Final Report Lot 9: Public street lighting - Amper

3.1.4 Influence of lamp and ballast operation under non-standard conditions
The performance parameters defined in chapter 1 are obtained under standard test conditions.
Photometric data is obtained under test conditions specified in standard CIE 121-1996 on 'The
Photometry and Goniophotometry of Luminaires'. An important parameter that can deviate in
real life is temperature (the default test temperature is 25 °C).
Electrical data (e.g. power, ..) are also obtained under test conditions specified in standard EN
60598-1: 2004 on 'Luminaires. General requirements and tests'. An important parameter that
can deviate in real life is line voltage, the default line voltage in EU 25 is 230 VAC with an
exception for the UK (240 VAC).
Hereafter we will discuss four factors that can influence energy consumption of luminaires in
real life, they are: temperature, line voltage, lamp voltage and the ageing of the power factor
compensating capacitor. None of these power consumption-influencing factors are taken into
account when dimensioning a lighting installation according to standard EN 13201-3.
It is important to realise that electronic ballasts are far less sensitive to these influences and
therefore a compensation factor will be introduced in this study.
1. Temperature:
Lamp efficacy and power consumption of fluorescent lamps are influenced by temperature.
Therefore fluorescent lamps are not often used for outdoor lighting.
2. Line voltage:
Power consumption and light output of gas discharge lamps vary with line voltage when
electromagnetic ballasts are used, typical +/- 20 % power variation with +/- 10 % variation
of line voltage. Line voltage variations of +/- 10 % are not exceptional in the public grid
and are standard allowed, moreover in street lighting voltage drop over long lines can occur.
Electronic ballasts with power control features can reduce these variations. By
consequence it could be justified to equip lamps with this power control feature at a lower
power set point (e.g. 90 %) because they still guarantee more minimum maintained light
than ferromagnetic control gear. At present there is no clear standard that already enables
this.
3. Lamp voltage:
Power consumption and light output of gas discharge lamps vary also with lamp voltage
when electromagnetic ballasts are used. Lamp voltage can vary with production variations
and generally increases with aging. By consequence power consumption over lamp life
(with electromagnetic ballasts) is not constant. Taking lamp and line voltage variations into
account together, lamp power can vary strongly (+/- 30 %) with ferromagnetic ballasts.
Only electronic ballast with power control features could overcome this problem.
4. Power factor compensating capacitor aging:
Power factor compensation capacitors are used with ferromagnetic control gear. The
capacitance decreases with capacitor age. Poor performance of this capacitor is causing an
increase of useless currents in the distribution grid and additional power losses in this
distribution grid. Moreover discharge lamps are causing third harmonic currents that cannot
be compensated in ferromagnetic control gear with capacitors. These third harmonic
currents (limited by EN 61000-3-2) can cause increased magnetic losses in distribution
transformers. Only electronic ballast with pure sine wave electronic power factor correctors
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