Discharge lamp installation

There is an increased use of electronic devices in electrical installation work for example, in dimmer switches and ignitor circuits of discharge lamps. These devices should be temporarily disconnected so that they are not damaged by the test voltage of, for example, the insulation resistance test (IET Regulation 612.3). 

The selection of the source of light appropriate to the circumstances depends on several factors. It is important to consider efficiency, ease of installation, costs of installation and running, maintenance, lamp life characteristics, size, robustness and heat and colom output. The efficiency of any lamp (often termed efficacy) can be expressed in terms of light output per unit of electricity used (lumens per watt). Generally speaking, incandescent lamps are less efficient than discharge sources. 

In any choice between incandescent and the other types of lamp the total lighting costs must take into account not only running costs but also installation and replacement costs. Incandescent lamps are much cheaper to buy and install, they give out light immediately they are switched on and they can be dimmed easily, but tiiey are more expensive to run and have short lives, thus increasing maintenance costs. High pressure discharge... 

As the object is to test the installation and not the connected apparatus, which should have been tested by the maker, it should be prepared by removing lamps and, for discharge lighting, unplugging or disconnecting one pole of capacitors or starting devices, also one pole of bell transformers. 

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