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Junction boxes are commonly used during alterations and
additions to an installation.
Regulation 526.3 requires that every connection shall be
accessible for inspection, testing and maintenance. There are
6 exceptions to this rule. Exception (vi) is:
“Equipment complying with BS 5733 for a maintenance free
accessory and marked with the symbol
and installed in
accordance with the manufacturer’s instructions”.
BS 5733 defines a maintenance free accessory as:
“An accessory which does not require further inspection,
testing or maintenance after installation in a circuit, and which
incorporates screwless terminals and cable clamps to secure
any associated cables”.
The Electrical Safety Council Technical Manual states that “a
junction box with screw terminals must be accessible”. This
is to allow inspection of joints which could have relaxed or
loosened over time, a potential problem with screwed
terminals. So, unless provision is made for access, where
boarding, carpet or other similar covering is laid over a
junction box, it may not be considered accessible and
maintenance free terminals should be used.
This is further reinforced in Appendix 15 of the Wiring
Regulations which states “Junction boxes with screw
terminals must be accessible for inspection, testing &
maintenance or, alternatively, use maintenance-free terminals
/ connection (Regulation 526.3)”
Maintenance Free
Connections
“Junction boxes with
screw terminals must
be accessible for
inspection”.
Guide to
| Junction Boxes
9