For various electrical work, assembly electronic circuits very often a tool such as an electric soldering iron is used. Its simplest form, which can be purchased at any hardware store, has, as a rule, an elementary design.
It includes a heating element, a sting, a handle, often wooden, and a power cable or cord. In some versions, the soldering iron can be equipped with several interchangeable tips.
The power of such a soldering iron is fixed, most often 40 or 60 watts. But it is more convenient to use a tool with the ability to adjust the power. Such models are also produced, although they are more expensive.
To perform soldering work, tools with different parameters are required. At the same time, have several soldering irons with different power and, accordingly, with a different heating temperature of the sting, it is impractical.
When mounting components on a board, the temperature of the tip is required to warm up the leads and melt the solder. Increased temperatures can lead to the combustion of individual elements, peeling of conductive tracks from the board, damage to the insulation of the wires.
At the same time, the use of a soldering iron with a lower power, and therefore with a lower tip heating temperature, which makes it possible to reach the set value, forces an increase in the exposure time to the parts and solder.
As a result, components fail from prolonged heating, and the insulation may crack over time due to the loss of mechanical properties.
Conclusion: when soldering, if heating of large areas and massive parts is required, it is necessary to increase not the temperature, but the power of the soldering iron, reducing the contact time of the tip with the outputs of the part to the minimum possible.
In this case, the solder must melt and provide reliable contact with the part, which in this mode will not undergo overheating.
Heat management
To heat a massive part to the desired temperature, the same massive soldering iron tip is needed so that the heating rate is higher than the heat removal rate of the part.
A tool that can simultaneously cope with the above tasks is a fairly powerful soldering iron with temperature control.
That is maximum power the soldering iron should be enough to heat large leads, and the temperature should be regulated within certain limits and selected in accordance with the working conditions.
Then the massive tip will have greater thermal inertia and heat the part to the required degree, without the risk of overheating.
There are several ways to adjust the soldering iron temperature:
- maximum-minimum heating (simple switch);
- dimmer adjustment;
- the use of control microcircuits in the handle of the device;
- external control unit;
- use of a hair dryer.
Using a soldering iron with adjustment, in addition to the advantages described above, you can significantly save on electricity consumption with large amounts of work performed, extend the life of the device, due to its shorter operating time at maximum power, and reduce the amount of harmful substances released during high temperature soldering.
Switches and dimmers
The simplest temperature adjustment is used in soldering irons with a switch that allows only two positions, and, accordingly, two temperature values.
At the minimum value, the soldering iron, mounted on a stand, simply keeps the tip warm, and when you press a key or button, the tip heats up to the maximum temperature at which soldering is performed.
Obviously, of the advantages described above, such a soldering iron has only the ability to save electricity. The main task of adjustment - the production of high-quality and safe installation of components - remains impossible.
The second type of soldering iron with adjustment is dimmable. Their design involves the inclusion of a dimmer in the gap of the power cable - a device that limits the power consumption of the soldering iron.
In this case, it really becomes possible to adjust the temperature of the sting, but this is done due to the voltage drop in the dimmer.
Accordingly, there can be no question of any efficiency of such a scheme. But the price of such devices is quite low and can play a decisive role in the choice.
Control units
The next type of soldering irons are already more complex devices with a power supply, in which regulation takes place using a block of semiconductors and microcircuits. Such a unit is compact and can be located in the body of the soldering iron handle, which is very convenient.
The regulator can also be located on the handle. At a fairly modest price, this is a completely acceptable option that allows you to produce high-quality soldering.
Another type of soldering iron with adjustment are tools with an external power supply. Due to the presence of these blocks, it is possible to operate the device on a rectified DC with stable voltage values.
Such a power supply also serves as a soldering iron temperature stabilizer, which will remain unchanged no matter how much the mains voltage changes. Many radio components are demanding precisely for this soldering mode.
The disadvantage of the models can be considered bulky, low mobility, but if we take into account that high-quality installation can only be done in an equipped workshop, and not “on the knee”, as they say in such cases, then you can turn a blind eye to this.
The most precise adjustment and adjustment can only be achieved with the help of a hairdryer, which preheats the board or solder to help a conventional soldering iron.
DIY temperature controller
If you have sufficient knowledge, skills and suitable materials, you can turn an ordinary 60-watt soldering iron into a device in which it will be possible to adjust the temperature of the tip, and a full and high-quality installation of radio components will be ensured.
To do this, you will need a little fine-tuning of the tool. To do this, you can use the adjustment circuits assembled on the available radio components of domestic production.
To assemble the simplest temperature controller, you can use a circuit with a variable resistor from the SP-1 series, a KU101G thyristor, any diode rated for a current of at least 1 A.
The circuit is assembled directly on the case of a variable resistor, without making a board. To accommodate the device, you can use a case from any power supply of suitable sizes. The result is a device in which a standard soldering iron is powered from the mains through a voltage regulator located in the plug.
Such a temperature controller can be used when working with a soldering iron with low power up to 60 watts.
To adjust the temperature when using a soldering iron of greater power, a more complicated device is used.
It is also assembled on parts and components of domestic production. This circuit is assembled on a board and placed in a suitably sized case.
Adjustment is carried out by a variable resistor R2 in the range from 50% to 100% of the power of the connected device. The circuit will withstand loads up to 300 watts. This will be more than enough for using a household soldering iron.
For many experienced radio amateurs, making a do-it-yourself power regulator for a soldering iron is quite common. For beginners, due to lack of experience, such designs present a certain difficulty. The main problem is the connection to the 220 V power supply. If there are errors in the circuit or installation, a rather unpleasant effect can occur, accompanied by a loud sound and a power outage. Therefore, in the absence of experience, it is advisable to first purchase the simplest device for adjusting power, and after using it and studying it, based on the experience gained, make your own, more perfect one.
An electric soldering iron is a hand tool designed to melt solder and heat the parts to be joined to the desired temperature.
To prevent accidents, you should install a circuit breaker with a small maximum allowable current and one or two sockets at the workplace. Sockets must be used for the primary connection of manufactured devices. Such a security measure will avoid a general shutdown and trips to the shield, as well as caustic comments from family members.
Stepped power regulator
To make a control device, you need to choose:
- a 220 V transformer with a power exceeding the power of the soldering iron by 20-25% (the voltage on the secondary winding must be at least 200 V);
- switch for 3-4 positions, maybe more. The maximum allowable current of the contacts must correspond to the current consumption of the soldering iron;
- case of the required size;
- cord with plug;
- socket.
You will also need fasteners, screws, screws with nuts. The secondary winding should be rewound, setting the leads to a voltage of 150 to 220 V. The number of leads will depend on the type of switch, it is desirable to distribute the voltage across the leads evenly. A switch and a voltage indicator can be installed in the power circuit to show the on/off status.
The device works as follows. If there is power on the primary winding, a voltage of the corresponding magnitude is formed on the secondary. Depending on the position of switch S1, the soldering iron will be supplied with voltage from 150 to 220 V. By changing the position of the switch, you can change the heating temperature. If there are parts, even a beginner can make such a device.
Regulator with smooth power control
This scheme allows you to assemble a compact regulator of small size with smooth control of power consumption. The device can be mounted in a wall outlet or in a charger housing from mobile phone. The device can operate with a load of up to 500 watts. For manufacturing you will need:
- thyristor KU208G or its analogues;
- diode KR1125KP2, replacement with similar diodes is possible;
- a capacitor with a capacity of 0.1 μF with a voltage of at least 160 V;
- resistor 10 kΩ;
- variable resistor 470 kOhm.
The device is quite simple, in the absence of assembly errors, it starts working immediately, without additional adjustment. It is desirable to include a voltage presence indicator and a fuse in the power circuit. The power consumption of the soldering iron is regulated by a variable resistor. As a temperature regulator for heating the soldering iron, you can use a transformer of the required power. The best option is to use a device called "LATR", but such devices have long been discontinued. In addition, they have significant weight and dimensions, they can only be used stationary.
Temperature controller
The device is a thermostat that turns off the load when the specified parameter is reached. The measuring element should be fixed on the tip of the soldering iron. To connect, you need to use a wire in heat-resistant insulation, bring them to a common connector for connecting a soldering iron. You can use separate connections, but this is inconvenient.
Temperature control is carried out by a thermistor KMT-4 or others with similar parameters. The principle of operation is quite simple. The thermal resistance and the regulating resistor are a voltage divider. Variable resistance sets a certain potential at the middle point of the divider. When heated, the thermistor changes its resistance and, accordingly, changes the set voltage. Depending on the signal level, the microcircuit outputs a control signal to the transistor.
The power supply of the low-voltage circuit is implemented through a limiting resistor and is maintained at the required level by a zener diode and a smoothing electrolytic capacitor. The transistor by the emitter current opens or closes the thyristor. The soldering iron is connected in series with the thyristor.
The maximum allowable power of the soldering iron is no more than 200 watts. If you need to use a more powerful soldering iron, you need to use diodes with a large maximum allowable current for the rectifier bridge, instead of a thyristor - a trinistor. All power elements of the circuit must be installed on heat-dissipating radiators made of aluminum or copper. The required size at a power of 2 kW for rectifier bridge diodes is at least 70 cm 2, for a trinistor 300 cm 2.
Triac soldering iron regulator
The most optimal circuit for adjusting the power of the soldering iron is a triac controller. The soldering iron is connected in series with the triac. All control elements operate on the voltage drop of the power control element. The circuit is quite simple and can be done by radio amateurs with little experience. The value of the regulating resistor can be changed depending on the required range at the output of the regulator. With a value of 100 kOhm, you can change the voltage from 160 to 220 V, at 220 kOhm - from 90 to 220 V. At the maximum operating mode of the regulator, the voltage on the soldering iron differs from the mains by 2-3 V, which distinguishes it for the better from devices with thyristors. The voltage change is smooth, you can set any value. The LED in the circuit is intended to stabilize operation, and not as an indicator. It is not recommended to replace or exclude it from the scheme. The device becomes unstable. If necessary, an additional LED can be installed as an indicator of the presence of voltage with appropriate limiting elements.
For installation, you can use a conventional installation box. Installation can be done in a hinged way or make a board. To connect a soldering iron, it is advisable to install a socket at the output of the regulator.
When installing a switch in the input circuit, you must use a device with two pairs of contacts, which will disconnect both wires. The manufacture of the device does not require significant material costs; it can be quite simply done by novice radio amateurs. Adjustment during operation consists in selecting the optimal voltage range for the operation of the soldering iron. It is performed by selecting the value of the variable resistor.
The simplest regulator circuit
The simplest temperature controller for a soldering iron can be assembled from a diode with a maximum forward current, respectively, the power of the soldering iron and the switch. The circuit is assembled very simply - the diode is connected in parallel with the contacts of the switch. Principle of operation: with open contacts, only half-cycles of one polarity enter the soldering iron, the voltage will be 110 V. The soldering iron will have a low temperature. When the contacts are closed, the soldering iron will receive a full mains voltage of 220 V. The soldering iron will warm up to the maximum temperature in a few seconds. Such a scheme will protect the tip of the tool from overheating and oxidation, and will help to significantly reduce power consumption.
The design can be anything. You can use a manual switch or install a switch with a lever system on a stand. When lowering the tool on the stand, the switch should open the contacts, close when raised.
Conclusion on the topic
For complex work it is desirable to have an optimal reliable tool that does not create unnecessary problems during work.
Industrial designs with good quality and functionality for beginners are quite expensive.
Manufacturing various devices and accessories will greatly facilitate the work and help to gain the necessary experience.
A power regulator for a soldering iron is a device that allows you to control the soldering process. The quality of this process can be significantly increased if the main parameters are taken under control. A soldering iron is a necessary tool in the household for a person who likes to do everything with his own hands.
The main characteristic of soldering is the maximum temperature at the tip of the soldering iron. The power regulator for the soldering iron ensures its change in desired mode. This allows not only to improve the quality of the metal connection, but also to increase the service life of the device itself.
What is a regulator for?
Soldering of metals is carried out due to the fact that the molten solder fills the space between the workpieces to be joined and partially penetrates into their material. The strength of the connecting seam largely depends on the quality of the melt, i.e. on its heating temperature. If the soldering iron tip has insufficient temperature, then it is necessary to increase the heating time, which can destroy the material of the parts and lead to premature failure of the device itself. Excessive heating of the filler metal leads to the formation of thermal decomposition products, which significantly reduces the quality of the weld.
The temperature of the working area of the soldering tip and the time it takes to set it depend on the power of the heating element. A smooth change in voltage allows you to choose the optimal mode of operation of the heater. Therefore, the main task that the power regulator for the soldering iron must solve is to set the required electrical voltage and maintain it during the soldering process.
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The simplest schemes
The simplest power regulator circuit for a soldering iron is shown in Fig. 1. This scheme has been known for more than 30 years and has shown itself perfectly at home. It allows you to solder parts with power control in the range of 50-100%.
Such an elementary circuit is assembled at the output ends of the variable resistor R1 and is connected by four soldering points. The positive terminal of the capacitor C1, the leg of the resistor R2 and the control electrode of the thyristor VD2 are soldered together. The thyristor case acts as an anode, so it should be isolated. The whole circuit is small and fits into a case from an unnecessary power supply of any device.
A hole with a diameter of 10 mm is drilled on the case wall, in which a variable resistor is fixed with its threaded leg. As a load, you can use any light bulb with a power of 20-40 watts. The cartridge with the light bulb is fixed in the housing, and the top of the light bulb is brought out into the hole so that the operation of the device can be controlled by its glow.
Parts that should be used in the recommended circuit: diode 1N4007 (any similar one for a current of 1 A and a voltage of up to 600 V can be used); thyristor KU101G; electrolytic capacitor with a capacity of 4.7 microfarads for a voltage of 100 V; resistor 27-33 kOhm with power up to 0.5 W; variable resistor SP-1 with a resistance of up to 47 kOhm. The soldering iron power regulator with such a circuit proved to be reliable with EPSN type soldering irons.
A simple but more modern circuit can be based on replacing the thyristor and diode with a triac, and can also be used as a load neon light bulb type MH3 or MH4. The following parts are recommended: triac KU208G; electrolytic capacitor 0.1 uF; variable resistor up to 220 kOhm; two resistors with a resistance of 1 kOhm and 300 Ohm.
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Design improvement
Power regulator assembled on the base the simplest circuit, makes it possible to maintain the soldering mode, but does not guarantee the complete stability of the process. There is a number enough simple designs, allowing to ensure stable maintenance and regulation of the temperature on the tip of the soldering iron.
The electrical part of the device can be divided into a power section and a control circuit. The power function is determined by the thyristor VS1. Voltage off electrical network(220 V) is fed into the control circuit from the anode of this thyristor.
The operation of the power thyristor is controlled on the basis of transistors VT1 and VT2. The power supply of the control system is provided by a parametric stabilizer, which includes the resistance R5 (to eliminate excess voltage) and the zener diode VD1 (to limit the increase in voltage). Variable resistor R2 provides manual voltage control at the output of the device.
The assembly of the regulator from the installation of the power section of the circuit occurs as follows. The legs of the diode VD2 are soldered to the conclusions of the thyristor. The R6 resistance legs are connected to the control electrode and the thyristor cathode, and one R5 resistance leg is connected to the thyristor anode, the second leg is connected to the VD1 zener diode cathode. The control electrode is connected to the control unit by connecting to the emitter of the transistor VT1.
The basis of the control unit is silicon transistors KT315 and KT361. With their help, the magnitude of the voltage created on the control electrode of the thyristor is set. The thyristor passes current only if an unlocking voltage is applied to its control electrode, and its value determines the strength of the transmitted current.
The entire circuit of the regulator has a small-sized design and can easily be placed in the case of a surface-mounted socket. A plastic housing should be selected to simplify drilling holes. It is advisable to assemble the power part and the control unit on different panels, and then connect them with three wires. Most best option- this is the assembly of panels on textolite coated with foil, but in practice all connections can be made with thin wires and the panels can be assembled on any insulating plate (even on thick cardboard).
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Do-it-yourself power regulator assembly
The device is assembled inside the socket housing. The output ends are connected to the socket contacts, which will make it possible to connect the soldering iron by simply inserting its plug into the socket sockets. In the case, first, a variable resistor should be fixed, and its threaded part should be brought out through the drilled hole. Then a thyristor with a mounted power unit should be placed in the housing. Finally, any free place control panel installed. From below the socket is closed by a cover. A cord with a plug is connected to the input of the power unit, which is led out of the socket housing for connection to the electrical network.
Before connecting the soldering iron, the power regulator should be checked. To do this, a voltmeter or multimeter is connected to the outputs of the device (to the socket). A voltage of 220 V is applied to the input of the device. By smoothly rotating the knob of the variable resistor, observe the change in the reading of the device. If the voltage at the output of the regulator increases smoothly, then the device is assembled correctly. The practice of using the device shows that optimal value output voltage - 150 V. This value should be fixed with a red mark indicating the position of the variable resistor knob. It is advisable to note several voltage values.
The temperature-controlled soldering iron allows you to set the required soldering temperature for heating parts, flux and solder during low-temperature soldering and tinning, depending on the materials used, and also effectively deal with the phenomenon of tip overheating. Such a tool is also called adjustable or with a power regulator. At the same time, the power ranges from 3 to 400 W, which allows you to solder microcircuits, radio components, wires, large parts made of different metals and even non-metals with the same soldering iron, ensure a tight fit, eliminate porosity, etc.
Design features and benefits
Russian and foreign manufacturers produce devices for soldering with a power regulator in 3 versions:
- with a built-in body (the tool has a small power);
- in the form of a separately located block with temperature control over a wide range;
- in soldering stations.
In the design of a low-power soldering iron, there may be a rotary dimmer (dimmer), which allows you to change the amount of electric power, then increasing it, then decreasing it. Included in the break of the supply cable. In this case, the heating temperature is controlled by the voltage drop, which results in a power drop.
The simplest voltage regulator has only 2 regulation ranges. It can be set to the maximum temperature for which it is designed to perform the soldering process and the minimum temperature that allows you to maintain the heating temperature of the tip.
By using soldering station temperature adjustment of the tool tip is carried out with high accuracy. Moreover, if the station is equipped with a hot air gun, this allows soldering without limiting the power value. Power supply and electronic system controls are in a separate block. A properly selected soldering station will provide the highest quality soldering of any electronic circuit components.
The advantage of a tool equipped with a power regulator:
- during soldering, damage to parts sensitive to the temperature of soldering is excluded and the tracks on the board do not exfoliate;
- performance is not affected by changing the brand of solder;
- flux does not smoke;
- the sting does not wear out;
- the sting does not overheat;
- the consumption of electrical energy is saved;
- extends tool life.
Purchased designs of such devices with temperature control are not cheap, their price depends on design features. Soldering stations with a hot air gun are especially expensive. Therefore, if you have certain skills and knowledge, you can make yourself an adjustable soldering iron of both the simplest and more complex designs.
A do-it-yourself power regulator for a soldering iron can be assembled according to primitive schemes and using a microprocessor with information display. It depends on the desire, qualifications and capabilities of the one who wants to make such a device, because the end result of soldering determines the quality of any device where there are electronic components. After spending a little time, you can make the available soldering iron adjustable.
The simplest wire resistor power regulator
The simplest do-it-yourself soldering iron temperature controller can be created using only 2 elements: a 25 W wire resistor with a resistance of 1 kOhm (SP5-30) and a rotary knob. The resistor must be enclosed in a housing (necessarily made of a dielectric material), securely fastening it there. It remains to put a knob on the axis of the resistor and you can smoothly adjust the power. Sockets for the plug are made on the case, or the wires of the soldering iron are soldered, and a scale is also set. The simplest device is ready.
Note! The power of such a tool does not exceed 25 watts.
Two-stage power regulator
For the manufacture of a two-stage device, you will need 2 elements: a 1N4007 rectifier diode for a current of 1 A and a switch. The product is adjusted as follows: when the switch is turned on, voltage is applied to the tip, when it is opened, it drops by half, which allows maintaining the temperature of the tip in a gentle mode, i.e. it doesn't overheat or cool down. The device has proven itself in cases where you have to take breaks in work.
The parts are connected in parallel to each other in the break of the supply wires. You can supplement the circuit with an LED by connecting it to the output of the regulator. According to the degree of brightness of the glow is determined output voltage. In this case, a limiting resistor must be present in the circuit. It turns on in series with the LED.
Dual-mode thyristor circuit
The device, manufactured according to the scheme shown in Fig. below, it is used for soldering irons with a power not exceeding 40 watts. You will need a diode with a current of not more than 1 A for a voltage of 400 V, a KU101G thyristor and a SP-1 resistor. It is assembled in a case from a charger that has failed, or any other plastic box can be used for these purposes. You can use the body of the extension socket single or tee.
For soldering irons of high power (up to 300 W), the regulator is assembled according to the scheme shown in fig. higher.
Here 2 parts (power and control) are made separately. Such a device works as follows: when the thyristor is closed (2 transistors control its operation), half the supply voltage is applied to the tip. Resistor R2 regulates the temperature in the range of 50 ÷ 100%. All parts must be placed on the board (see figure below), which is then placed in the housing of the extension socket or any other that has the right dimensions.
Note! All component leads must be insulated with heat shrink tubing to prevent short circuits.
Power regulator with information display
The figure above shows circuit diagram thermostat on the microcontroller. With its help, the power level is displayed on the indicator and the device is turned off if it long time does not work. Power information is displayed in numbers from 0 to 9, where zero means that the device is not turned on. Numbers from 1 to 9 represent the level of illumination, where 9 indicates full power operation. With 2 buttons, you can decrease or increase the voltage value.
The device has 2 modules (boards): power and digital. The regulator for the soldering iron was assembled on the widespread PIC16F628A microcontroller. Clocking is performed by a built-in oscillator at a frequency of 4 MHz. The power board has elements without transformer supply and a filter that serves to reduce interference. The digital board contains components such as a microcontroller and a seven-segment indicator.
Variable resistance controls the duration of the pulses. You can place all the elements of the circuit on one board, but this will make the device bulky. And so 2 of these boards will fit in a small case, for example, a plastic soap dish.
Power regulator using a triac
A triac is two thyristors connected together. This allows current to flow in both directions. With it, the power is adjustable from 0 to 100%. In the first case, to create a circuit, you will need only 7 parts (2 resistors, a capacitor, a diode, a dinistor, a triac and an LED), in the second - 11 parts (5 resistors, a diode bridge, 2 capacitors, 2 diodes and a triac). The diagrams show their values.
Health check
According to whatever scheme the device is made by hand, its performance must be checked. The soldering iron itself must be included in the working circuit. He is a load.
In the designs of thermostats for soldering irons, where an LED is involved in the circuits, this is easy to do. A change in the brightness of the glow indicates that the created design is working. For the rest, the test must be carried out with an incandescent lamp connected to the circuit. If there is an LED in series with a resistor in the circuit, the test is carried out using an indicator. If it does not glow, then it is necessary to carry out an adjustment, i.e. pick up a resistor.
Note! For soldering irons with a power of 100 W and higher in the regulator circuits, it is necessary to install triacs or thyristors on radiators.
power regulator made with my own hands or purchased in a distribution network, will allow during the soldering process to use the heating temperature of the tip, which will qualitatively connect the necessary components. This will avoid such troubles as damage to parts or their failure, improve the soldering process and save energy consumption.
Video
There are many models of soldering irons in stores - from cheap Chinese to expensive ones, with a built-in temperature controller, even soldering stations are sold.
Another thing is whether the same station is needed if such work needs to be done once a year, or even less often? It's easier to buy an inexpensive soldering iron. And someone at home has preserved simple but reliable Soviet instruments. A soldering iron that is not equipped with additional functionality heats to the fullest while the plug is in the network. And when turned off, it cools down quickly. An overheated soldering iron can ruin the work: it becomes impossible for them to solder something firmly, the flux evaporates quickly, the tip oxidizes and the solder rolls off it. An insufficiently heated tool can completely ruin the parts - due to the fact that the solder does not melt well, the soldering iron can be overexposed close to the parts.
To make work more comfortable, you can assemble a power regulator with your own hands, which will limit the voltage and thereby prevent the soldering iron tip from overheating.
Do-it-yourself soldering iron regulators. Overview of mounting methods
Depending on the type and set of radio components, power regulators for a soldering iron can be different sizes, with different functionality. It is possible to assemble both a small simple device in which heating is stopped and resumed by pressing a button, or an overall one with a digital indicator and program control.
Possible types of mounting in the housing: plug, socket, station
Depending on the power and tasks, the regulator can be placed in several types of housing. The simplest and most comfortable is a fork. For this you can use Charger for cell phone or the body of any adapter. It remains only to find a handle and place it in the wall of the case. If the body of the soldering iron allows (there is enough space), you can place the board with the parts in it.
Another type of housing for simple regulators is a socket. It can be either single or a tee-extension. In the latter, you can very conveniently put a pen with a scale.
There can also be several mounting options for a regulator with a voltage indicator. It all depends on the ingenuity of the radio amateur and imagination. This can be either an obvious option - an extension cord with an indicator mounted there, or original solutions.
You can even assemble a semblance of a soldering station, install a soldering iron stand on it (you can buy it separately). When installing, you must not forget about the safety rules. Parts must be insulated - for example, with heat shrink tubing.
Circuit options depending on the power limiter
The power regulator can be assembled according to different schemes. Basically, the differences are in the semiconductor part, the device that will regulate the current supply. It can be a thyristor or triac. To more accurately control the operation of a thyristor or triac, a microcontroller can be added to the circuit.
You can make a simple regulator with a diode and a switch - in order to leave the soldering iron in working condition for some (possibly long) time, preventing it from cooling down or overheating. The remaining regulators make it possible to set the temperature of the soldering iron tip more smoothly - for various needs. The assembly of the device according to any of the schemes is carried out in a similar way. The photos and videos show examples of how you can assemble a power regulator for a soldering iron with your own hands. Based on them, you can make a device with the variations you personally need and according to your own scheme.
Thyristor- a kind of electronic key. Passes current in only one direction. Unlike a diode, a thyristor has 3 outputs - a control electrode, an anode and a cathode. The thyristor opens by applying a pulse to the electrode. It closes when the direction changes or the current flowing through it stops.
Or a triac - a type of thyristor, only unlike this device, it is bilateral, it conducts current in both directions. It is, in fact, two thyristors connected together.
Triac, or triac. The main parts, the principle of operation and the method of display on the diagrams. A1 and A2 - power electrodes, G - control gate
The power regulator circuit for a soldering iron - depending on its capabilities - includes the following redo parts.
Resistor- serves to convert voltage to current and vice versa. Capacitor- the main role of this device is that it ceases to conduct current as soon as it is discharged. And it starts to conduct again - as the charge reaches the desired value. In regulator circuits, the capacitor is used to turn off the thyristor. Diode A semiconductor is an element that passes current in the forward direction and does not pass in the reverse direction. Diode subspecies - zener diode- used in devices for voltage stabilization. microcontroller- a microcircuit, with the help of which the electronic control of the device is provided. There are varying degrees of difficulty.
Circuit with switch and diode
This type of regulator is the easiest to assemble, with the fewest parts. It can be collected without a fee, by weight. The switch (button) closes the circuit - all the voltage is applied to the soldering iron, opens it - the voltage drops, the tip temperature too. At the same time, the soldering iron remains heated - this method is good for standby mode. A rectifier diode rated for a current of 1 ampere is suitable.
Assembly of a two-stage regulator on weight
- Prepare parts and tools: a diode (1N4007), a switch with a button, a cable with a plug (it can be a soldering iron cable or an extension cable - if there is a fear of ruining the soldering iron), wires, flux, solder, soldering iron, knife.
- Strip and then tin the wires.
- Tin the diode. Solder the wires to the diode. Remove the excess ends of the diode. Put on heat shrink tubing, heat it up. You can also use an electrical insulating tube - cambric. Prepare a cable with a plug in the place where it will be more convenient to mount the switch. Cut the insulation, cut one of the wires inside. Leave part of the insulation and the second wire intact. Strip the ends of the cut wire.
- Place the diode inside the switch: minus the diode - to the plug, plus - to the switch.
- Twist the ends of the cut wire and the wires connected to the diode. The diode must be inside the gap. Wires can be soldered. Connect to the terminals, tighten the screws. Assemble the switch.
Regulator with switch and diode - step by step and clearly
thyristor regulator
Regulator with power limiter - thyristor - allows you to smoothly set the temperature of the soldering iron from 50 to 100%. In order to expand this scale (from zero to 100%), a diode bridge must be added to the circuit. The assembly of regulators on both the thyristor and the triac performs in a similar way. The method can be applied to any device of this type.
Assembling a thyristor (triac) regulator on a printed circuit board
- Make a wiring diagram - outline the convenient location of all the parts on the board. If the board is purchased, the wiring diagram is included.
- Prepare parts and tools: a printed circuit board (you need to make it in advance according to the diagram or buy it), radio components - see the specification for the diagram, wire cutters, a knife, wires, flux, solder, a soldering iron.
- Place the parts on the board according to the wiring diagram.
- Bite off the excess ends of the parts with wire cutters.
- Lubricate with flux and solder every detail - first resistors with capacitors, then diodes, transistors, thyristor (triac), dinistor.
- Prepare the case for assembly.
- Strip, tin the wires, solder to the board according to the wiring diagram, install the board into the case. Insulate the wire connections.
- Check the regulator - connect to an incandescent lamp.
- Assemble the device.
Scheme with a low-power thyristor
The thyristor of small power is inexpensive, takes up little space. Its feature is in increased sensitivity. To control it, a variable resistor and a capacitor are used. Suitable for devices up to 40W.
Specification
Scheme with a powerful thyristor
The thyristor is controlled by two transistors. The power level is controlled by resistor R2. The regulator, assembled according to this scheme, is designed for loads up to 100 watts.
Specification
| Name | Designation | Type/Nominal |
| Capacitor | C1 | 0.1uF |
| Transistor | VT1 | KT315B |
| Transistor | VT2 | KT361B |
| Resistor | R1 | 3.3 kOhm |
| variable resistor | R2 | 100 kOhm |
| Resistor | R3 | 2.2 kOhm |
| Resistor | R4 | 2.2 kOhm |
| Resistor | R5 | 30 kOhm |
| Resistor | R6 | 100 kOhm |
| Thyristor | VS1 | KU202N |
| zener diode | VD1 | D814V |
| rectifier diode | VD2 | 1N4004 or KD105V |
Assembling a thyristor regulator according to the above diagram in a case - clearly
Assembly and testing of the thyristor regulator (review of parts, installation features)
Scheme with a thyristor and a diode bridge
Such a device allows you to adjust the power from zero to 100%. The scheme uses a minimum of details.
Specification
The regulator on the triac
Triac regulator circuit with a small number of radio components. Allows you to adjust the power from zero to 100%. The capacitor and resistor will ensure accurate operation of the triac - it will open even at low power.
Assembling the triac regulator according to the above diagram step by step
Triac regulator with diode bridge
The scheme of such a regulator is not very complicated. In this case, the load power can be varied in a fairly large range. With a power of more than 60 W, it is better to put the triac on the radiator. At lower power, cooling is not needed. The assembly method is the same as in the case of a conventional triac regulator.
Before installation assembled regulator can be checked with a multimeter. You need to check only with a connected soldering iron i.e. under load. We rotate the knob of the resistor - the voltage changes smoothly.
In the regulators, assembled according to some of the schemes given here, there will already be indicator lights. They can be used to determine if the device is working. For the rest, the easiest test is to connect an incandescent bulb to the power regulator. Changing the brightness will clearly reflect the level of the applied voltage.
Regulators where the LED is in series with a resistor (as in the low-power thyristor circuit) can be adjusted. If the indicator is off, you need to choose the value of the resistor - take it with a lower resistance until the brightness is acceptable. Too high brightness cannot be achieved - the indicator will burn out.
As a rule, adjustment with a properly assembled circuit is not required. With the power of a conventional soldering iron (up to 100 W, average power - 40 W), none of the regulators assembled according to the above schemes requires additional cooling. If the soldering iron is very powerful (from 100 W), then the thyristor or triac must be installed on the radiator to avoid overheating.
You can assemble the power regulator for the soldering iron with your own hands, focusing on your own capabilities and needs. There are many variants of regulator circuits with various power limiters and different controls. Here are some of the simpler ones. A small overview of the cases in which parts can be mounted will help you choose the format of the device.
