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Frequently Asked Questions About Dimmers
My dimmer makes a loud humming noise when it is switched on?
Depending on the brightness setting of the dimmer the power to the lamp may be switched at the peak point in the AC
mains supply. This sudden change in voltage can cause magnetic vibration of components within the dimmer and / or
lamps and transformers. MK dimmers are designed to minimise this noise however loads up to the maximum rating of the
product will accentuate the effect. MK Astral dimmers use newer technology that virtually eliminates available humming.
I have been told my dimmer needs extra wiring is this true?
Older buildings may not have wiring suitable for certain types of dimmers and dimming applications. In particular an
installation may be missing Earth or Neutral wiring and the services of a qualified installation engineer should always be
sought. MK Astral may require Neutral wiring in order to function with certain lamp types.
How do I know if my dimmer is overloaded, what happens?
A qualified competent installer will ensure that each dimmer is not overloaded, however in the event lamps are replaced
with types and ratings not originally intended then suitable protection is incorporated to prevent overloading. Some
products have a staged shut down and restrict power initially before fully closing the output from the dimmer under
extreme overload conditions. If a dimmer behaves in this way then first check that the total lighting load is not in excess
of the product rating. If in any doubt always consult a qualified electrician.
I have Grid Plus frontplates with dimmer modules fitted but my installer says I cannot fit more to
provide dimming on other lighting circuits, why?
Grid Plus frontplates can accommodate large numbers of switches in a small space, however dimmers dissipate larger
amounts of heat during operation and a qualified installer will need to consider the total number of dimmer modules,
the lamp load being dimmed per switch and the position on the frontplate to minimise thermal overload. By adhering to
these requirements reliable operation can be assured.
I have replaced my lamps and the new ones flicker, this wasn’t a problem with the old ones, why?
The most likely cause for lamps flickering in this situation is incompatibility of the new lamp/s with existing units or with
the dimmer fitted. If the dimmer is only specified to work with certain lamp types then compatibility issues can exist when
incorrect types are fitted. MK recommend the use of premium branded dimmable LED lamps.
I have bought an LED lamp that does not state dimmable on it or any related packaging, can I still
use it?
It can be overlooked but LED / CFL and LV halogen transformers must be of a dimmable type in order to work across the
dimming range. Use of none dimmable types is not recommended and can damage the lamp or dimmer.
Can I use both LED and LV halogen lamps on one dimmer?
No, use of different lamp types outlined in this guide are not allowed on the same dimmer circuit.
I want to have a 2 way switching circuit in my hallway / landing. Can I have dimming control from
both switch points?
Not with a conventional wired dimmer in this situation only one dimmer can be incorporated in the circuit. However, it
is possible to create this functionality using MK Echo and Astral products. Please consult a qualified installer for more
details.
*The content within this guide is correct at time of publication.