Circuit knowledge

Here is a simple but inexpensive inverter for using a small soldering iron (25W, 35W, etc) In the absence of mains supply. It uses eight transistors and a few resistors and capacitors. Transistors Q1 and Q2 (each BC547) form an astable multivibrator that produces 50Hz signal.

The complementary outputs from the collectors of transistors Q1 and Q2 are fed to pnp Darlington driver stages formed by transistor pairs Q3-Q5 and Q4-Q6 (utilising BC558 and BD140). The outputs from the drivers are fed to transistors Q7 and Q8 (each 2N3055) connected for push-pull operation.  Use suitable heat-sinks for transistors Q5 through Q8. A 230V AC primary to 12V-0-12V, 4.5A secondary transformer (T1) is used.

The centre-tapped terminal of the secondary of the transformer is connected to the battery (12V, 7Ah), while the other two terminals of the secondary are connected to the collectors of power transistors T7 and T8, respectively. When you power the circuit using switch S1, transformer X1 produces 230V AC at its primary terminal. This voltage can be used to heat your soldering iron. Assemble the circuit on a generalpurpose PCB and house in a suitable cabinet.

Connect the battery and transformer with suitable current-carrying wires. On the front panel of the box, fit power switch S1 and a 3-pin socket for connecting the soldering iron. Note that the ratings of the battery, transistors T7 and T8, and transformer may vary as these all depend on the load (soldering iron).

This is certainly a low-cost 20W/40W fluorescent lamp inverter schema project. Even so the maximum effective would be to make use of a 40 watt tube (or two 20 watt tubes in series). It is a schema you may put collectively from junk box parts or assemble from a kit. It certainly is quite easy to construct and no need printed schema board. The transformer is hand-wound on a ferrite rod (from an old transistor radio) and the winding wire could be salvaged from an old transformer. We’re intentionally maintaining bills down to confirm how cheaply it could be put together.

Dependant upon your stock of components, the cost could vary from $3.00 to about $15.00 and in case the wires from the transformer are soldered to the ends of the tube(s), you are able to make a free-standing light that can be set-up in the garden to light up a dark place without having the worry of operating 240v wiring. The cost of powering the schema is about 22 watts and this will make the same light output as a 60 watt globe.

Using a regular fluoro operating on the 240v mains, a ballast (or choke) is required in series with the tube to limit the current after the tube has “struck”. This ballast dissipates about 10-20 watts for a 20 watt tube and lowers the effectiveness of this schema. In case the ballast is replaced with an electronic schema and high-frequency transformer, the losses are lower than 5 watts. In addition, if we tend not to drive the tube as tough as the 240v type we are able to get even better effectiveness.

This Semi Low Power Inverter Circuit Diagram uses only 9 parts and turns 10 to 16 Vdc into 60-Hz, 115-V square-wave power to operate ac equipment up to 25 W. The first section of the 556 timer chip is wired as an stable oscillator with R2 and C1 setting the frequency. The output is available at pin 5. The second section is wired as a phase inverter. 

That output is available at pin 9. Resistors R3 and R4 keep output transistors Q1 and Q2 from loading down the oscillator. The two transistors drive the transformer push-pull fashion. When one transistor is biased-on, the other is cut-off. The transformer is a 120 V/18 VCT unit that is connected backwards, so that it steps the voltage up rather than down. Oscillator schema U1, R1, R2, and C1 operates from about 4 to 16 V with a very ~stable output.

This inverter uses PWM (Pulse Width Modulator) with type IC SG3524. IC serves as a oscillator 50Hz, as a regulator of the desired output voltage. Input power ranging from 250W up to 5000W output and has. Following a series INVERTER 5000W with PWM (Pulse Width Modulator).