Throttless inclusion of a fluorescent lamp. Encyclopedia of radio electronics and electrical engineering

Encyclopedia of radio electronics and electrical engineering / Lighting

 Comments on the article

We bring to your attention a circuit for replacing a low-frequency choke installed in luminaires with fluorescent lamps (LDS). The need for such a device is due to high energy losses in the inductor (as a result, its heating) and a high level of low-frequency noise during its operation. The device is based on the circuitry of converters for base-type LDS.

This is a pulse high-frequency self-generating converter. The input mains voltage is applied to the contacts XP1-XP2, rectified by VD9-VD12 and smoothed by C6. The R1C3 chain serves to reduce the penetration of RF interference into the primary network and limits the inrush current when turned on.

The lamp is connected to the contacts XP3-XP4 one filament and XP5-XP6 - the other. The VD1-VD4RTC1 circuit prevents overvoltage at the output of the converter at the moment the lamp is ignited, protecting the keys. The R7C7VD7VD8 chain serves for a stable start. Diodes VD5VD6 introduced to eliminate voltage spikes when switching transistors.

The converter is loaded on the lamp through the L1 RF choke, the dimensions of which are significantly reduced compared to the standard LF choke. Capacitor C2 provides the initial flow of current through the filaments of the lamp at the moment of switching on.

The power of all resistors is 0.125 W, with the exception of R1 - with a power of 1 W. RTC1 is a positive resistance thermistor, manufacturer unknown. Rated voltages of capacitors: C7 - 63V; C1,C4 - 250V; C3, C6 - 400V; C2, C5 - 630V. The author used non-polar capacitors from National Semiconductors and Philips. Capacitor C6 can be reduced to 20uF. Zener diodes VD2 and VD3 can be replaced with one unipolar one with a stabilization voltage of 47-60 Volts. Diode VD8 - trigger diode DB3 manufactured by SGS-THOMSON.

Inductance L2 - "droplet" in a molded case. Inductor L1 is wound in bulk with 300 turns of PEV-2-0.3 wire on a M2000NM ferrite core, size Sh4x4. The windings of the TR1 transformer are wound with PEV-2-0.3 wire on a M2000NM ferrite ring of size 10x6x4.5 and contain 7 turns (1-2), 3 turns (3-4), 3 turns (5-6), and the beginnings of the windings correspond to even numbers in numbering.

The printed circuit board was designed for installation in a standard luminaire housing with mounting holes at a distance of 140mm and a choke volume of 100x35x35.

In the board with dimensions 100x35 and thickness 2mm, grooves were made into which duralumin plates 15x40 were inserted and clamped, in which holes d = 4.2mm were made for attaching the device to the lamp body. The board is recessed into the body of the lamp so as to exclude electrical contact with the body. For the same purpose, the assembled board is coated with a protective varnish. Transistors VT1 and VT2 do not require installation on a radiator. The wires going to the lamp contacts must be twisted together. All connections must be made with wires capable of 1A current and resistant to the environment in which the luminaire is intended to be used.

Publication: radiokot.ru

See other articles Section Lighting.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Artificial leather for touch emulation 15.04.2024

In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>

Petgugu Global cat litter 15.04.2024

Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>

The attractiveness of caring men 14.04.2024

The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>

Random news from the Archive Tablet Chuwi HiPad Max 25.08.2022 The Chinese company Chuwi introduced the HiPad Max tablet, which supports two SIM-cards. The device is based on the SoC Snapdragon 680, that is, there is no 5G support here. The screen with a diagonal of 10,36 inches has a resolution of 2000x1200 pixels, and the frame thickness does not exceed 7 mm. Also, the tablet received 8 GB of RAM, 128 GB of flash memory, four speakers, it can offer Wi-Fi 5, a 7000 mAh battery and Widevine L1 support, which will allow you to watch videos from many streaming services in normal quality and resolution. Dimensions are 246,5 x 156,25 x 8 mm with a weight of 440 g. The tablet runs Android 12. The novelty costs $400, although the first few days after the start of sales it could be bought for only $200.

Other interesting news:

▪ Mercedes electric cars with wireless charging

▪ Computer in a baby's cradle

▪ Male characters in games speak twice as often as females

▪ Dangerous sequins

▪ Breathe and think

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ website section LEDs. Article selection

▪ article Banking. Lecture notes

▪ article Why do our milk teeth fall out? Detailed answer

▪ Article Island Madagascar. Nature miracle

▪ article Color and music installations, garlands. Directory

▪ article The amazing movement of coins. Focus Secret

Leave your comment on this article:

All languages ​​of this page

Arabic	Hebrew	Polish
Bengali	Hindi	Portuguese
Chinese	Italian	Spanish
English	Japanese	Turkish
French	Korean	Ukrainian
German	Malay	Vietnamese

Home page | Library | Articles | Website map | Site Reviews

www.diagram.com.ua
2000-2024