MK Electric Catalogue No. 49

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530
FEATURES
MK Grid Plus Dimmer Switches
incorporate the following advanced
features
l Suitable for dimming Low Voltage
Halogen lamps via suitable, fully
dimmable electronic or
wire-wound transformers.
See Table 2 for the number of
transformers allowed to be used
with each dimmer
l Can be used with good quality
mains voltage halogen lamps
incorporating GU10 bases.
Please check with lamp
manufacturer to determine
suitability
l Unidirectional current sensing.
While being used with wire-wound
transformers for low voltage
lighting, these dimmer switches
continuously monitor the drive
conditions to the transformers,
which require essentially,
bi-directional a.c. supply at their
input terminals. If, due to some
fault condition, the supply to
the wire-wound transformer is
detected to be unidirectional,
which could result in over-heating
and/or damaging the transformer,
the dimmer switches’ circuitry
automatically stops supplying the
transformer after a few cycles of
detected unidirectional supply
l Soft Start, which gradually
increases the light output from
the load over 1 to 3 seconds after
switch on. The Soft Start feature
is also particularly beneficial
when used to dim Mains Voltage
Tungsten Halogen lamps which
have inherent very high inrush
current at switch on
l Grid Plus dimmer switches which
are rated for LED load types
incorporate a minimum brightness
adjustment. This setting may
be performed without removing
any fixing screws to account for
LED load performance. Please
refer to the relevant installation
instructions on
Grid Plus Dimmer Switches
Description
Intelligent Dimmer Switches
Dimmer Switches belonging to this category employ the latest, state of the art,
micro-controller base electronic circuity and use current sensing to compute the
load conditions. These products show progressive reaction to Over-load conditions,
depending on the extent of Over-load – see Table 1. List numbers belonging to this
category are identified by the suffix letters LV, e.g. K4501 WHI LV. These Dimmer
Switches employ one pole change over switches to facilitate two way switching.
MK Grid Plus Dimmer Switches are not suitable for use with Fluorescent Lamps or
CFL Lamps.
Multiple Dimmer Installation
Load Ratings
When installing more than one dimmer in
multi-gang plates, the power rating must be
reduced to allow for heat generation.
See Table 1 page 531.
Standards and approvals
All Grid Plus dimmer switches comply with
the EC Low Voltage Directive: 73/23/EEC,
Electromagnetic Compatibility Directive 89/336/
EEC. They also comply with BS EN 60669-2-1
and BS EN 55015.
TECHNICAL SPECIFICATION
ELECTRICAL
MAINS SUPPLY VOLTAGE
230V a.c. (Nominal)
MAINS SUPPLY VOLTAGE RANGE
216V a.c. to 253V a.c.
MAINS SUPPLY FREQUENCY
50Hz
TYPE OF LOADS
Intelligent Dimmers
K4500, K4501
Fused GLS Tungsten Filament lamps to BS EN 60064:
1996 and BS EN 60432-1,2 rated at 230/240V.
Dimmable wire wound or electronic Low Voltage
Transformers of good quality. Can also be used
with good quality mains voltage halogen lamps
incorporating GU10 bases. Please check with lamp
manufacturer to determine suitability.
K4511
Is suitable for use with good quality dimmable
LED lamps (10max). Due to market variability in
LED lamp design it is advisable to check with lamp
manufacturer to determine suitability. For best
performance LED manufacturers lamps should not be
mixed on one circuit.
Note: Transformers must be suitable for dimming
leading or trailing edge dimmers.
Warning: These dimmer switches are not suitable
for use with Fluorescent Lamps or CFL Lamps.
PHYSICAL
AMBIENT OPERATING TEMPERATURE
0°C to +40°C
IP RATING
IP4X
MAX. INSTALLATION ALTITUDE
2000 metres
Grid Plus Technical
WIRING DEVICESMODULAR