3
6
9
2
5
8
4
7
Grid Plus Intelligent
Dimmer Switch
These Grid dimmers comply with both
BS EN 60669-2-1 & BS EN 55015
Please keep this leaflet for future
reference
SAFETY INSTRUCTIONS
• This product must be installed by a competent person
in accordance with the current IEE Wiring regulations
(BS7671) and Building Regulations.
If in any doubt, consult a qualified electrician.
• To prevent electrocution, do not work on any appliance
live. Turn off mains electricity supply before
commencing work.
• An earth terminal is provided on the Grid mounting
frame. This must always be connected to earth.
• To prevent fire hazard do not exceed the related load
specified for the product.
• The minimum box depth required is 40mm.
• Dimmer switches must not be used in bathrooms,
washrooms or any location subject to splashes of water
condensation or dampness.
48366 PL Ed. 1
GENERAL INFORMATION
• The control knob has a push on/push off action.
Rotation of the knob will vary the light setting.
• The terms one-way and two-way switching refer to the
mode of switching required in an installation.
• One-way switching is used in installations that require
just one switch to control a circuit. (i.e. one light that is
either on or off.) See Fig. 1.
• Two-way switching is applied to installations where a
circuit is often controlled by two switches, e.g.
controlling a light circuit from two switches located
some distance apart, one switch at one end of the room
and another switch at the other end.
• MK dimmers have two-way switching, which allows their
use in any application.
• In a two-way installation as shown in Fig. 2, just one
dimmer must be used. A standard 2-way switch must be
used in the other position.
• As long as the rotary control knob is not turned, when
pressed, the dimmer will switch on at the previously set
light level. The light level can then of course be
immediately adjusted by turning the control knob, if
required.
• In a two-way circuit, if the 2-way switch is used to
operate the circuit, the light level will only ever return at
the last used light setting. Light levels can only ever be
adjusted by using the dimmer.
• To avoid damage, do not operate the dimmer outside
its maximum and minimum wattage, or volt/ampere
limits. The limits are shown on the rear of the dimmer,
on packaging and in the Specification section below.
• Please note, it is also necessary to de-rate the dimmers
when used in multiple installations. Please see chart “B”
for the de-rated values.
• The dimmers should not be installed where an ambient
temperature is outside the 0ºC & 40ºC limits.
NOTE:
It is normal for the front of the dimmer to become
quite warm in use, the temperature reached being
dependent upon the lamp load and the ambient
temperature.
• MK dimmers employ the latest technology, using micro-
controlled based circuitry to provide the features
described in the following section.
PRODUCT FEATURES
NOTE;
- For correct operation, it is very important that the
total load MUST NOT be less than the minimum
power/load rating AND MUST NOT be greater than the
maximum power/load rating marked on the dimmer. This
rating is shown in Watts (W) & Volt/Amps (VA) on the back
of each dimmer.
Soft Start When the dimmer is switched on, the brightness
of the lights will be gradually increased over a period of 1
to 3 seconds until a pre-selected level (set by the control
knob, is attained.
This feature alone will help to greatly extend the life
expectancy of filament lamps, by avoiding the initial power
surge.
Overload Protection If any of the dimmers are overloaded,
the output to the lamp(s) will be automatically reduced to
provide protection against damage to the dimmer and to
the installation. An Intelligent Power Monitoring System
(IPMS) is used to provide protection from overload by
reducing power levels to the load(s) in stages according to
the severity of the overload, as follows: - (Note; The first
figures given are the approximate load on the dimmer as a
percentage of its maximum rating.)
Up to 125 Load will receive maximum power
continuously.
› 130 to 200 Output load will be reduced to the minimum
setting after a delay of approximately 20
seconds after switch on.
› 200 Output will be disabled (load will switch off)
almost instantaneously after switch on.
Normal operation will resume after the dimmer is switched
off and turned back on, with the load adjusted to be within
its maximum and minimum ratings.
Compatibility with Low Voltage Lighting Systems
One form of Low Voltage Lighting System comprises a
good quality wire wound step down transformer for Low
Voltage Lighting loaded with suitable Low Voltage
Tungsten Halogen lamps(s). Another form comprises a fully
dimmable Electronic Transformer, specifically designed for
dimming using phase delay, phase-cut-on or leading edge
type of dimmer, loaded with suitable Low Voltage
Tungsten Halogen lamp(s).
The dimmers are designed to work with a large number of
fully dimmable, good quality, Wire Wound as well as
Electronic Low Voltage Lighting Transformers, which are
recommended for use with phase delay, or leading edge
type dimmers. DO NOT
use transformers that are only
suitable for use with phase cut, phase cut-off, or trailing
edge type dimmers.
So as not to compromise system safety, MK recommend
that transformers have built in thermal protection and have
over-current protection on both primary and secondary
circuits. The LV system must comply with the EMC directive
and carry the CE marking. The total transformer load on
the dimmer (obtained by adding together the load rating
of each transformer) must be within the minimum and
maximum load rating W/VA of the dimmer.
In addition, transformers MUST be loaded correctly and
they must provide correct loading to the dimmer, within its
specified minimum and maximum Power/Load ratings.
For optimum performance of the dimmer, load each
transformer with lamp(s) so that the total load on each
transformer is between 75 - 100% of its rated load. (e.g.
load a transformer rated at 25 to 105W/VA with lamps, so
that their total wattage adds up to 80 to 105 watts.Note:
Some transformers for low voltage lighting have input
circuits which, when used with phase delay types of
dimmer, result in very high peak power pulses in the
dimmer. To avoid overloading and possible malfunctioning
of the dimmer, do not connect more than the maximum
number of transformers specified below, to any one
dimmer.
Up to 300W/240VA dimmers - Max. 4 transformers.
Over 300W/240VA dimmers - Max. 5 transformers.
Compatibility with Mains Voltage Halogen Lamps
The soft start feature incorporated in this range of dimmers
makes them ideally suited to drive mains voltage halogen
lamps, which have inherently high inrush currents at switch
on. By using a soft start with this type of load(s), not only is
the dimmer protected against premature failure but the
lamp(s) load also benefits from prolonged life due to
limitation of the life shortening high inrush currents at
switch on.
Failure to comply with the pre-requisites given above could
compromise System Safety.
None of the MK Grid dimmers are suitable for use with
fluorescent lighting, which includes energy saving lamps.
SPECIFICATION
Nominal mains supply voltage .............. 230 volts a.c.
Max. acceptable mains fluctuation ........ 216 to 253V a.c.
Mains frequency ..................................... 50Hz ± 3Hz
Ambient temperature range .................. 0°C to 40°C
The Grid dimmers can be used with the following: -
• Fused GLS Tungsten Filament lamps to BS EN 60064,
rated at 230/240 volts only.
• Mains rated Halogen lamps
• Wire wound Low Voltage transformer(s) of good quality,
either laminated or toroidal.
• Fully dimmable Electronic Transformer(s) suitable for
mains input voltage range specified above, used in
conjunction with Low Voltage Halogen lamp(s).
NOTE: Transformers must be suitable for dimming; using
the phase delay, not phase cut type of dimmers.
Under no circumstances should the minimum/ maximum
ratings given in table “A” be exceeded.
1. On front plates mounting multiple dimmers, the minimum
/ maximum W and VA ratings given are for each dimmer.
2. The minimum load of the transformer should not be less
than the Min. Power/Load Rating of the dimmer, even if
the transformer has a lower Min. power/Load rating (e.g.
20W or VA).
3. If the transformer is loaded with more than one lamp to
achieve the minimum load in accordance with the Min.
Power/Load Rating, then on failure of one or more of the
lamps, the total load may fall below the Min. Power/Load
Rating of the dimmer, which could result in the system not
functioning correctly.
1
module 40 220 40 180 3
2
module 60 400 60 320 5
Size of
dimmer
Power/Load
rating With
mains Tungsten
GLS lamps
Power/Load rating
With mains Tungsten
Halogen Lamps and
LV Transformers
Max. No.
Transfor-
mers per
dimmer
Min.
Wattage
Max.
Wattage
Min.
W or VA
Max.
W or VA
Table A
48366PL Ed1 21/11/05 1:45 pm Page 1
12
15
18
11
14
17
10
13
16
INSTALLING THE DIMMER IN A ONE-WAY SITUATION
1. Make sure that previous sections of these instructions
are fully understood prior to installing the dimmer.
2. Please note; the colour codes used in the UK prior to
April 2004 are as follows: -
Live = RED Neutral = BLACK
In all other areas of the EU, as well as new build
installations in the UK after April 2004, the colour codes
used are: -
Live = BROWN Neutral = BLUE
The first colour indicated in the following text will be that
used prior to April 2004. The second colour, shown in
brackets, is the colour used after April 2004.
3. Ensure the mounting box is firmly fixed to the wall.
4. If there are fixing lugs at the top and bottom of the box,
it may be necessary to bend them back, so as to clear
the Grid frame.
5. If replacing an existing dimmer or switch, always take
careful note of the cables and old terminal descriptions
before removing the old switch. This should make it far
easier to install the new dimmer.
6. Ensure the correct box depth is being used and mount
the MK Grid Plus mounting frame to the box in the
normal way.
7. To ensure good thermal management and therefore
reliability, please be sure to comply with the following
advice: -
i) In multi row installations, the dimmers should be
mounted in the lower rows wherever possible. This
will ensure the dimmer will operate more reliably.
ii) Do not mount dimmers one above the other in
adjacent rows or side by side in adjacent columns.
Stagger the position of the dimmers as much as
possible.
iii) Do not exceed the maximum Load rating of any
dimmer, as printed on the back of the dimmer.
8. Screw the Grid mounting frame to the back box. Do
not tighten the screws at this stage.
9. Prior to installation, remove the rotary control knob by
gently pulling it away from the body of the dimmer.
10. As stated above, a one-way installation is where simple
on or off switching and dimming of one lamp from one
position is required.
11. Strip back the outer cable sheath of the cable and trim
the inner cables to the appropriate length.
12. Carefully strip the inner cable insulation to expose
8mm of the conductor.
13. All live conductors should have red (brown) sleeving.
This is achieved by fitting a short length of sleeving
over the end of any lead that has black (blue)
insulation.
14. Ensure each wire is connected to the appropriate
terminal, as shown in the typical diagram - See Fig. 1.
15. An earth lead must be installed and connected to the
terminal in the mounting box, with an additional short
length of cable joining the frame to the box. A length
of green/yellow sleeve must be fitted over all earth
leads.
16. Carefully push the wired unit back into the Grid
mounting frame, until the latches have fully engaged
and the module is secure (as shown in Fig. 3). Ensure
cables are not trapped or pinched.
17. When installing a 2 module dimmer, the Blank Insert
supplied with the dimmer has to be clipped into the
Grid frame after first installing the dimmer. The
positional relationship is dependent on the normal
spacing of the Grid modules on the frame. See
instructions supplied with the Grid system.
18. It is possible to remove a module by placing the blade
of a screwdriver in the top clip, where it engages with
the frame and carefully levering it out. See Fig. 4.
19. With 2 module Dimmers, the Blank Insert will need to
be removed first.
20. When all the modules have been fitted, the Grid
mounting frame can be adjusted to set the front plate
squarely. Adjust the Grid frame by hand before
tightening the frame fixing screws.
21. Locate the front plate and fit it to the Grid frame using
the Front plate fixing screws. Do not over tighten the
screws so as to prevent damage or distortion to the
front plate as well as damage to the threaded holes in
the Grid frame.
22. Refit the control knob onto the shaft and gently push it
into place.
INSTALLING THE DIMMER IN A TWO-WAY SITUATION
1. A two-way installation is when a dimmer is used in
conjunction with a two-way switch, to control one light
from more than one position.
2. If replacing an old switch or dimmer, take carefully note
the terminals to which each wire is connected. (com.,
L1, L2 etc.) This will help to ensure correct connection
to the new dimmer.
3. Follow the instruction for installing a one-way switch
above, except using the circuit shown in Fig. 2 for the
terminal positions.
Please retain these instructions, or if you are not the end
user, please leave them with the product for future
reference.
Due to the many innovative protection features
incorporated in these dimmer modules, there are a number
of instances when the operation of certain safety features
could be interpreted by the user as the Dimmer having
malfunctioned. Before returning any Dimmer that is
considered faulty, please ensure none of the protection
features have operated. Refer to the “Product Features”
section of this leaflet.
CLEANING THE PRODUCT
In order to protect the quality surface finish of the Grid
front plate and the Dimmer module, periodic cleaning
should only consist of polishing with a dry lint free soft
cloth. On no account should abrasive or domestic cleaners
be used.
Figure 1 - One Way Switching
Figure 2 - Two Way Switching (only 1 dimmer can be used)
Figure 3 - typical mounting arrangement
Figure 4 – Module removal procedure
234689121824
400 480 480 480 480 480 480 720 720
320 380 380 380 380 380 380 580 580
400 480 480 740 740 940 940 1440 1800
320 380 380 600 600 750 750 1155 1440
Front plate size, Number of gangs
Max. Power/Load per row – Tungstan GLS lamps - W
Max. Power/Load per row – Mains Tungsen Halogen lamps
or Low Voltage Transformers – W or VA
Max. Power/Load for Total Plate – Tungsten GLS lamps - W
Max. Power/Load for Total Plate – Mains Tungsten Halogen
Lamps or Low Voltage transformers – W or VA
LOAD
L1
L
N
L2
C
DIMMER
SUPPLY
240V ~ 50Hz
LOAD
2 WAY SWITCH
L1
L
N
L2
C
DIMMER
SUPPLY
240V ~ 50Hz
L1
L2
C
®
MK Electric
Novar ED&S Ltd
The Arnold Centre, Paycocke Road, Basildon,
Essex SS14 3EA. U.K.
Tel: +44 (0) 1268 563000
Fax: 01268 563405
(UK Sales)
Fax: +44 (0) 1268 563360
(International)
email: technical@novar.com
web site: www.mkelectric.co.uk
Technical queries should be made to:
MK Electric, Technical Sales and Services Department
The Arnold Centre, Paycocke Road, Basildon, Essex SS14 3EA
Tel: +44 (0)1268 563720 Fax: +44 (0)1268 563064
All marks in this document identified with a R or TM symbol
adjacent to the mark are Trade Marks of Novar ED&S Limited.
48366PL Ed1 21/11/05 1:45 pm Page 4
/
