5
Aspirante pumped electric
electrical installation must be effectively
connected electrically to all exposed metal
parts of other appliances and services in
the room in which the shower is to be
installed, to conform to current IEE
regulations.
5.1
All exposed metallic parts in the bathroom
must be bonded together using a cable of
at least 4mm
2
cross sectional area. These
parts include metal baths, radiators, water
pipes, taps and waste fittings.
6
For close circuit protection DO NOT use a
rewireable fuse. Instead use a suitably
rated miniature circuit breaker or cartridge
fuse
(see table A)
.
6.1
In the interest of electrical safety a 30mA
residual current device (RCD) should be
installed in all electric and pumped
shower circuits. This may be part of the
consumer unit or a separate unit.
7
A 45 amp double pole isolating switch
with a minimum contact gap of 3mm in
both poles must be incorporated in the
circuit.
7.1
It must have a mechanical indicator
showing when the switch is in the OFF
position, and the wiring must be
connected to the switch without the use
of a plug or socket outlet.
7.2
The switch must be accessible and clearly
identifiable, but out of reach of a person
using a fixed bath or shower, except for
the cord of a cord operated switch, and
should be placed so that it is not possible
to touch the switch body while standing
in a bath or shower cubicle. It should be
readily accessible to switch off after using
the shower.
8
Where shower cubicles are located in any
rooms other than bathrooms, all socket
outlets in those rooms must be protected
by a 30mA RCD.
9
To obtain full advantage of the power
provided by the shower, use the shortest
cable route possible from the consumer
unit to the shower.
9.1
The current carrying capacity of the cable
must be at least that of the shower circuit
protection
(see table B)
.
9.2
It is also necessary to satisfy the
disconnection time and thermal
constraints which means that for any
given combination of current demand,
voltage drop and cable size, there is a
maximum permissible circuit length.
10
The shower circuit should be separated
from other circuits by at least twice the
diameter of the cable or conduit.
10.1
The current rating will be reduced if the
cabling is bunched with others,
surrounded by thermal loft or wall
insulation or placed in areas where the
ambient temperature is above 30°C.
Under these conditions, derating factors
apply and it is necessary to select a larger
cable size.
10.2
In the majority of installations, the cable
will unavoidably be placed in one or more
of the above conditions. This being so, it
is strongly recommended to use a
minimum of 10mm cabling throughout
the shower installation.
10.3
It is essential that individual site conditions
are assessed by a competent electrician to
determine correct cable size and
permissible circuit length.
Twin and earth PVC insulated cable
CURRENT CARRYING CAPACITY
clipped direct or
installed in an in conduit
buried in a non
insulated wall or trunking
insulated wall
6mm
2
6mm
2
6mm
2
32A
38A
46A
10mm
2
10mm
2
10mm
2
43A
52A
63A
16mm
2
16mm
2
16mm
2
57A
69A
85A
Note: Cable selection is dependent
on derating factors
Table B
