd.
Internal Sales Hotline: 01952 675612
Hortonwood 50
Internal Sales Faxline: 01952 675645
Telford
Shropshire
Technical Helpline: 01952 675689
TF1 7FT
Technical Faxline: 01952 675557
www.hager.co.uk
technical@hager.co.uk
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