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sollysta Wiring Accessories Guide
5
Lighting
Light switches & load type
Electrical equipment selected shall have suitable
characteristics appropriate to the values and conditions on
which the design of the electrical installation is based.
These conditions include voltage, current, frequency, power,
environmental conditions and prevention of harmful effects.
The designer needs to consider the types of loads which are
to be controlled taking into consideration any instructions
from the manufacturer. Fluorescent loads are commonplace,
particularly in commercial installations.
BS EN 60669-1 is the standard for switches for household
and similar fixed-electrical installations. The manufacturer is
required to declare and mark the switch with the rated
current in amperes (A) or rated fluorescent load in amperes
(AX). Hence a switched marked AX will not require derating
when used with fluorescent loads.
Dimming
Rarely in the modern home is lighting controlled purely by
switching on and off, but dimming is required. Also a very
popular light fitting is the downlighter which comes in various
different forms, (i.e. mains or ELV).
The dimmer switch is an electronic device that controls the
energy delivered to the light fitting and hence controls its’
light output. Installers need to select the correct dimmer
switch especially if ELV lights are being used with dimmable
transformers. The selection of the most up to date devices
with leading edge technology means that such a dimmer can
operate both ELV or mains voltage lights and not cause any
loss of performance.
Often dimmers, when used with 2-way switching will only dim
from one position, with the secondary position just turning on
& off. Today dimmer switches are available offering master/
slave capability so dimming and switching is available from
more than one position.
“ Ensure correct dimmers are used for the
type of load ”.