Page 668 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

so that the fuse can be removed for safe isolation purposes and ease of
maintenance.

Junction boxes

KEY POINT Below is an example of an installation where a non-fused spur has been taken
FCUs of his type are from a junction box to supply an accessory known as a ‘double-pole fused
sometimes incorrectly connection unit’. (For clarity the fuse carrier section of the FCU has not been
referred to as switched shown). It can be seen that the section of cable from the junction box to the
fused spurs. This is a FCU is what is referred to as the ‘non-fused spur’. This term is given to this
site term and should not section of cable because the cable is a separate branch from the main circuit
be used.
and is not protected by a protective device at the point of connection to the
main circuit. The cable supplying the appliance from the FCU will be normally be
of the flexible type as described earlier.

Flex to appliance Ring final circuit
(cpc left out for clarity)

Fused spur
Safely isolated circuit connection unit
Junction box

2.5 mm² flat profile cable

Ring final circuit

p Figure 11.20 Typical junction box wiring diagram with connections to terminals

SPUR
NEW COLOUR CODE

RING IN RING OUT

Junction box

p Figure 11.21 Typical junction wiring box

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