How to make a soldering iron temperature controller
The soldering process requires heating the soldering iron to a certain temperature. The latter is different for different materials. In order not to work on the “eye”, to perform high-quality soldering work, it is better to get a regulator that can set the temperature of the tool.
There are many circuits for regulating the temperature of the soldering iron. The simplest is published in the early 80's. in the magazine "Young Technician". It is still relevant and is used by masters in practice.
The circuit contains two circuits connected to a 220 V home network. A diode is inserted into one with a direction to the output to the soldering iron. A thyristor is installed in parallel with the diode, but with a reverse current flow direction. An adjustable resistor R1 is also connected to the thyristor, also in parallel.
In addition, a jumper is arranged from the thyristor control electrode through resistor R2 to the regulator of resistor R1. There is also a jumper through capacitor C1 between the output of the thyristor and a jumper between its control electrode and resistor R2. The capacitor is located a "plus" to this jumper.
The diode for the regulator is suitable for the brand 1N4007, in which the permissible current is 1A, and the voltage is 400 ... 600V. In the absence of such a device, you can use another, similar in characteristics. The thyristor is used brand KU101G.
Capacitor C1 is used electrolytic at 4.7 mF under a voltage of 50 ... 100V. The resistor R2 is selected in the range of 27 ... 3 Ohms, the allowable power should be 0.25 ... 0.5 watts. Variable resistor R1 brand SP-1 to 30 ... 47 Ohm; it should have a linear characteristic.
Before assembly, they engage in the conclusions of parts that are insulated and molded. For them, the thyristor uses 2 mm heat shrink tubes for insulation, and the resistor and diode use 5 mm. After the conductors are bent so as not to break the insulation.
The main to accommodate all the details in the circuit is a variable resistor, its conclusions. Before soldering, trim, shorten the conclusions of other parts. The plus terminal of the capacitor is connected to the thyristor control electrode, the resistor terminal and soldered together. The thyristor case is isolated because it is an anode.
In order for the regulator to look good, it is placed in the housing. Fits well, taken from a power supply that has a power plug.
A 10-mm hole is drilled on the outer surface (opposite to the one on which the plug is placed), a variable resistor is inserted into it with a threaded part. Secure the last with a nut.
To connect a soldering iron, two holes with a diameter of 10 mm are drilled on the upper part of the body, 19 mm apart from each other. They are provided with connectors that are secured with nuts. After all connections are completed, they are protected by shrink film.
The variable resistor shaft is provided with a handle, for the manufacture of which dielectric material is used.
Verification of the regulator made is carried out with a load of 20 ... 40-watt lamp. Turn the knob - the brightness of the lamp should change smoothly.