Most sold in Russia electrical appliances designed for a voltage of 220 volts. Those that have impulse power supply units – for example, many TVs and portable computers, working at a voltage from 110 to 220 V. sometimes, However, to power a device requires low voltage.
To lower the voltage, use an auto-transformer. You can purchase as a modern auto, and look on the markets are cheap and quite reliable autotransformers Soviet production. Due to the presence of the adjustment handle you can change the voltage in a fairly wide range. Remember that the power of the autotransformer should not be lower than the power plug of the appliance.
Lowering the supply voltage is twice as possible by including in the circuit a powerful diode. This option is especially convenient when used with a lamp having a filament. Putting a diode, you will cut off one half wave of the alternating current than lower voltage to 110 volts. The lamp will burn weaker, but will significantly increase its service life.
For smooth tension adjustment, use thyristor controller. You can assemble it yourself using one of the existing schemes. For example, this: http://sovmasteru.ru/125/
Lower the voltage by using transformer, including homemade. With decreasing voltage the number of turns in the secondary winding should be less than the number of turns in the primary winding. For the exact calculation of transformers are relatively complex formulas, but for simple household transformer you can use a simplified formula n = 50/S, where n is the number of turns for 1 volt, voltage, S is the cross – sectional area of the magnetic circuit. If you use for manufacturing of transformer W-shaped plates, the area of the magnetic circuit is determined by the product of the thickness of the plate pack to the width of his middle of the reed, in inches.
Lower the voltage by using a powerful damping resistor, but this method is uneconomical, so the resistor will dissipate significant portion of power. Instead of damping resistor in some situations, you can use the included sequentially in the network of the incandescent bulb. Changing the power of incandescent bulbs, you can change the output voltage.
Advice 2: How to lower voltage
If the voltage in the network exceeds the permissible limits, or simply unstable, in these cases it makes sense to try to lower it. For this purpose the best suitable transformer, but if you don't have it, then you can try to do it with improvised means.
You will need
- In order to lower the voltage, you'll need the damping resistor, the damping reactive impedances, thyristor regulators.
In order to obtain a significant voltage drop, you need to add a lot of resistance. Try to use this damping resistor. This device can be purchased at specialty stores, but you can collect yourself. But it must be remembered that the use of such a damping resistor, it is meaningless, a large amount of power.
If you need to lower voltage in AC systems, try to use jet quenching impedances. In conjunction with the usual condenser get the real capacitor in the power supply.
Voltage circuit without transformer can be lowered by means of a thyristor regulators. Assemble your own at home them pointless, so better to buy ready-made at a specialty store. Their electronic circuit due to the fact that on the half cycle AC you can control the delay of the thyristor, can significantly change the power supplied to the load.
If you need to reduce the voltage supply in the circuits with variable and constant current, in this case, proceed as follows. In series connect the Zener, microbore stabilizer or instead you can connect a switching Converter. The second device should be performed based on the necessary degree of lowering of the supply voltage. All of the above electronic devices work the same way as semiconductors. From this it follows that to use them better if you have a certain range of knowledge in the field of electronics.
Advice 3: How to lower current
Many appliances are designed for a certain (maximum) value of the force of the current. If the current exceeds the allowable value, such equipment can fail. To lower the current a few simple methods, consisting in a series connection with the load is active or passive (ballasting) resistors.
You will need
- automotive filament lamp, welding ballast resistor.
To reduce the charging current during charging a car battery charger from a simple rectifier connect in series with the charging circuit of the automobile lamp which will act as ballast resistance. For this solder to the conclusions of the two lamp wires, then disconnect from the battery to any wire going to the charger. In the circuit connect the lamp with wires soldered to it. Connecting in the circuit of different power lamp, change the current circuit for the charging current of the battery.
To lower the welding current when welding with the use of a simple welding transformer, having in its composition any of the regulatory devices that connect to the circuit low voltage special welding ballast resistor consists of a metal spiral, made of a material with high resistivity. Disconnect from the terminals of the welding transformer, the welding cable with the electrode holder. Connect one output of the ballast resistance to the same output of the welding transformer.
Now, inserting the end of the wire with the electrode holder between welding coils of the ballast, change the total resistance of the welding circuit, and hence the magnitude of the welding current. To reduce the welding current to move the terminal wire of the electrode holder in the direction opposite from the connected to the welding transformer to the output of ballast resistor.
To avoid electric shock all the changes in the load circuits, the connection and disconnection of the necessary elements produce only when de-energized power sources.