Current limiting devices for fluorescent lamps
A fluorescent lamp cannot be connected directly to the mains voltage, but has to be equipped with some device to limit the electric current.
The magnetic reactor ballast limits the current to the light source. The magnetic reactor ballast is arranged in classes due to its energy efficiency, accounting for self-losses and heat increase. The starting voltage is created by means of a starter.
Compensation for the reactive effect can be made by means of a capicitor.
HF-ballast is an electronic current limiting device. HF-ballasts provide a flicker free light, start the fluorescent lamp without flickering and increase the lamp life. Requires no fluorescent starter or capacitor.
HF-ballast units with continuously adjustable lighting control are available, such as; analogue sensors 1-10V, digital control, controlled by 230V impulse switches.
Leave the light on for 100 hours in full effect prior to using the lighting control.
Fluorescent lamps as a light source
There is a range of fluorescent lamps with different shapes, dimensions, effects and characteristics and they all have the benefits of high luminous efficiency and long lives.
The fluorescent lamp T8 has a diameter of 26 mm. Maximum luminous flux at approx. 25°C (ambient temperature at the tube). T8 is available with magnetic or electronic ballast.
Most frequent types:
Length (mm) Effect (W) and max luminous flux (Lumen)
590 18 W, 1350 lm
895 30 W, 2450 lm
1200 36 W, 3350 lm
1500 58 W, 5200 lm
The fluorescent lamp T5 has a diameter of 16 mm. Maximum luminous flux at approx. 35°C (ambient temperature at the tube). T5 is available with electronic ballast only. Two types available ; for max luminous efficiency (HE)and max luminous flux (HO):
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Length (mm)
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Type HE for max luminous efficiency Effect (W) and max luminous flux (Lumen)
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Type HO for max luminous flux Effect (W) and max luminous flux (Lumen)
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549
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14 W, 1350 lm
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24 W, 2000 lm
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849
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21 W, 2100 lm
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39 W, 3500 lm
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1149
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28 W, 2900 lm
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54 W, 5000 lm
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1449
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35 W, 3650 lm
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49 W, 4900 lm and
80 W, 7000 lm
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The colour temperature of the light source is measured in Kelvin. Colour temperatures of 3300-5300K are regarded to be neutral, below 3300K to be warm and in excess of 5300K to be cool.
The colour rendering of the light source is a measure of the ability correctly to reproduce colours. To indicate the ability of colour reproduction a colour rendering index, RA, is used on a scale of 0-100. A light source with a Ra value of 100 displays all colours exactly as they appear.