Choice of light dimmers

Light dimmer technology should be adapted to
the lamp and luminaire technology:
incandescent lamps: dimmer switches with
triac, voltage variation by varying the firing angle,
electronic ballasts with variable voltage:  dimmer
switches with triac, voltage variation by varying
the firing angle (this technology is on the way out),
electronic ballasts that can be controlled by a
1-10 V signal,

dimmer switches with automatic matching to
ELV transformers or electronic converters.
Light dimmers supply the lamps gradually at
switch-on, and thus reduce high inrush currents.
Their use therefore avoids any derating of control
and protection devices and oversizing of
conductors.
Precautions should still be taken to ensure the
reliability of installations and it is especially
necessary to check that no overload is imposed
on electronic devices, for example by using the
information provided by switchgear