Fluorescent lamps have long been widely used both in everyday life and in other (very different) areas: lighting in production and in public institutions, operating rooms, illuminated outdoor and indoor advertising, etc.
"Pros" of fluorescent lighting
Compared to incandescent lamps, fluorescent lighting fixtures have a number of undeniable advantages:
- high luminous intensity with a wide range of light propagation;
- increased reliability of lighting devices;
- wide temperature range in which fluorescent lamps can operate without interruption;
- small intrinsic heating of the lamp body or other lighting device;
- Emission of light in a strictly defined spectrum and mode that is gentle on the eyes;
- outstanding performance and durability - up to 20,000 hours of operation.
Auxiliary elements
Work smoothlylighting fixtures are designed to provide parts such as starter motor and choke.
A starter for fluorescent lamps is necessary to ensure the "ignition" of electrical discharges in them. If the device is in the off state, the starter is not closed. The closing process occurs when electricity is supplied to the circuit. Then, when the lamp is lit, the voltage in it disappears, and the starter returns to its original (idle) state.
A choke is an inductive coil into which a metal core is inserted. Usually for lamps, it is selected with the same power as the lighting device itself. Otherwise, the lamps are threatened with overload and failure much earlier than expected.
The role of the choke is to limit the supply of current to the level required by a particular lighting fixture.
Throttle functions
Choke for fluorescent lamps performs several important functions. Firstly, it ensures the ignition of the filament, and secondly, the required current power is regulated. In a lighting device, it is a kind of ballast, taking on extra watts in the electrical circuit. According to the level of absorbed power, this element is divided into three groups:
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choke for fluorescent lamps choke for class D fluorescent lamps with medium absorption;
- class C - low level;
- class B - super low.
A high-quality choke for fluorescent lamps, the power of which is from 36 to 40 watts, takes on about 6 watts, i.e. 15% of total power. And the lower the power of the lamp, the more significant its difference with the throttling performance. Therefore, the luminous efficacy of a lighting device in real conditions is always somewhat less than the parameters indicated in the instructions for them.
Choke for fluorescent lamps creates the effect of a phase shift between voltage and current. Electrical networks create a voltage in the form of a sine. In conventional incandescent lamps, the shape is the same. But in luminescent ones, the "choke" current lags behind the main one (and the graph of the curves is already different).
As an alternative, in many designs of lighting fixtures and advertising stands, the starter and choke for fluorescent lamps are replaced by a special device that converts electrical frequencies at the level of automation. It "starts" the lamps at any external temperature, increases the stability of work and the intensity of light emission. Devices with such a device work much longer. Thus, electronic ballast can have several types and different performance. Naturally, this affects the cost of devices.
