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Lightbulb Types and Other Useful Information

Energy Saving Options

There are an increasing number of alternative "energy saving" lamps available. Depending on the type of lamp, the energy saving potential and type of light emitted is different - this guide provides a summary of some popular types.

Dedicated Low Energy

The fittings themselves contain control gear which is designed to operate "pin based" fluorescent lamps. These lamps have unique lampholder types which are only suitable for the type of lamp detailed in the specification. They come in several different shapes dependant on the lamp holder.

They consume around 20% of the energy used by a conventional incandescent (GLS) lamp and have a life of between 10 and 15 times longer (dependant on specific lamps).

Retro Fit Low Energy (Self ballasted lamps):

This type of lamp is available to suit many of the common lampholder types, (BC, ES, SES, GU10) and is suitable for use in many of the fittings. It is a fluorescent lamp, similar in operation and energy saving to the dedicated low energy lamps but with the control gear housed within the lamp itself. This allows them to be fitted in fittings designed for use with conventional GLS lamps. They are available in a variety of shapes and sizes of varying wattages. A guide for comparable wattages can be found below.

Incandescent Lamp Retro Fit Lamp (Self Ballasted)
25 Watt 57 - 7 Watt
40 Watt 8 - 10 Watt
60 Watt 11 - 14 Watt
75 Watt 15 - 17 Watt
100 Watt 18 - 22 Watt
150 Watt 23 - 27 Watt

The type of light will vary dependant on the "colour temperature" of the lamp - a lamp marked 827 (or 2700k) will produce a warm light, similar in appearance to a conventional GLS whilst an 835 (3500k) will produce a colder light which may be more suitable for some contemporary fittings. Lamps with a colour temperature above 5000k are referred to as "daylight" and give excellent colour rendering suitable for task lighting.

NOTE: This type of lamp is not suitable for use on products which have touch dimmers or which are intended to be dimmed.

Bulb Types

Incandescent and Energy Saving

NOTE: Energy saving bulbs are available in the standard cap sizes to fit most light fittings (BC/B22, SBC/B15, ES/E27, SES/E14 and in GLS, candle and stick shapes), but the overall dimensions can differslightly due to the width and heigh of the tubes. It is advised to test for fit before purchase.

BC/B22 GLS Bayonet cap general light service BC/B22 GB Bayonet cap golf ball BC/B22 CNDL Bayonet cap handle
SBC/B15 GB Small baynot cap golf ball SBC/B15 CNDL Small bayonet cap handle bayonet cap handle
ES/E27 GLS Edison screw general light service ES/E27 GB Edison screw golf ball ES/E27 CNDL Edison screw handle
SES/E14 GB Small Edison screw golf ball

12v Halogen

MR16 12 VOLT Dichroic reflector (heat backwards), Aluminium reflector (heat forwards)
  • Available in 20, 35, 50W
  • Beam angles 10?? - 60??
  • Available in 10, 20, 35, 50W

Mains Halogen


Aluminium reflector (light & heat forward)

GZ10 Dichroic reflector (light forward, heat backwards)
  • Available in 35 - 50W
  • Beam angles 25?? - 38??
  • Available 25, 40, 60, 75W
Linear Halogen
  • 78mm - 60, 100W
  • 118m - 150, 200, 300W

NOTE: Always observe the maximum wattage rating on the fitting.

Low Voltage Products

Electronic Transformers

A dimmer switch suitable for trailing edge (also described as phase lagging) is most likely to be compatible. This information is included in instructions for the appropriate products.

Toroidal Transformers

A dimmer switch suitable for inductive loads must be selected.

Dimmer Switches

A dimmer switch is a third party accessory and compatibility with our products is not guaranteed. These notes are for guidance only. For further advice, please contact a qualified electrician or the manufacturer of the dimmer switch you intend to use.

DO NOT USE dimmer switches on products which contain fluorescent lamps (including fluorescent "energy saving" lamps).

Please note that buzzing from the transformer is frequently caused by the dimmer switch - this may be because the wrong type of dimmer switch has been selected but it is quite normal for there to be some buzzing from either the dimmer switch or the transformer of any item being dimmed. A slight buzz is not indicative of a problem with the fitting or dimmer, it is a normal by-product of dimming the item. A more serious buzzing is almost always a result of using an incompatible/incorrect dimmer.

Low Energy Fluorescent

Compact Fluorescent Available with built-in ballast with ES or BC fitment for replacement of GLS bulbs. Ideal for lights that will be left on for long periods, i.e. outside, hall or porch lights. 2D
  • GR8 = 2 pin = 16W
  • GR10q = 4 pin = 23, 38W
Requires special fittings with built-in ballasts. Fixed wattage cannot be changed.
PL Lamps
  • G24d-1, G24d-2, G24d-3 (d = duo = 2 pin)
  • G24q-1, G24q-2 (q = quatro = 4 pin)
  • Available 10 - 26W
Requires special fittings with built-in ballasts. Fixed wattage cannot be changed.

Commonly Used Lighting Symbols and What They Mean

Class 1 240 volt The fitting requires a connection to earth. 'FX' marked Mounting surface of fitting can exceed 90??C. Not suitable for mounting on flammable surfaces. Minimum distance from illuminated surface 0.3m. Distance depends on wattage and reflector. Usually only used for products with reflectors built in or MR16, GU10. Ensure light source is not too close to surfaces causing them to overheat.
Class 2 240 volt 2 core double insulated - no earth connection required. Miniumum distance from illuminated surface - 0.3m Distance depends on wattage and reflector. Usually only used for products with reflectors built in or MR16, GU10. Ensure light source is not too close to surfaces causing them to overheat.
Class 3 12 volt Extra low voltage.
Replace broken protective glass (either round or rectangular). Some halogen and metal halide bulbs require a protective shield to offer protection should the bulb shatter. The shield must be replaced if broken to maintain security.
'F' marked Mounting of surface of fitting will not exceed 90??C. Suitable for mounting on flammable surfaces. Self shield lamp Warns that the use of glass fronted MR16, GU10 or low pressure capsule lamps must be used.

The Lightingworkshop - Mon Dec 18 06:52:17 GMT 2017 [web4]