SECTION 2 - LAMPS AND LUMINAIRES
The two key components in a lighting system are the lamps and luminaries.
Lamps
There are two main types of lamps - incandescent filament lamps and gas discharge lamps.
Incandescent filament lamps work by heating a metal filament until it glows. The light produced is broad spectrum. These are commonly used in domestic situations and some may contain a halogen gas. They are low efficiency and short life but can be plugged directly into a power supply.
Gas discharge lamps are either based on ultraviolet light from gas discharge reatcing with a phosphor coating on the glass to give visible light (such as tubular fluorescent lights and low energy bulds) or a metal halide bulb (low and high pressure sodium) which produce visible light directly. These need additional equipment to work and cannot be plugged directly inot the mains supply. They have high efficiency and a long life.
Luminaires These are the fittings into which the lamps are placed to protect against weather and physical damage. They may also incorporate optical devices to control and direct the light to reduce uncontrolled light escape. They are generally either fixed like a lamp post) or variable angle (like a security light).
Table A2.2 below illustrates some common lamps types and Table A2.3 some common luminaire types.
Figure A2.2
Figure A2.3
Figure A2.3 Cont.
