Types of Lamps and illumination equipment

Lamps and illumination equipment

The illumination devices are subject to constant change due to developments in energy efficiency and electronics. For the choice of associated switching (e.g. contactors) and protective equipment (e.g. miniature circuit breakers and circuit breakers) not only the type of lighting equipment itself should be taken into account but also the kind of control circuit.

Particular attention should be paid to inrush currents caused by compensation capacitors and charging of electronic control devices.

This loading may be reduced by the attenuating effect of long lines.The startup and operational current loads should be obtained from the respective manufacturers. The below descriptions relate to the basic characteristics.

In general it is recommended to utilize a max. of 90 % of the current capacity of the switchgear as the current consumption of lighting equipment typically increases when the voltage increases.

Incandescent lamps

The filaments of incandescent lamps have a very low ohmic resistance when cold. This creates a high current peak when they are switched on (up to 15 · le). The making capacity of the switch gear must thus at least correspond to this value.

Upon switching off, only the rated current has to be disconnected due to the high resistance of the hot filaments.

Halogen lamps

Halogen lamps are actually a version of incandescent lamps and their behavior is basically the same as the latter. The lamps are often designed for low voltages and powered via a transformer or electronic mains adapter. Their inrush currents should be taken into account for switching on.

 

Discharge lamps


Discharge lamps such as fluorescent tubes, energy saving lamps, mercury vapor lamps, halogen metal vapor lamps or sodium vapor lamps require both a starting circuit and a current limitation device.

These devices may be conventional or electronic. Discharge lamps with electromagnetic series chokes have a low power factor and are therefore usually compensated.

The compensation capacitance leads to high inrush currents that must be taken into account when the switchgear is selected.

Most electronic series devices have a high power factor (e.g. cosĪ† ≈ 0.95), nevertheless during switching on there occurs a charging current surge that loads the switchgear accordingly.

When selecting the switchgear for high in-rush currents, the permitted rated power for the switching of capacitors should be taken into account as per utilization category AC-6b.

In order to prevent undesired release of miniature circuit breakers with the simultaneous activation of a number of fluorescent tubes, information is provided by the tube manufacturers on the maximum number of luminescent tubes (including series devices) that can be operated via a single
protective switch.

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