Soldering iron temperature controller on a transistor. Soldering iron with temperature control. Scheme with a thyristor and a diode bridge

16.01.2022

In order to simplify soldering work and improve their quality, a simple temperature controller for a soldering iron tip may come in handy for a home craftsman or radio amateur. It was this regulator that the author decided to assemble for himself.

For the first time, the scheme of such a device was noticed by the author in the magazine "Young Technician" in the early 80s. According to these schemes, the author collected several copies of such regulators and still uses them.

To assemble the soldering iron tip temperature control device, the author needed the following materials:
1) 1N4007 diode, although any other diode is suitable for which a current of 1 A and a voltage of 400-60 V are acceptable
2) thyristor KU101G
3) 4.7 microfarad electrolytic capacitor whose operating voltage is from 50 V to 100 V
4) resistor 27 - 33 kOhm, the power of which is from 0.25 to 0.5 watts
5) variable resistor 30 or 47 kOhm SP-1 with a linear characteristic
6) power supply housing
7) a pair of connectors with holes for pins with a diameter of 4 mm

Description of the manufacture of a device for regulating the temperature of the soldering tip:

In order to better understand the scheme of the device, the author drew how the placement of parts and their interconnection is carried out.

Before starting the assembly of the device, the author isolated and molded the leads of the parts. Tubes about 20 mm long were put on the conclusions of the thyristor, and tubes 5 mm long were put on the terminals of the resistor and diode. To make it more convenient to work with the leads of parts, the author suggested using colored PVC insulation, which can be removed from any suitable wires, and then attached to heat shrink. Further, using the above figure and photographs as a visual aid, it is necessary to carefully bend the conductors and not damage the insulation. Then all the parts are attached to the terminals of a variable resistor, while being combined into a circuit that contains four solder points. In the next step, the conductors of each of the components of the device are inserted into the holes on the terminals of the variable resistor and carefully soldered. After that, the author shortened the conclusions of the radioelements.

Then the author connected together the leads of the resistance, the control electrode of the thyristor and the positive wire of the capacitor and fixed them with a soldering iron. Since the thyristor case is an anode, the author decided to isolate it for safety.

To give the design a finished look, the author used the power supply case with a power plug. To do this, a hole was drilled on the upper edge of the case. The hole diameter was 10 mm. The threaded part of the variable resistor was installed in this hole and fixed with a nut.

To connect the load, the author used two connectors with holes for pins with a diameter of 4 mm. To do this, the centers of the holes were marked on the case, the distance between which was 19 mm, and connectors were installed in the drilled holes with a diameter of 10 mm, which the author also fixed with nuts. Next, the author connected the plug of the case to the assembled circuit and the output connectors, and protected the soldering points with heat shrink.

Then the author selected a handle of insulating material of the desired shape and size, suitable in size, in order to close both the axle and the nut with it.
Then the author assembled the case and securely fixed the regulator knob.

Then I started testing the device. As a load for testing the regulator, the author used an incandescent lamp of 20-40 watts. It is important that when the knob is turned, the brightness of the lamp changes smoothly enough. The author managed to achieve a change in the brightness of the lamp from half to full heat. Thus, when working with soft solders, for example POS-61, using the EPSN 25 soldering iron, 75% of the power is enough for the author. In order to obtain such indicators, the regulator knob should be located approximately in the middle of the stroke.

When working with a soldering iron, it often becomes necessary to adjust its power. This is necessary when choosing the optimal temperature of the soldering iron tip, since at too low a temperature the solder does not melt well, and at too high a temperature, the tip overheats and destroys it, and the soldering is of poor quality.

In addition, an amateur often has to perform various soldering jobs that require different soldering iron power.

To control the power, a large number of different schemes are used. Examples are:

with a variable resistor;
with resistor and diode;
with a microcircuit and a field effect transistor;
with thyristor.

The simplest power regulator for a soldering iron is a circuit with variable resistor. In this embodiment, a variable resistor is connected in series with the soldering iron. The disadvantage of this scheme is that a lot of power is dissipated on the element, which goes into heat. In addition, a high power variable resistor is a rather scarce element.

More complex is the method using resistor and rectifying diode. This scheme has three modes of operation. In maximum mode, the soldering iron is connected directly to the network. In operating mode, a resistor is connected in series with the tool, which determines the optimal mode of operation.

When turned on in standby mode, the soldering iron is powered through a diode, which cuts off one half-cycle of the AC mains. As a result, the power of the soldering iron is halved.

Using microchips and field effect transistor soldering iron power adjustment is provided not only to the smaller, but also to the larger side. At the same time, a rectifier bridge is involved in the circuit, at the output of which the voltage can reach 300 V. In series with, a powerful field-effect transistor of the KP707V2 type is included in the package.

In addition to the temperature controller, the soldering tool itself is assembled from improvised parts. It's not hard to learn. It is only necessary to find all the constituent elements and follow a certain assembly order.

One of the most common tools for household work related to electricity is. Everyone knows how to use it, but there are some nuances in the operation of different types of such screwdrivers.

The power of the soldering iron is controlled pulse-width method. To do this, pulses with an average frequency of 30 kHz are applied to the gate, generated using a multivibrator assembled on a K561LA7 microcircuit. By changing the generation frequency, you can adjust the voltage on the soldering iron from ten to 300 V. As a result, the current of the tool and the temperature of its heating change.

The most common option used to adjust the power of a soldering iron is a circuit using thyristor.

It consists of a small number of non-deficient elements, which makes it possible to design such a regulator in very small dimensions.

Features of the most optimal controller - with a thyristor

The composition of a typical thyristor circuit includes the elements shown in the table.

The power diode VD2 and the thyristor VS1 in the circuit are connected in series with the load - a soldering iron. The voltage of one half-cycle is directly supplied to the load. The second half-cycle is controlled by a thyristor, the electrode of which receives a control signal.

On transistors VT1, VT2, capacitor C1, resistors R1, R2, a sawtooth voltage circuit is implemented, which is applied to the control electrode of the thyristor. Depending on the position of the resistance value of the adjusting resistor R2, the thyristor opening time changes for the passage of the second half-cycle of the alternating voltage.

As a result of this, there is a change in the average voltage over the period, and, consequently, the power.

Resistor R5 dampens the excess voltage, and the zener diode VD1 is designed to provide power to the control circuit. The rest of the components are designed to ensure the modes of operation of the structural elements. To read the characteristics of such devices is.

Do-it-yourself device design

As follows from the consideration of the circuit, it consists of a power section, which should be carried out using surface mounting, and a control circuit on a printed circuit board.

Creation printed circuit board includes making a board drawing. For this, in domestic conditions, the so-called LUT is usually used, which means laser-ironing technology. The PCB manufacturing method includes the following steps:

creating a drawing;
transferring the pattern to the board blank;
etching;
cleaning;
drilling holes;
tinning of conductors.

Sprint Layout is the most commonly used program for creating a board image. After receiving a drawing with a laser printer, it is transferred to a foil getinax using a heated iron. Then the excess foil is etched with ferric chloride and the pattern is cleaned. Holes are drilled in the right places, and the conductors are tinned. The elements of the control circuit are placed on the board and they are desoldered (there are certain recommendations -).

Assembly power unit the circuit includes connecting resistors R5, R6 and diode VD2 to the thyristor.

Last build step– placement of the power section and the control circuit board in the housing. The order of placement in the housing depends on its type.

In the case of installation of open wiring, so as not to be distracted by additional purchases in the store, you can make. The difference between such devices is only in the functional component - the lighting switching circuit.

You can read more about the features of pass-through switches in. In addition, other types of switches are gaining more and more popularity in modern lighting control systems - for example,.

Since the dimensions of the elements are small and there are not many of them, then, for example, a plastic socket can be used as a housing. The largest place there is occupied by a variable adjustment resistor and a powerful thyristor. Nevertheless, as experience shows, all elements of the circuit, together with the printed circuit board, fit into such a case.

Checking and adjusting the circuit

To check the circuit, a soldering iron and a multimeter are connected to its output. By turning the knob of the regulator, it is necessary to check the smoothness of the change in the output voltage.

An additional element of the regulator can be an LED.

By turning on the LED at the output of the regulator, you can visually determine the increase and decrease in the output voltage by the brightness of the glow. In this case, a limiting resistor must be installed in series with the light source.

conclusions:

In the process of working with a soldering iron, it is often necessary to adjust its power.
There are numerous schemes for adjusting the power of a soldering iron with a resistor, transistor, thyristor.
The power control circuit of the soldering iron with a thyristor is simple, has small dimensions and can be easily assembled by hand.

Video with tips for assembling a soldering iron temperature controller with your own hands

A soldering iron is a tool that a home craftsman cannot do without, but the device is not always satisfied. The fact is that a conventional soldering iron, which does not have a thermostat and, as a result, heats up to a certain temperature, has a number of disadvantages.

Soldering iron diagram.

If during short work it is quite possible to do without a temperature controller, then for a conventional soldering iron, which has been connected to the network for a long time, its shortcomings are fully manifested:

solder rolls off an overheated tip, as a result of which the soldering is fragile;
scale forms on the sting, which often has to be cleaned;
the working surface is covered with craters, and they must be removed with a file;
it is uneconomical - in the intervals between soldering sessions, sometimes quite long, it continues to consume rated power from the network.

The thermostat for the soldering iron allows you to optimize its operation:

Figure 1. Scheme of the simplest thermostat.

the soldering iron does not overheat;
it becomes possible to choose the temperature value of the soldering iron, which is optimal for a particular job;
during breaks, it is enough to reduce the heating of the tip using the temperature controller, and then quickly restore the required degree of heating at the right time.

Of course, LATR can be used as a thermostat for a 220 V soldering iron, and a KEF-8 power supply for a 42 V soldering iron, but not everyone has them. Another way out is to use an industrial dimmer as a temperature controller, but they are not always commercially available.

Do-it-yourself temperature regulator for a soldering iron

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The simplest thermostat

This device consists of only two parts (Fig. 1):

Pushbutton switch SA with NC contacts and latching.
Semiconductor diode VD, designed for a forward current of about 0.2 A and a reverse voltage of at least 300 V.

Figure 2. Scheme of a thermostat operating on capacitors.

This temperature controller works as follows: in the initial state, the contacts of the switch SA are closed and the current flows through the heating element of the soldering iron during both positive and negative half-cycles (Fig. 1a). When the SA button is pressed, its contacts open, but the semiconductor diode VD passes current only during positive half-cycles (Fig. 1b). As a result, the power consumed by the heater is halved.

In the first mode, the soldering iron warms up quickly, in the second mode, its temperature decreases slightly, overheating does not occur. As a result, you can solder in fairly comfortable conditions. The switch, together with the diode, is connected to the break in the supply wire.

Sometimes the SA switch is mounted on a stand and is triggered when the soldering iron is placed on it. During the breaks between soldering, the switch contacts are open, the heater power is reduced. When the soldering iron is lifted, the power consumption increases and it quickly heats up to operating temperature.

Capacitors can be used as a ballast resistance, with which you can reduce the power consumed by the heater. The smaller their capacitance, the greater the resistance to the flow of alternating current. A diagram of a simple thermostat operating on this principle is shown in fig. 2. It is designed to connect a 40W soldering iron.

When all switches are open, there is no current in the circuit. By combining the position of the switches, three degrees of heating can be obtained:

Figure 3. Schemes of triac thermostats.

The lowest degree of heating corresponds to the closing of the contacts of the switch SA1. In this case, capacitor C1 is connected in series with the heater. Its resistance is quite high, so the voltage drop across the heater is about 150 V.
The average degree of heating corresponds to the closed contacts of switches SA1 and SA2. Capacitors C1 and C2 are connected in parallel, the total capacitance is doubled. The voltage drop across the heater increases to 200 V.
When the SA3 switch is closed, regardless of the state of SA1 and SA2, the full mains voltage is applied to the heater.

Capacitors C1 and C2 are non-polar, designed for a voltage of at least 400 V. To achieve the required capacity, several capacitors can be connected in parallel. Through resistors R1 and R2, the capacitors are discharged after the regulator is disconnected from the network.

There is another version of a simple regulator, which is not inferior to electronic ones in terms of reliability and quality of work. To do this, a variable wire resistor SP5-30 or some other one with a suitable power is switched on in series with the heater. For example, for a 40-watt soldering iron, a resistor rated for 25 W and having a resistance of about 1 kOhm is suitable.

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Thyristor and triac thermostat

The operation of the circuit shown in fig. 3a, the operation of the previously analyzed circuit in Fig. 1. Semiconductor diode VD1 passes negative half-cycles, and during positive half-cycles, the current passes through the thyristor VS1. The proportion of the positive half-cycle, during which the thyristor VS1 is open, ultimately depends on the position of the variable resistor R1 slider, which regulates the current of the control electrode and, consequently, the firing angle.

Figure 4. Scheme of a triac thermostat.

In one extreme position, the thyristor is open during the entire positive half-cycle, in the second it is completely closed. Accordingly, the power dissipated on the heater varies from 100% to 50%. If you turn off the VD1 diode, then the power will change from 50% to 0.

In the diagram shown in fig. 3b, a thyristor with an adjustable firing angle VS1 is included in the diagonal of the diode bridge VD1-VD4. As a result, the regulation of the voltage at which the thyristor is unlocked occurs both during the positive and during the negative half-cycle. The power dissipated on the heater changes when the variable resistor R1 slider is turned from 100% to 0. You can do without a diode bridge if you use a triac instead of a thyristor as a control element (Fig. 4a).

For all its attractiveness, a thermostat with a thyristor or triac as a control element has the following disadvantages:

with an abrupt increase in current in the load, strong impulse noise occurs, which then penetrates into the lighting network and the air;
distortion of the mains voltage shape due to the introduction of non-linear distortions into the network;
power factor reduction (cos ϕ) due to the introduction of a reactive component.

To minimize impulse noise and non-linear distortion, it is desirable to install network filters. The simplest solution is a ferrite filter, which is a few turns of wire wound around a ferrite ring. Such filters are used in most switching power supplies for electronic devices.

A ferrite ring can be taken from the wires connecting the computer system unit to peripheral devices (for example, to a monitor). Usually they have a cylindrical thickening, inside of which there is a ferrite filter. The filter device is shown in fig. 4b. The more turns, the higher the quality of the filter. The ferrite filter should be placed as close as possible to the noise source - thyristor or triac.

In devices with a smooth change in power, the regulator slider should be calibrated and its position should be marked with a marker. When setting up and installing, you must disconnect the device from the network.

The schemes of all the above devices are quite simple and they can be repeated by a person with minimal skills in assembling electronic devices.

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, a circuit breaker with a small maximum allowable current and one or two sockets should be installed 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 socket or a mobile phone charger. 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 low-voltage circuit is powered through a limiting resistor and 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.

Many soldering irons are sold without a power regulator. When connected to the network, the temperature rises to the maximum and remains in this state. To adjust it, you need to disconnect the device from the power source. In such soldering irons, the flux instantly evaporates, oxides are formed and the tip is in a constantly polluted state. It has to be cleaned frequently. Soldering large components requires high temperatures, while small parts can be burned. To avoid such problems, power regulators are made.

How to make a reliable power regulator for a soldering iron with your own hands

The power controls help control how hot the soldering iron is.

Connecting a ready-made heating power controller

If you do not have the opportunity or desire to mess with the manufacture of the board and electronic components, then you can buy a ready-made power regulator in a radio store or order it on the Internet. The regulator is also called a dimmer. Depending on the power, the device costs 100-200 rubles. You may need to modify it a little after purchase. Dimmers up to 1000 W are usually sold without a cooling radiator.

Power regulator without heatsink

And devices from 1000 to 2000 W with a small heatsink.

Power regulator with small heatsink

And only the more powerful ones are sold with larger heatsinks. But in fact, a dimmer from 500 W should have a small cooling radiator, and from 1500 W large aluminum plates are already installed.

Chinese power regulator with a large heatsink

Keep this in mind when connecting the device. If necessary, install a powerful cooling radiator.

Improved power regulator

For correct connection of the device to the circuit, look at the reverse side of the printed circuit board. The IN and OUT terminals are indicated there. The input is connected to a power outlet, and the output to a soldering iron.

Designation of input and output terminals on the board

The controller is mounted in different ways. To implement them, you do not need special knowledge, and from the tools you only need a knife, a drill and a screwdriver. For example, you can include a dimmer in a soldering iron power cord. This is the easiest option.

Cut the soldering iron cable into two pieces.
Connect both wires to the board terminals. Screw the segment with the fork to the entrance.
Choose a plastic case that is suitable in size, make two holes in it and install the regulator there.

Another easy way: you can install the regulator and socket on a wooden stand.

Not only a soldering iron can be connected to such a regulator. Now consider a more complex, but compact version.

Take a large plug from an unnecessary power supply.
Remove the existing board with electronic components from it.
Drill holes for the dimmer knob and two terminals for the input plug. Terminals are sold in the radio shop.
If your regulator has indicator lights, make holes for them too.
Install the dimmer and terminals into the plug housing.
Take a portable outlet and plug it in. Insert a plug with a regulator into it.

This device, like the previous one, allows you to connect different devices.

Homemade two-stage temperature controller

The simplest power regulator is a two-stage one. It allows you to switch between two values: the maximum and half of the maximum.

Two stage power regulator

When the circuit is open, current flows through diode VD1. The output voltage is 110 V. When the circuit is closed with switch S1, the current bypasses the diode, since it is connected in parallel and the output voltage is 220 V. Select the diode according to the power of your soldering iron. The output power of the regulator is calculated by the formula: P = I * 220, where I is the diode current. For example, for a diode with a current of 0.3 A, the power is calculated as follows: 0.3 * 220 \u003d 66 W.

Since our block consists of only two elements, it can be placed in the body of the soldering iron using surface mounting.

Solder the parts of the microcircuit in parallel to each other directly using the legs of the elements themselves and the wires.
Connect to chain.
Fill everything with epoxy, which serves as an insulator and protection against displacement.
Make a hole in the handle for the button.

If the case is very small, then use the switch for the lamp. Mount it in the soldering iron cord and insert a diode parallel to the switch.

Light switch

On triac (with indicator)

Consider a simple triac regulator circuit and make a printed circuit board for it.

Triac power regulator

PCB manufacturing

Since the circuit is very simple, it makes no sense to install a computer program for processing electrical circuits because of it alone. Moreover, special paper is needed for printing. And not everyone has a laser printer. Therefore, let's go by the simplest way of manufacturing a printed circuit board.

Take a piece of textolite. Cut off the required size for the chip. Sand the surface and degrease.
Take a marker for laser discs and draw a diagram on the textolite. In order not to be mistaken, first draw with a pencil.
Next, let's start etching. You can buy ferric chloride, but after it the sink is poorly washed. If you accidentally drip on clothes, stains will remain that cannot be completely removed. Therefore, we will use a safe and cheap method. Prepare a plastic container for the solution. Pour in 100 ml of hydrogen peroxide. Add half a tablespoon of salt and a sachet of citric acid to 50 g. The solution is made without water. You can experiment with proportions. And always make a fresh solution. Copper should be all etched. This takes about an hour.
Rinse the board under a stream of well water. Dry. Drill holes.
Wipe the board with an alcohol - rosin flux or a regular solution of rosin in isopropyl alcohol. Take some solder and tin the tracks.

To apply the scheme to the textolite, you can make it even easier. Draw a diagram on paper. Glue it with adhesive tape to the cut out textolite and drill holes. And only after that draw the circuit with a marker on the board and poison it.

Mounting

Prepare all the necessary components for installation:

solder coil;
pins in the board;
triac bta16;
100nF capacitor;
2 kΩ fixed resistor;
dinistor db3;
variable resistor with a linear dependence of 500 kOhm.

Proceed with the installation of the board.

Bite off four pins and solder them to the board.
Install the dinistor and all other parts except for the variable resistor. Solder the triac last.
Take a needle and a brush. Clean the gaps between the tracks to remove possible short circuits.
Take an aluminum radiator to cool the triac. Drill a hole in it. The triac with a free end with a hole will be fixed to an aluminum radiator for cooling.
Clean the area where the element is attached with fine sandpaper. Take the KPT-8 heat-conducting paste and apply a small amount of paste on the radiator.
Secure the triac with a screw and nut.
Gently bend the board so that the triac takes a vertical position with respect to it. To keep the design compact.
Since all parts of our device are under mains voltage, we will use a handle made of insulating material for adjustment. It is very important. Metal holders are life-threatening here. Put the plastic handle on the variable resistor.
With a piece of wire, connect the extreme and middle terminals of the resistor.
Now solder two wires to the extreme conclusions. Connect the opposite ends of the wires to the corresponding terminals on the board.
Take an outlet. Remove the top cover. Connect two wires.
Solder one wire from the socket to the board.
And connect the second to the wire of a two-core network cable with a plug. The power cord has one free core. Solder it to the corresponding pin on the PCB.

In fact, it turns out that the regulator is connected in series to the load power circuit.

Scheme of connecting the regulator to the circuit

If you want to install an LED indicator in the power regulator, then use a different scheme.

Power Regulator Circuit with LED Indicator

Diodes added here:

VD 1 - diode 1N4148;
VD 2 - LED (operation indication).

The triac circuit is too bulky to be included in a soldering iron handle, as is the case with a two-stage regulator, so it must be connected externally.

Installation of the structure in a separate housing

All elements of this device are under mains voltage, so you can not use a metal case.

Take a plastic box. Outline how the board with the radiator will be placed in it and on which side to connect the power cord. Drill three holes. The two extreme ones are needed to mount the socket, and the middle one is for the radiator. The head of the screw to which the radiator will be attached must be hidden under the socket for electrical safety reasons. The radiator has contact with the circuit, and it has direct contact with the network.
Make another hole on the side of the case for the network cable.
Install the radiator mounting screw. Put the washer on the reverse side. Screw on the radiator.
Drill an appropriately sized hole for the potentiometer, that is, for the knob of the variable resistor. Insert the part into the body and secure with a regular nut.
Lay the socket on the case and drill two holes for the wires.
Fix the socket with two M3 nuts. Insert the wires into the holes and tighten the cover with a screw.
Route the wires inside the case. Solder one of them to the board.
The other is to the core of the network cable, which is first inserted into the plastic case of the regulator.
Insulate the joint with electrical tape.
Connect the free wire of the cord to the board.
Close the case with a cap and tighten with screws.

The power regulator is connected to the network, and the soldering iron is connected to the regulator outlet.

Video: installation of a regulator circuit on a triac and assembly in a housing

On thyristor

The power regulator can be made on the bt169d thyristor.

Thyristor power regulator

Circuit components:

VS1 - thyristor BT169D;
VD1 - diode 1N4007;
R1 - 220k resistor;
R3 - 1k resistor;
R4 - 30k resistor;
R5 - resistor 470E;
C1 - capacitor 0.1mkF.

Resistors R4 and R5 are voltage dividers. They reduce the signal, since the bt169d thyristor is low-power and very sensitive. The circuit is assembled in the same way as a regulator on a triac. Since the thyristor is weak, it will not overheat. Therefore, a cooling radiator is not needed. Such a circuit can be mounted in a small box without an outlet and connected in series with the soldering iron wire.

Power regulator in a small package

Scheme on a powerful thyristor

If in the previous circuit we replace the thyristor bt169d with a more powerful ku202n and remove the resistor R5, then the output power of the regulator will increase. Such a regulator is assembled with a thyristor radiator.

Scheme on a powerful thyristor

On the microcontroller with indication

A simple power regulator with light indication can be made on a microcontroller.

Regulator circuit on the ATmega851 microcontroller

Prepare the following components to assemble it:

Using the S3 and S4 buttons, the power and brightness of the LED will change. The circuit is assembled similarly to the previous ones.

If you want the instrument to show the percentage of output power instead of a simple LED, then use a different circuit and appropriate components, including a numeric indicator.

Regulator circuit on the PIC16F1823 microcontroller

The circuit can be mounted in a socket.

The regulator on the microcontroller in the socket

Checking and adjusting the thermostat block circuit

Before connecting the unit to the instrument, test it.

Take the assembled circuit.
Connect it to the mains cable.
Connect a 220 lamp to the board and a triac or thyristor. Depending on your schema.
Plug the power cord into a socket.
Turn the variable resistor knob. The lamp should change the degree of incandescence.

The circuit with the microcontroller is checked in the same way. Only the digital indicator will still show the percentage of output power.

To adjust the circuit, change the resistors. The more resistance, the less power.

Often you have to repair or modify various devices using a soldering iron. The operation of these devices depends on the quality of soldering. If you purchased a soldering iron without a power regulator, be sure to install it. With constant overheating, not only electronic components will suffer, but also your soldering iron.