• 05.04.2019 12:21
• Parent Category: Projects
• Category: Automation
• Views: 645

Why do you need a transformer in a pulse converter? electrical energy? Part 1

Alexander Rusu, Odessa

There are a lot of pulse converter circuits for electrical energy. Step-down, step-up, inverting, forward, flyback, with the output of the middle point of the transformer (Push-Pull), half-bridge, bridge and even “skew-bridge” (two-transistor) - even an experienced specialist can easily get lost and “drown” in them, not to mention beginners Moreover, they all solve the same problem - converting voltage of one value into one or more voltages of another level. In addition, sometimes they also provide galvanic isolation - electrical isolation of input circuits from output circuits. But why so many schemes? Can't you come up with one? universal solution, which could be used in any situation?

Cyclic timers themselves can find application in the most different devices automation, be it periodic turning on of fans to ventilate the room, turning on indoor quartz lamps for air disinfection, etc. This entire continuous cycle with a certain ratio of work/pause time intervals can last for several days.

In this article I want to look at the operation of two such automation circuits for cyclic switching on an electric motor in a honey creaming installation.

In short, why is this necessary? Over time, honey is subject to crystallization, becomes hard, and so that the honey reaches the consumer in less time. solid state, was more plastic, it is subjected to a technological procedure called “creaming”. The honey is placed in a container, where the blades mechanically mix it at a certain speed and cyclicity, for example: the blades rotate for 15 minutes, mixing the honey, and then there is a 15-minute pause, and so on in an endless cycle. It is not easy to assemble such an automation circuit on a microcontroller. special labor, but not for radio amateurs who have not yet mastered microcontrollers. To make assembly easier for beginner radio amateurs, I offer 2 options without the use of programmers and without microcontrollers.

A selection of simple automatic amateur radio designs made by yourself. It presents various schemes automation such as touch switches, automatic control various devices and objects, various timers and automatic lights, lighting switches and automatic relays.

Amateur radio designs remote control on IR rays- The infrared control device consists of two blocks - a transmitter and a receiver with a possible range of up to seven meters. The circuit is built using a PIC12F629 microcontroller

Control household appliances via radio call. Nowadays there are a wide variety of low-power communication devices on sale that are available without registration, such as VHF pocket radios, radio-controlled toys, and recently radio bells have appeared. In general, the amateur radio design is very interesting in terms of its breadth of application. It consists of two blocks - a remote control button and the bell itself.

Remote control of four objects. The coding system allows you to control the alarm system by responding only to your remote key, or to several different devices in the same room

Amateur radio circuits for remote load control on the PIC12f629 microcontroller for four channels there are two versions of firmware for the RC-5 or NEC standard

Power switch with remote control via telephone network designed to work in the telephone network common use. It allows you to remotely turn on and off low- and medium-power network electrical appliances using a telephone line.

At 220 V, current flows through resistor R1 and the rectifier diode, charges the capacitor, and the relay operates. If the voltage is less than 180 V, the moving contact switches to the 127 V contact

When we apply a voltage of 220 V, current flows through resistor R1, rectifier diode VD1, charges capacitor C1, and the relay is activated. In this case, its contacts are in the position as shown in the diagram. If the voltage is less than 180 V, the current through the relay coil is not enough to operate it, and the moving contact switches to the 127 V contact. The switch is adjusted by selecting resistor R1. In this case, the relay contacts are disconnected from the transformer. Using an autotransformer, set the network voltage to about 180 V and select resistor R1 so that the relay turns off.

The basis of the amateur radio device is a relaxation generator based on a dinistor. This alarm device monitors not only the increase in the mains voltage, but also its decrease

To manufacture this device, you need a wirewound variable resistor of type SP5-30 or other suitable power with a resistance of about 1 kOhm.

When you press the button, a positive pulse is sent to the thyristor. It opens and the magnetic starter KM1 turns on, which turns on the load with its contacts. The next time you press the button, the voltage from the charged capacitor is supplied to the thyristor in reverse polarity, it closes and turns off the magnetic starter

A selection of amateur radio developments of humidity sensors that are designed to include forced ventilation premises for high humidity air, can be installed in the kitchen, bathroom, cellar, basement, garage

DIY sensor design that, when wet, begins to emit warning sounds. Moreover, it starts signaling only 10 seconds after getting wet; there are two types of signaling: sound and light

The device of a touch switch is considered, which can be easily and quickly assembled with your own hands. The touch switch can be used in various situations, for example, you can turn off the light of a lamp after a time interval specified by the circuitry

Very often in everyday life and households it is necessary to automatically turn on or off the load at a certain time, for this I propose to consider two designs assembled on the basis of the IRF7309 transistor assembly containing two field-effect switching transistors, one of which is with an n-type channel, and the other is a p-type .

These transistors have a small channel resistance of open state, low leakage current in the closed state and are capable of switching currents up to 3...4 A. Thanks to the small housing, the device can be made compact

Lighting circuits

The first light switch is connected instead of the existing apartment lighting switch. With the help of an automatic machine, the lighting turns on immediately, and turns off only tens of seconds after an attempt to turn off the light. This makes it possible to. When leaving the apartment, you won’t find yourself in the dark searching for your keys and inserting the key into the door lock. The light switch of the second design is designed to automatically turn on and off lighting in areas of the apartment such as a bathroom or toilet.

The considered circuits are used to automatically turn on street lighting at nightfall and automatically turn off at dawn. Some of them have original circuit and technical solutions.

The considered light switch circuits are represented by a conventional light relay, which is triggered automatically with an increase in the level of natural or artificial lighting.

There is often a need to support temperature regime any room. Previously, this required a fairly huge circuit made on analog elements; we will consider one of these for general development. Today everything is much simpler, if it is necessary to maintain the temperature in the range from -55 to +125°C, then the programmable thermometer and thermostat DS1821 microcircuit can perfectly cope with this goal

The main purpose of motion sensors is to automatically turn on or off a load or device in a certain time interval when moving biological objects appear in the sensitivity zone of the sensor. Let's consider one of the main areas of application of these sensors in controlling the lighting of objects and increasing energy efficiency.

What is a capacitive relay? This is the most common electronic relay, triggered when the capacitance between the sensor and the common wire changes. Sensitive element of many capacitive relays are high frequency generators of hundreds of kilohertz or more. If you connect an additional capacitance in parallel to the circuit of this generator, then either the frequency of the generator will change, or its oscillations will stop completely.

This is an electronic module that acts as an interface and allows for excellent electrical insulation between both low-voltage and high-voltage circuits. The device contains powerful power switches based on triacs, thyristors or power transistors. Such relays great option to replace classic electromagnetic relays, contactors and electromagnetic starters, as they provide more reliable and safe method switching

When making a homemade power supply, it became necessary to install a fan on the radiator, but the constant noise from it and energy consumption forced us to think and propose a simple regulator circuit without the use of microcontrollers, but only on analog radio components.

The electronic fuse is simple and effective way protection of various household and medical equipment from current overloads. Electronic fuses are economical, simple and reliable and, in addition, have small dimensions and are most often made on the basis of field-effect transistors

Current protection

Much is outdated Appliances has no grounding. Many people think that there is no need for it: the bodies of the devices are well insulated from the network, and they usually work with them in dry rooms. But if a breakdown or damage to the insulation suddenly occurs, faulty household appliances will become a source of serious danger. And the fuses here will not fulfill their function: they will not burn out until there is short circuit. An automatic current protection device will help you avoid electrical injuries in apartments and houses with electrical wiring without an RCD, which will disconnect electrical equipment from the network as soon as voltage appears on the housing.

Due to the constant increase in the cost of electricity, legal ways to save it become relevant. Electric lighting is rarely required in some rooms. But we often forget to turn off the light, but the light bulb continues to burn, wasting precious kilowatts.

The proposed voltage control device, the circuit of which you can assemble with your own hands, is built on the basis of the KR1006VI1 timer and an original sound effect, which is activated immediately as the voltage control says so.

These designs are used to automatically turn on outdoor lighting with the onset of darkness and, conversely, automatically turn off the lighting with the onset of dawn, which is especially important, especially in conditions of such expensive energy resources.

These mechanical transducers are used to search for vibrations and various mechanical deformations and have been used for quite some time. This design is a low-cost option for solid-state sensor applications. general purpose. The circuit uses a standard piezoelectric element to detect mechanical shock or vibration

This is an extremely easy-to-replicate water leakage sensor, which, if there is a problem with liquid getting between the plates, will connect the relay winding, which turns on any load with its contacts, for example, an electromagnetic valve that shuts off the water.

Sometimes you need to find out how much water or other conductive liquid remains in a closed container. For example, in metal barrel buried in the ground or raised to a height so that its contents cannot be determined. To solve this problem, I recommend assembling a circuit for a simple water level sensor. The device consists of only a few radio components: resistors, transistors and three LEDs.

It often happens when, leaving home, you suddenly remember, and then run to check if you left any Appliances included. But some of them can not only significantly increase your electricity bill, but also create the risk of a fire. It will help to exclude such cases simple circuit power consumption indicator.

It happens very often. that there is absolutely no one to leave home flowers for. But for an electronics engineer this is not a problem; he can build a circuit without much difficulty automatic watering indoor plants.

A Hall sensor is a magnetoelectric device that uses the Hall effect. The principle itself was discovered in 1879, when a thin gold plate with a current passed through it was placed in a magnetic field and a transverse potential difference (Hall voltage) was observed.

Disabled in time electronic device will save you from many problems. Therefore, more and more often amateur radio designs, operating at high power, are complemented by alarm systems for overheating of powerful semiconductor devices. In this technical collection we will consider not complex circuits indicators installed on the radiator.

Quite often situations arise when it is necessary for some device to continue to operate stably even in the absence of the main power supply. I suggest several repetitions simple options schemes that allow you to switch the load from regular to backup power in the event of possible power outages, this is especially true for rural areas.

To make this simple pressure sensor design with our own hands, we need the following amateur radio tools and materials: soldering iron, glue, knife, two pieces of one-sided printed circuit board, a piece of foam material or a thin layer of foam rubber sprinkled with graphite dust and installation wires.

A simple ceramic piezoelectric detector can be used to assemble a useful physical impact sensor that can be used in alarm systems on doors, windows, and to detect various shocks and vibrations.

Touch button

The touch button is an excellent alternative to standard mechanical buttons, which never wear out or become clogged, practically does not break, is resistant to aggressive liquids, does not require pressure, and is also vandal-resistant.

Heating using waste oil is now gaining popularity and those who have access to waste oil are actively installing furnaces and boilers for waste oil. And those who don’t have access buy labor for pennies. (chapter )

But we're not talking about prices).

In this article I will tell you how quickly, in an hour to an hour and a half, you can assemble a primitive “automation” for a waste oil boiler.

It is difficult to call this device automatic; it does not switch to different modes, but serves to adjust the speed of the fan blowing air into the combustion chamber and the speed of the oil pump.

Below is a test circuit assembled on a table) It all came together in a couple of hours (including a trip to auto stores). And this is a temporary solution to maintain the operation of the boiler while we are developing the main automation.

I’ll describe a little how everything works and what it consists of.

The main two units that need to be controlled are the oil pump drive (it is the motor from the car window lifter) and the cochlea - the air blower. We need to control the speed of the scroll and the oil pump to increase/decrease the oil supply to the combustion chamber, and accordingly the air supply.

Required components:

• Air blowing snail (can be used from a VAZ stove)
• Oil pump drive and the oil pump itself (gear)
• 12V power supply
• Fan for cooling automation
• Oven speed switch (from VAZ) - 3 positions
• Resistor (resistance) with the same 3 positions
• Rheostat from a car (I don’t know exactly, it seems to be for adjusting the interior lighting)
• Wires
• Clamps mom / dad
• A box for it all

The circuit is assembled

How it all works and is put together

The system has 3 modes rpm (stove speed switch): minimum, average and maximum.

Power from the 12 Volt unit goes to the mode switch, then to a resistor (resistance) with the same positions 1/2/3. From terminal 3 on the switch and on the resistor, wires go to the air volute and to an additional resistor (rheostat). The inflation volute has 3 speeds, as I already said, and the oil pump has the same 3 speeds. BUT power goes to the oil pump through a rheostat - pay attention to the photo - the red wire goes to the volute and terminals.

Thus, for the oil pump, each of the 3 modes has the ability to additionally adjust the speed of rotation with a rheostat, which allows you to very accurately dose the supply of used oil to the furnace.

The video below shows the diagram in action, but for now, detailed photos

18 ohm rheostat for smooth reduction of oil pump speed

Position switch 1/2/3 + terminal "+"

Switch internals. To mount it in the box, I had to disassemble the switch, drill holes in it and screw in screws.

The wires from the position switch go to their own 1/2/3 terminals on the resistance. The resistance heats up)))

Connection diagram for switch, resistor and motor

44 – fan motor
45 - additional resistor (used to regulate the speed of the electric motor, number 44)
46- position switch

Engine for oil pump

After I ran the entire system for a couple of hours on the stand “on the table,” I assembled everything and it turned out neat and beautiful.

To prevent the resistance from getting red hot, I installed a 12V fan into the box. Cools well

I started to worry about turning the buttons. the automation is temporary))) although the knobs can be made from polymophrus. But at that time it was 3 o’clock in the morning, and I had to leave in 4 hours, and during this time I would get some sleep... I decided to leave it as it was)

This is the boiler.

I tried to show how you can quickly assemble with your own hands a device for regulating the supply of oil and air into the combustion chamber of a waste oil boiler.

Please, who cares? this topic, unsubscribe in the comments, criticize, discuss and advise both me and everyone who is interested in the topic of heating during testing!

P.S.: in this moment automation is being developed with temperature sensors, program control and different modes combustion and protection for boilers and heaters during mining.

See about furnaces and boilers during mining in the section

UPDATE 01/18/2016: The boiler with this automation has been working continuously for 3 days at a car service center. Everything is stable. It warms up wonderfully. The most important thing is to rehearse the oil supply

Homemade products for children.

“Teach, tell”............ 5
We live in the age of automation........... 7
Before you get down to business.......... 10
For our little brothers.......... 12
What time is it?............ 16
Vehicle commanders........................ 22
How do machines “feel”......... 25
"More! Less! More!......... 33
And the machines need “muscles”.......... 34
Relay - what is it?............ 35
The time relay works............ 39
Red, yellow, green........... 45
Miracles of pneumonics......................... 50
This amazing top........... 52
From the sky on foot............... 59
In the depths of the seas and oceans........... 66
Wind and automation......................... 68
What's the weather like tomorrow?............ 76
Automation teaches................... 81
Machines that can count......... 88
Let's play with the machine......................... 99
Automated sellers........... 106
How robots learned to work.......... 112
In the world of “smart” technology............ 121

“Teach, tell”

Maybe you came across a book called “Journey to the Land of Robots.” I wrote this book several years ago. It talked about automation and that. what kind of machines there are and what they serve.

The book was published, and soon I began to receive letters from readers. Judging by the responses, the kids liked the book. Letters arrived from all over our country: from Moscow. Riga, Chelyabinsk, Krasnoyarsk. One boy even wrote from distant Chukotka.

“I really liked the book “Journey to the Land of Robots,” wrote from the city of Labinsk Krasnodar region Lena Shara-putinova. “Write a sequel to this book.”

Sasha Karyakin from the village of Turgoyak, Chelyabinsk region, also asked for the same thing. “I really like reading about technology, about space and about rockets,” he wrote. “Please continue.”

But most often the guys asked how to learn how to make various automations themselves. Almost every letter ended with questions: “How to make an automatic machine, automatic model or device? What materials should they be made from? Teach, tell."
Zhenya Zhitnov from the city of Omsk asked: “Advise how to make an automatic calculating machine. Maybe there is a book that talks about this?”

Kolya Ibragimov from Tatarstan asked to send drawings and a description of a simple robot. “I need,” wrote Kolya, “the dimensions of the parts. I would like to get the drawings as soon as possible because I want to start building during spring break.”

And again and again about the same thing. “Sasha Kulikov writes to you. I live in the 8th city of Arzamas. I'm in fourth grade. I am an average student. There are almost no twos. I liked the book, the only bad thing is that it doesn’t say anything about how you can make the automation yourself.”

There were also letters from several guys at once. “We want to know how to make models of machine guns,” said friends from the city of Kurgan Gleb, Oleg, Andrey, Seryozha and Tolya. And they signed it like this: “Orchimedes.”

The desire of the guys was clear to me. The book sparked their imagination. Automation is wonderful) But it was created by adults. I wish I could make a device that works automatically with my own hands! And not too complicated. Where can I get materials, expensive parts, different instruments? And there is still not enough knowledge. And I want to build! How to be?

A lot of letters arrived, several hundred. It was, of course, impossible to answer, help, or send drawings to all readers. And then I thought: “Really, why not write a new book in which not only continue the story about automation, but also teach children how to create simple machines with their own hands?”

Building models is not only interesting, but also very useful. I am sure that only by making a model yourself, you can clearly understand and firmly remember how a real machine, automatic device, device works.

When you become an adult, you will certainly deal with automation in one way or another: use it, set it up and configure it, or even create a new, unprecedented one. And the sooner you find out about what kind of machines exist in the world and how they work, the better. Then you will no longer look in surprise at the most complex, most ingenious machine, you will begin to work with it more confidently.
I hope that the book will help you understand the “ABC of Automation”, take your first steps in it, and become better acquainted with this very necessary and important area of ​​technology.