Fluorescent lamp without starter. Connection of fluorescent lamps without choke and starter. The principle of operation of the epra

Hello dear readers! I offer you the history of the creation of watches on gas-discharge indicators IN-14. A simple project at the beginning turned into a whole artistic composition that made me sweat a lot.

The watch has an accuracy correction and a backup in case of power failure.

background

It all started when Alexey (teXnik) posted your article. In close contact with the author of the article, I was able to repeat the project. The clock has been wired on a single double-sided board with a very ergonomic layout. Everything suited, but there was one drawback - the impossibility of correcting the accuracy of the course.

I began to pick up quartz resonators, but for some reason I could not achieve care for less than a minute in one day.

I decided, according to the old Soviet schemes, to assemble a stable generator based on logic elements.

The generator made it possible to achieve an accuracy of up to half a second in one day. The result is average, moreover, requiring the use of a frequency meter of a high accuracy class for tuning. In the tuned oscillator, it was necessary to lock the variable capacitance by varnishing it, which again led to a frequency shift for the simple reason that the varnish tightened the gaps of the tuning capacitor. In addition, the introduction of a stable oscillator circuit increased the current consumption of the clock.

After suffering for a week, I decided to try to repeat another watch project on lamp indicators, and, of course, with software correction of the course. The topic is not new and there have been many successful implementations of such an idea over the years.

Scheme of the new clock on PIC16F628A

The basis of the circuit is built on the PIC16F628A microcontroller, which sends signals to the K155ID1 decoder and controls the anode switches.

The circuit is powered by a single +12 V source. The LM78L05 type stabilizer provides +5 V to power the microcircuits. The high voltage required to power the gas discharge indicators was received from an inverter on the MC3403 chip. The output voltage is adjusted by a divider included in the feedback.
The disadvantage of such an inverter circuit is the absence of a buffer key in the field-effect transistor circuit. The total current consumption of the inverter circuit is 230 mA.
An indisputable plus is the adjustment of the output voltage, and as a result, the adjustment of the brightness of the indicators.

The firmware implements my main need - constant adjustment that affects the course of the clock without the use of precision quartz resonators. The alarm function was a nice bonus.

Practical implementation

Having appreciated all the advantages of this scheme, I decided to repeat it.
The assembled device was supposed to represent two boards with transitional contacts: a control board, on which 90% of all elements are located, and an indication board with IN-14 gas-discharge indicators installed on it.

The disadvantage of such an implementation is in dimensions, but on the other hand, there is also universality. You can separate the indication board for any other gas discharge indicators without touching the control board.

Starting and setting the clock

I collected all the elements, etched the boards and carried out the installation. It's time to check and configure the power supply. First, I started the PSU at idle. The 78L05 stabilizer worked as expected.
The inverter set to a voltage close to the lower limit of the indicators ignition - about 170-175 V using a 2kΩ trimmer.

I put the chips in the sockets and then the unexpected happened. For an unknown reason, the 78L05 chip broke through, the microcircuits burned out from a power surge.
As a result of the tests, I found out that I came across defective K155ID1 decoders. Checking the resistance between the power pins shows a value of about 10 ohms. This could cause the failure of the 78L05 stabilizer.

I installed a new serviceable decoder, went to the radio store for a new PIC16F628A chip, programmed it with .

This time, the start-up under load went without incident. The indicator lamps lit up.

The watch has 3 control buttons: correction, alarm and increment.
I will quote the words of the author of the firmware:

Implemented 2 display modes: hours-minutes and minutes-seconds. Switching with the "Increment" button.
- When you press the "Correction" button, the watch switches to the seconds correction mode (seconds are reset by the "Increment" button). The next press of the “Correction” button puts the clock into the minutes correction mode (minutes are increased by the “Increment” button). One more press of the "Correction" button - transition to the clock correction (the clock is increased by the "Increment" button). The next press of the “Correction” button returns to the hours-minutes display mode.
- When you press the Alarm button, the watch enters the alarm setting display mode. In this mode, use the "Increment" button to turn on the alarm. Switching on is confirmed by a short beep and a flashing dot turns on. The alarm setting is corrected after pressing the "Correction" button. After the first press - minutes, after the second - hours (increase with the "Increment" button). After the third press - the transition to normal mode.
- The watch has a correction function by adjusting the constant (the adjustment mode is activated when the "Correction" button is held for more than 1 second). The default constant is 1032 microseconds per second. When the clock lags, we increase the constant (the “Increment” button) by the amount of lag calculated in microseconds per 1 second. If the clock is in a hurry, we decrease the constant (the “Alarm Clock” button) according to the same principle.
- Return to the normal mode is carried out from the correction modes 3 minutes after the last pressing of any of the buttons.
- When the alarm goes off, an audible signal sounds, which is turned off by pressing any of the buttons or automatically after about 4 minutes.

For clarity, I offer you a short video. The video shows the time correction modes: reset seconds, set minutes, set hours.

I hold the button for more than 1 second and enter the constant adjustment mode. As you can see, my current constant is 1292 microseconds. Quite far from the initial value of 1032 microseconds.
It took me four days to correct the clock. Initially, the clock was behind by 2 minutes per day. It took 2 days to make rough adjustments and 2 days to fine-tune. Ultimately, I did not notice a lag or rush of the clock for a second during the week. Stroke correction completed.

After about 3 weeks, the battery 2032 was discharged and the watch stopped remembering the settings and the current time when the power went out. I note that the set constant does not get lost. I decided to get out of the situation simply - I introduced a more bulky battery - two AA batteries.

Unusual design case

Electronics is ready! Ahead - the highlight of the program - the body.

I worked very hard on the hull. From the very beginning, I did not want to make a typical Nixieclock watch with 4 lamps sticking out of the case. I wanted something more. To place decorative elements near the lamps, I chose the Gainta G0477 case with dimensions of 187 × 118x37 mm.

What have I not tried! Even mirrors and glass spheres, but I didn't like anything in the end. For a while, I abandoned the project and started working on the Pokémon amplifier, while thinking about all kinds of options for decorating the case of a tube watch. One day, on the way to work, my eyes rested on a destroyed column on one of the advertising posters. Imagination presented the idea of ​​ancient Greek columns and baths.
And then it dawned on me - there should be columns near the lamps on the clock! Still not fully presenting the implementation methods, I began to develop this idea. Two columns come out a bit dry, it is better to take something similar, such as Chinese or Japanese gates that stand at the entrances to temples.

When I returned home, I immediately sketched a sketch in Photoshop.

I really liked this option, but it was still a bit dry and there was a lot of free space on the case. I started thinking in the direction of Asian styles. What would you like to add?

I must tell you that even before the all-consuming passion for radio electronics, I was engaged in translations of Japanese fantasy manga (similar to comics). Therefore, dragons naturally came to mind. Namely, the Japanese river dragon. After working a little in Photoshop, I added a sketch.

The final sketch just blew me away. Urgently, drink! But the practice remained vague. Started running options. The first thing that came to mind was the deep etching of aluminum blanks with ferric chloride using a technology similar to LUT, which I successfully applied in my past projects.

The option is suitable, but the scope of the upcoming work was much larger, and it is problematic to process metal to the smallest detail.

It remains to use foil textolite. Working with one-sided foil textolite is many times easier than with aluminum.
Optimized the image for the possibility of image etching by LUT. With some shortcomings, I etched the "fee".

The most difficult thing remains - to cut out images from a single piece of textolite. A terribly long and tedious process that cannot be fulfilled without a creative impulse and a great desire. Rough saw cuts of pieces of textolite were carried out with a manual jigsaw, after which with small tweezers he bit off all available contours near the pattern with sharp wire cutters, up to gaps of 1.5-2 mm from the edge, so as not to damage the pattern itself in any case.

The internal parts were drilled with drills of various diameters, followed by precise removal. Then finishing with needle files. In the bins I had two sets of needle files of various shapes and sizes. For a long time and stubbornly he deduced each bend of the pattern, selecting and combining the desired size and shape of the needle files.

It took me about 2 weeks of concentrated work in my spare time to make the Dragon from a piece of textolite. He managed to torment his wife's musical ear with his "shirking".

After finishing the work, the fingertips on my right hand became rough, as if I had been playing the guitar in rehearsals for two hours a day for a week.

The dragon is finally cut. The next step is painting. Having fantasized one evening, I decided that I would paint it red. This is where the final name of the watch "Red Dragon" came from.

Went experimenting with paint. I immediately bought two cans of aerosol paint in the colors "Chinese Cherry" (acrylic) and "Raspberry" (alkyd). The names are not responsible for the accuracy of the shades and are conditional. None of the presented options satisfied me in the end. "Chinese cherry" turned out to be too dark, and alkyd "Raspberry" dried for a very long time, which is fraught with dust sticking during home painting. Just 3-4 large dust particles on a glossy mirror can kill all job satisfaction.

I ended up shopping in search of red matte paint. To my surprise, it turned out that such a paint does not exist in nature. That is, you can’t buy it in spray cans, for this you need to buy separately the main color paint, a matting additive and go to a specialized center to prepare the mixture. For my purposes, this is way too expensive.

The decision came unexpectedly. I saw metallic colors on the shelves. These paints are a transitional link between a glossy and matte surface, that is, they do not have a glossy mirror, and in the case of an acrylic base, they dry very quickly. Color chose under the name "Kalina".

Raspberries, viburnum, cherries - compote can be cooked.

I tested the paint on a sampler. Grabbed after 5 minutes, and not a single speck of dust had time to stick. Great, you can paint.

To paint such cases, I use a tricky “paint box” - I cut a 5-liter plastic bottle lengthwise into two halves, paint the part and cover it with one half. This method does not allow dust to settle on the surface, and the hole from the neck allows air to circulate.

Almost everything is ready. It remains to paint the inner contours of the dragon and the gate. The case is complex and requires skill. I took a thin brush and began to fill my hand on special stencils. My stencils are 3 words etched in aluminum. I circle them, look at the result, erase the paint with a solvent and start all over again, until the hand is stuffed to even strokes without departures beyond the boundaries of the engraving.
I sat for about an hour and realized that with rough pads on my fingers, I do not feel the pressure of the brush.

The solution turned out to be simple, but not obvious at first glance - a permanent marker for boards like Edding404.

With it, you can make even strokes with a thickness of 0.5 mm. I tried it on a stencil and realized that it turns out almost perfectly. There are no flights outside the borders, the only difficulty is in choosing the length of the stroke, in which the tip of the marker is not drained to the end. Yes, yes, this marker draws perfectly on smooth textolite, but quickly stops writing when touching matte (well absorbent) surfaces. The reason is that the supply of paint in a thin tip quickly dries up. In this case, you just need to wait 5-10 minutes before the tip is saturated with paint again.

I trained and started painting the dragon and the gate. Less than half an hour later, the marker stopped writing completely. No attempts to paint it worked. The marker is out of paint.

A distinctive principle of the connection scheme for fluorescent lamps is the need to include starting-type devices in it, the duration of operation depends on them.

In order to understand the circuits, it is necessary to understand the principle of operation of these fixtures.

A luminescent type lamp device is a sealed vessel filled with a special gas mixture. The calculation of the mixture was carried out in order to waste less gas ionization energy in comparison with conventional lamps, due to this, you can save a lot on lighting a house or apartment.

For constant illumination, it is necessary to hold the glow discharge. This process is ensured by supplying the desired voltage. The problem lies only in the following situation - such a discharge appears from the supply voltage, which is higher than the working one. But this problem was also solved by the manufacturers.

On both sides of the lamp, electrodes are installed that receive voltage and maintain the discharge. Each electrode has two contacts with which the current source is connected. Due to this, the zone that surrounds the electrodes is heated.

The lamp lights up after heating each electrode. This happens due to the impact on them of high-voltage pulses and the subsequent work of the voltage.

When exposed to a discharge, the gases in the lamp container activate the emission of ultraviolet light, which is not perceived by the human eye. In order for human vision to distinguish this glow, the bulb inside is covered with a phosphor substance, which shifts the frequency interval of illumination to the visible interval.

By changing the structure of this substance, a change in the range of color temperatures occurs.

Important! You can not simply turn on the lamp in the network. The arc will appear after the heating of the electrodes and the pulsed voltage are ensured.

Special ballasts help to provide such conditions.

The nuances of the connection scheme

A circuit of this type must include the presence of a throttle and a starter.

The starter looks like a small source of neon lighting. To power it, you need an AC power supply, and it is also equipped with a certain number of bimetallic contacts.

The choke, starter contacts and electrode threads are connected in series.

Another option is possible when replacing the starter with a button from the input call.

The voltage will be carried out by holding the button in the pressed state. When the lamp is lit, it must be released.

• the connected choke stores electromagnetic energy;
• with the help of starter contacts, electricity is supplied;
• current transfer is carried out with the help of tungsten filaments heating electrodes;
• heating of electrodes and starter;
• then the starter contacts open;
• the energy that is accumulated with the help of the throttle is released;
• the lamp turns on.

In order to increase the efficiency, to reduce noise, two capacitors are introduced into the circuit model.

The advantages of this scheme:

Simplicity;

Democratic price;

She is reliable;

The disadvantages of the scheme:

Large mass of the device;

Noisy work;

The lamp flickers, which is not good for vision;

Consumes a large amount of electricity;

The device turns on for about three seconds;

Poor performance at sub-zero temperatures.

Connection order

Connection using the above scheme occurs with starters. The option considered below has a 4-65W S10 starter model, a 40W lamp and the same power at the throttle.

Stage 1. Connecting the starter to the pin contacts of the lamp, which look like incandescent filaments.

Stage 2. The remaining contacts are connected to the throttle.

Stage 3. The capacitor is connected to the power contacts in parallel. The capacitor compensates for the reactive power level and reduces the amount of interference.

Features of the connection scheme

Due to the electronic ballast, the lamp provides a long period of operation and saves energy costs. When operating with voltages up to 133 kHz, the light spreads without flicker.

Microcircuits provide power to lamps, heating of electrodes, thereby increasing their productivity and increasing their service life. It is possible, together with the lamps of this connection scheme, to use dimmers - these are devices that smoothly adjust the brightness of the glow.

The electronic ballast converts the voltage. The action of direct current is transformed into a high-frequency and alternating current, which passes to the electrode heaters.

The frequency increases due to this there is a decrease in the intensity of heating of the electrodes. The use of electronic ballast in the connection scheme allows you to adjust to the properties of the lamp.

Advantages of this type of scheme:

• big savings;
• the light bulb turns on smoothly;
• no flicker;
• the lamp electrodes are carefully heated;
• permissible operation at low temperatures;
• compactness and small weight;
• long term validity.

Cons of this type of scheme:

• the complexity of the connection scheme;
• high installation requirements.

How to connect lamps

The lamp is connected in three stages:

The electrodes are heated, due to which the device starts up neatly and measuredly;

A powerful impulse is created, which is required for ignition;

The operating voltage is balanced and applied to the lamp.

Connection order

Stage 1. Parallel connection of a starter to each lamp.

Stage 2. Serial connection using a choke of free contacts to the network.

Stage 3. Parallel connection of capacitors to the lamp contacts. Due to this, interference is reduced, as well as reactive power compensation.

Video - Connecting fluorescent lamps

Fluorescent lamps are commonly used to illuminate supermarkets, classrooms, industrial facilities, public indoor spaces and more. With the advent of more modern types, which are available with a standard E27 base, they began to be used at home.

Over time, they are gaining more and more popularity. But the circuit for switching on fluorescent lamps is quite complicated and requires special knowledge in this area. Usually they are connected in two circuits, which we will talk about later. But first you need to understand the principle of operation and the structure of such a lamp.

Let's take a look at what a fluorescent lamp is and how it works. It is a glass tube that starts working due to a discharge that ignites the gases inside its shell. A cathode and an anode are installed at both ends, it is between them that a discharge occurs, which causes a starting fire.

Vapors of mercury, which are placed in a glass case, when discharged, begin to emit a special invisible light, which activates the work of the phosphor and other additional elements. It is they who begin to radiate the light that we need.

The principle of the lamp

Due to the different properties of the phosphor, such a lamp emits a wide range of different colors.

We connect using electromagnetic ballast

Electromagnetic ballast apparatus, the abbreviation for it is EmPRA. Also often referred to as a choke. The power of such a device should be equal to the power that the lamps consume during operation. A rather old circuit, with which fluorescent lamps were previously connected.

Circuit with electromagnetic ballast

The principle of operation of such a device is as follows. After the start of the current supply, it enters the starter, after which the bimetallic electrodes close for a short period of time. Due to this, all the current that appears in the circuit is closed between the electrodes and is limited only by the resistance of the inductor.

Thus, it increases by about three to four times, and the electrodes begin to warm up almost instantly.

Thus, it is the choke that forms a strong discharge in the environment of gases, and they begin to emit their light. After switching on, the voltage in the circuit will be approximately half of the input from the network.

This indicator is not enough to create a second pulse, which is why the lamp starts to work stably.

What disadvantages does it have?

1. Comparing with the scheme where it is used, the power consumption is ten to fifteen percent higher.
2. Depending on how much the lamp has already worked, the start-up period will increase and can reach up to three to four seconds.
3. Such a scheme for connecting fluorescent lamps over time contributes to the appearance of buzz. This sound will come from the throttle plates.
4. During the operation of the lamp, there will be a fairly high coefficient of light pulsation. Such a phenomenon negatively affects a person’s vision, and with a long stay, the action of such flickering rays can cause visual impairment.
5. Unable to work at low temperatures. Thus, there is no possibility to use such lamps on the street or in unheated rooms.

We connect the lamp using an electronic ballast

The main difference between such a system and an electromagnetic one is that the voltage that reaches the lamp itself has an increased frequency starting from 25 and reaching 140 kHz. By increasing the frequency of the current, the flicker index is significantly reduced, and it is at a level that is no longer too harmful to the human eye.

Connection with electronic ballast

The electronic ballast system uses a special self-oscillator in its circuit, such an addition includes a transformer and an output stage on all transistors. Often, manufacturers indicate the circuit directly on the back of the luminaire unit. Thus, you immediately have a good example of how to properly connect and install the device to work from the network.

Advantages of the starter wiring diagram

• The starter system extends the life of the luminaire.
• The special operating principle also extends the service life by about ten percent.
• Thanks to the principle of operation, the device saves about twenty to thirty percent of the electricity consumed.
• Facilitated installation, as the manufacturer indicates the scheme according to which the installation of the lamp you have taken should take place.
• During operation, flickering and noise from the lamp are almost completely absent. Such phenomena are present, but they are invisible to humans and do not affect health in any way.

There are models that support the installation of a dimmer as a regulator. The installation of such devices is somewhat different from the standard installation.

Summarize

We tried to solve the question of how to connect a fluorescent lamp, showed the diagrams by which fluorescent lamps are connected. Having dealt with the scheme of electromagnetic and electronic ballast, you can decide which one is better to use in your case. But since the first one has a number of significant drawbacks, then most likely the choice will fall on the electronic ballast.

Causes of malfunctions - problem solving

The electronic throttle circuit was invented later, and was developed specifically in order to remove all the shortcomings of the electromagnetic counterpart, in order to maximize the quality of lighting using fluorescent lamps.

Installing such devices is no longer difficult, as it used to be. Manufacturers have begun to indicate the installation scheme on the back of the device, which greatly facilitates the work of the installer.

Despite the emergence of more "advanced" LED lamps, daylight fixtures continue to be in demand due to their affordable price. But there is one catch: you can’t just plug them in and light them up, unless you put a couple of additional elements. The electrical circuit for connecting fluorescent lamps, which includes these parts, is quite simple and serves to start this type of luminaire. You can easily assemble it yourself after reading our material.

The device and features of the lamp

The question arises why, to turn on such light bulbs, you need to assemble some kind of circuit. To answer it, it is worth analyzing their principle of operation. So, fluorescent (otherwise - gas-discharge) lamps consist of the following elements:

1. A glass flask whose walls are coated on the inside with a substance based on phosphorus. This layer emits a uniform white glow when hit by ultraviolet radiation and is called a phosphor.
2. On the sides of the flask there are sealed end caps with two electrodes each. Inside, the contacts are connected by a tungsten filament coated with a special protective paste.
3. The daylight source is filled with an inert gas mixed with mercury vapor.

Reference. Glass flasks are straight and curved in the shape of the Latin "U". The bend is made in order to group the plug-in contacts on one side and thus achieve greater compactness (example - widely used light bulbs - housekeepers).

The glow of the phosphor causes a flow of electrons passing through mercury vapor in an argon environment. But first, a steady glow discharge must occur between the two filaments. This requires a short high voltage pulse (up to 600 V). To create it when the lamp is turned on, the above-mentioned details are needed, connected according to a certain scheme. The technical name of the device is ballast or control gear (ballast).

In housekeepers, the ballast is already built into the base

Traditional scheme with electromagnetic ballast

In this case, the key role is played by a coil with a core - a choke, which, thanks to the phenomenon of self-induction, is able to provide a pulse of the required magnitude to create a glow discharge in a fluorescent lamp. How to connect it to power through a choke is shown in the diagram:

The second element of the ballast is a starter, which is a cylindrical box with a capacitor and a small neon bulb inside. The latter is equipped with a bimetallic plate and acts as a circuit breaker. Connection through an electromagnetic ballast works according to the following algorithm:

1. After the contacts of the main switch are closed, the current passes through the inductor, the first filament of the lamp and the starter, and returns through the second tungsten filament.
2. The bimetal plate in the starter heats up and closes the circuit directly. The current increases, which causes the tungsten filaments to heat up.
3. After cooling, the plate returns to its original shape and opens the contacts again. At this moment, a high voltage pulse is formed in the inductor, causing a discharge in the lamp. Further, to maintain the glow, 220 V from the mains is enough.

This is what the starter filling looks like - only 2 parts

Reference. The principle of connection with a choke and a capacitor is similar to a car ignition system, where a powerful spark on candles jumps at the moment the high-voltage coil circuit breaks.

The capacitor, installed in the starter and connected in parallel to the bimetallic breaker, performs 2 functions: it prolongs the action of the high-voltage pulse and serves as protection against radio interference. If you need to connect 2 fluorescent lamps, then one coil will be enough, but two starters will be required, as shown in the diagram.

More information about the operation of gas discharge bulbs with ballasts is described in the video:

Electronic switching system

The electromagnetic ballast is gradually being replaced by a new electronic ballast system, devoid of such disadvantages:

• long lamp start (up to 3 seconds);
• crackling or clicking sound when turned on;
• unstable operation at air temperatures below +10 °С;
• low-frequency flicker that adversely affects human vision (the so-called strobe effect).

Reference. The installation of daylight sources is prohibited on production equipment with rotating parts precisely because of the strobe effect. With such lighting, an optical illusion occurs: it seems to the worker that the machine spindle is stationary, but in fact it is spinning. Hence the accidents at work.

Electronic ballast is a single unit with contacts for connecting wires. Inside there is an electronic board of the frequency converter with a transformer, replacing the outdated ballast of electromagnetic type. Connection diagrams for fluorescent lamps with electronic ballast are usually depicted on the unit body. Everything is simple here: the terminals are marked where to connect the phase, zero and ground, as well as the wires from the lamp.

Starting bulbs without a starter

This part of the electromagnetic ballast breaks down quite often, and there is not always a new one in stock. In order to continue to use the daylight source, you can put a manual breaker instead of a starter - a button, as shown in the diagram:

The bottom line is to manually simulate the operation of a bimetallic plate: first close the circuit, wait 3 seconds until the lamp filaments warm up, and then open. Here it is important to choose the right button for a voltage of 220 V so that you do not get electrocuted (suitable for a regular doorbell).

During the operation of a fluorescent lamp, the coating of tungsten filaments gradually crumbles, which can cause them to burn out. The phenomenon is characterized by blackening of the edge zones near the electrodes and indicates that the lamp will soon fail. But even with burnt out spirals, the product remains operational, only it must be connected to the mains according to the following scheme:

If desired, a gas-discharge light source can be ignited without chokes and capacitors, using a ready-made mini-board from a burned-out energy-saving light bulb that works on the same principle. How to do this is shown in the following video.