A very effective pure sine wave inverter circuit can be made using the IC 4047 and a couple IC 555 together with a few other passive components. I have explained the details below.
The Circuit Concept
In the previous post I explained the main specifications and datasheet of the IC 4047 where I have explained how the IC could be configured into a simple inverter circuit without involving any external oscillator circuit.
In this article we carry on the design a little ahead and learn how it can be enhanced into a pure sine wave inverter circuit using a couple of additional ICs 555 along with the existing IC 4047.
The IC 4047 section remains basically the same and is configured in its normal free running multivibrator mode with its output extended with the mosfet/transformer stage for the required 12V to the AC mains conversion.
How the IC 4047 Functions
The IC 4047 generates the usual square waves to the connected mosfets creating a mains output at the secondary of the transformer which is also in the form of square wave AC.
The integration of the two 555 IC to the above stage completely transforms the output into a pure sine wave AC. The following explanation reveals the secret behind the IC555 functioning for the above.
Referring to the below shown IC 4047 pure sine wave inverer circuit (designed by me), we can see two identical IC 555 stages, wherein the left section functions as a current controlled sawtooth generator while the right hand side section as a current controlled PWM generator.
The triggering of both the 555 ICs are derived from the oscillator output readily available across pin#13 of IC 4047. This frequency would be 100Hz if the inverter is intended for 50Hz operations, and 120Hz for 60Hz applications.
Using IC 555 for the PWM Generation
The left 555 section generates a constant sawtooth wave across its capacitor which is fed to the modulating input of the IC2 555 where this sawtooth signal is compared with the high frequency signal from pin3 of IC1 555 creating the required pure sine wave equivalent PWM at pin#3 of 555 IC2.
The above PWM is directly applied to the gates of the mosfets. so that the square pulses here generated through pin10/11 of IC4047 gets chopped and "carved" as per the applied PWMs.
The resulting output to the transformer also causes a pure sine wave to be stepped up at the mains AC secondary output of the transformer.
The formula for calculating R1, C1 is given in this article which also tells us about the pinout details of the IC 4047
For the NE555 stage C may be selected near 1uF and R as 1K.
Assumed output waveform
More info on how to use IC 555 for generating PWM
An RMS adjustment could be added to the above design by introducing a pot voltage divider network across pin5 and the triangle source input, as shown below, the design also includes buffer transistors for improving mosfet behavior
The above pure sine wave inverter design was successfully tested by Mr. Arun Dev, who is one of the avid readers of this blog and an intense electronic hobbyist. The following images sent by him prove his efforts for the same.
More Feedback
Inspiring response received from Mr. Arun regarding the above IC 4047 inverter results:
After completing this circuit, the result was amazing. I got full wattage by the 100 W bulb. Couldn't believe my eyes.
The only difference i had made in this design was replacing the 180 K in the second 555 with a 220 K pot to adjust the frequencies accurately.
This time the result was fruitful in all respects... On adjusting the pot, i could get a non disturbing non flickering full wattage glow in the bulb, also the 230/15 V transformer connected as the load gave a frequency in between 50 and 60 ( say 52 Hz ).
The pot was adjusted gently to get a high frequency ( say 2 Khz ) output from pin#3 of second ic 555. The CD4047 section better calibrated to get 52 Hz at the two output terminals....
Also I am facing a simple problem. I have used IRF3205 mosfets at the output stage. I forgot to connect the safety diodes across the drain terminals of each mosfets...
So when I had tried connecting an another load ( say table fan ) in parallel to the given load ( 100 W bulb ), the glow of the bulb also the speed of the fan was reduced a little and one of the MOSFET was blown due to the absence of the diode.
The above 4047 sine wave inverter circuit was also tried successfully by Mr. Daniel Adusie (biannz), who is a regular visitor of this blog, and a hardworking electronic enthusiast. Here are the images sent by him verifying the results:
Sawtooth Waveform Oscilloscope Output
Illuminating a 100 Watt Test Bulb
The following images show the modified waveforms at the output of the transformer as captured by Mr. Daniel Adusie after connecting a 0.22uF/400V capacitor and a suitable load.
The waveforms are somewhat trapezoidal and are far better than a square wave which clearly shows the impressive effects of the PWM processing created by the IC555 stages.
The waveforms could be probably even further smoothened by adding an inductor along with the capacitor.
Showing an near Sinewave Oscilloscope Trace after PWM Filtration
Interesting feedback received from Mr. Johnson Isaac who is one of the dedicated readers of this blog:
Good day
In your post, Pure Sine Wave Inverter using 4047, in the second I.c stage (ic.1) you used 100 ohms resistor in between pin 7 and 6.,
Is that correct? I use to think an astable multivibrator using 555 pin configuration should have the 100 ohms between pin 7 and 6. Also, the 180k variable between pin 8(+) and pin 7. Pls check the pin connection and correct me pls. Because it oscillate sometimes and it doesn't sometimes also. Thanks,
Isaac Johnson
Solving the Circuit Issue:
In my opinion, for a better response you can try connecting an additional 1k resistor across the 100 ohm outer end and pin6/2 of IC1
Johnson:
Thank you very much for your response. I actually constructed the inverter you gave in your blog and it worked.
Though I don't have an oscilloscope to observe the output waveform BUT I bet readers its a good one cos it operated a fluorescent tube lamp in which any modified or pwm inverter can't power on.
See the picture sir. But my challenge now is when I add load, the output flickers sometimes. But am happy its a sine wave.
Video Test Waveform
Simplifying the above Concept
The above explained IC 4047 pure sine wave inverter can be actually simplified greatly by eliminating two IC 555 configurations from the design.
The basic idea is to produce a synchronized sine PWM output for chopping the MOSFET switching so that this SPWM waveform is replicated at the output of the transformer and is transformed into a pure sine waveform. The complete circuit diagram can be seen in the following diagram:
In this simplified design, we yet again exploit the pin#13 square wave output from the IC 4047 and convert it into triangle waves. This triangle wave is then used to modulate the PWM output of a IC 555 astable to create the required synchronized SPWM for chopping the MOSFET gates.
The capacitors Cx and Cy will need to be experimented a bit to create a proper triangle waves from the RC network output.
Remember, you will need an oscilloscope to check and confirm the various waveform discussed in the above diagram.
Another Simpler Looking Options
The following concept discuses a rather simpler method of modifying an ordinary square wave inverter using IC 4047 into a sine wave inverter through PWM technology. The idea was requested by Mr. Philip
Technical Specifications
I hope that i am not going to be a bother, but I need some advice with a PWM-controlled modified sine wave inverter I am designing so I want to seek your expert opinion.
This simple design is tentative, I haven't implemented it yet but I would like you to take a look at it and tell me what you think.
Also I want you to help answer some questions which I have not been able to find answers to.
I have taken the liberty of attaching an image of a quasi-block diagram of my tentative design for your consideration.
Please help me out. In the diagram, the IC CD4047 in the inverter is responsible for generating square wave pulses at 50Hz which will be used to alternately switch on MOSFETS Q1 and Q2.
The PWM circuit will be based on IC NE555 and its output will be applied to the gate of Q3 so that Q3 will provide the PWM. Besides this, I have two questions.
First, can I use square waves for the PWM pulses? Second, what is the relationship between PWM frequency and supply frequency? What PWM frequency should I use for a 50Hz inverter output?
I hope that this design is feasible, I think it is feasible, but I want your expert opinion before I commit scarce resources to implement the design.
Looking forward to hearing from you sir!
Sincerely, Philip
Solving the Circuit Request
The configuration shown in the second figure above would work only if the center tap mosfet drain/source pins are swapped and N-channel mosfets are used for the 4047 inverter oscillator output, as shown below:
The PWM section should be built as I have explained in this article:
The PWM transforms the flat square waves into a modified square wave by chopping them into smaller calculated sections such that the overall RMS of the waveform becomes as close as possible to an actual sine counterpart, yet maintaining the peak level equal to the actual square wave input. The concept may be learned in details here:
However the above transformation does not help to eliminate the harmonics.
The PWM frequency will be always in the form of chopped square waves.
The PWM frequency is immaterial and may be of any high value, preferably in kHz.
How to Add Feedback Voltage Control to a 4047 IC Inverter
In this section we will discuss how to add an automatic feedback voltage control to a 4047 IC based inverter circuit.
If you don't want to read the whole explanation, you can watch the following video instead:
This type of feedback network is intended to ensure that the AC output voltage from the inverter never exceeds a predetermined safe value. For example, using this automatic feedback control, a 220 Volt inverter circuit output could be restricted to maximum 230V AC level, which may be safe for most 220 Volts appliances.
For a 120 Volt inverter system, this feedback network could be adjusted to restrict the output AC to a maximum of 115 Volts AC, which may be safe for most 110 Volt appliances.
How the Feedback Circuit Works
Now let's understand how the simple feedback network is designed to work, by referring to the following circuit diagram:
The mains AC voltage from the inverter transformer secondary is first converted to a DC voltage using a bridge rectifier.
This bridge rectifier is built using 4 numbers of 1N4148 diodes.
The DC 220 Volts output from the bridge rectifier is applied to an adjustable voltage divider network built using a 220 k resistor and a 100 k preset or trimpot.
The 100 k preset is carefully adjusted such that its central wiper terminal generates around 1.2 volts in response to an input AC voltage which is considered high, and needs to be restricted.
Let's say, the input AC needs to be restricted at around 270 Volts, then the 100 k preset may be adjusted so that its wiper terminal generates a proportional DC voltage level of 1.2 Volts.
We select a 1.2 Volt output because this is the equivalent DC level required to just switch ON the attached BJT device.
That means, whenever the inverter output AC voltage tries to exceed the 270 Volts mark, it causes the BJT to turn ON and become conductive.
When the BJT conducts, it starts grounding the CT pin of the IC 4047.
Since the RC network associated with the CT and the RT pinouts of the IC determines the output frequency and PWM, the grounding of the CT pin instantly causes the output PWM and frequency to nullify, which in turn causes the output AC voltage to dip.
When this happens, the feedback voltage to the BJT also drops proportionately until the BJT is turned off. In this situation the IC output PWM is restored back to its previous form, and if the output voltage continues to rise, it yet again activates the BJT via the feedback network, and this feedback on off cycle keeps repeating rapidly, ensuring that the output AC is not able to rise above the set threshold, which is 270 volts in our example.
This concludes our feedback control circuit explanation, now let's try to understand how this feedback circuit can be setup prior to integrating it with the inverter circuit.
How to Setup
The next diagram below shows the isolated feedback circuit, which can be set up by implementing the following steps, before interfacing it with your inverter circuit:
Initially keep the 100k preset's wiper arm fully towards the ground side of the DC supply.
Now, switch ON the 12 DC supply and then switch ON the AC supply to the bridge rectifier whose voltage level is around the desired high cut-off limit.
Next, slowly adjust the preset using a well insulated screw driver, until the LED just begins to illuminate.
To confirm the results, try varying the input AC voltage around the cut-off threshold and watch the LED turn on and off at the thresholds. Although the cut-off may not be too sharp, yet it will do the job of the intended output voltage control of the inverter quite well.
That's it! This simple procedure should be enough to complete the setting up of the feedback circuit.
After this, make sure to seal the preset adjustment with some super glue.
So, this concludes our explanation on a feedback circuit for the 4047 inverter.
Pseudo-sinusoidal IC 4047 Inverter Circuit
From a continuous source, battery, or vehicle alternator, it is possible to produce a 50 Hz voltage/pseudo-sinusoidal waveform, using this simple IC 4047 inverter circuit. The design is capable of operating many low-power devices that require a voltage of 220 V AC, typically supplied by the AC mains grid distribution network. The power of this module depends largely on the chosen transformer and, above all, on the continuous source's ability to supply the circuit without failure.
Working Principle of the circuit
Being able to power a device on the 220 V AC network when no mains AC power is available can be very convenient. We particularly think of campers, caravanners, fishermen, and motorists.
Although this simple setup does not provide a 100% clean sinusoidal wave, it can still satisfy many undemanding devices such as incandescent or fluorescent lighting, soldering irons, small motors, etc.
The power can reach up to 250 VA if the continuous source is strong enough and an adequate toroidal power transformer is chosen.
The power transistors are rated for 30 A, provided that a substantial heatsink is used.
We even suggest adding a small fan directly connected to the 220V output, which will prevent it from operating without a load.
Analysis of the Circuit Diagram
To obtain an alternating voltage from a DC source, the simplest solution is to use an inverted transformer: the low-voltage secondary winding has a center tap.
It is then sufficient to alternately supply power to the two windings to produce a symmetrical, but non-sinusoidal, variable voltage on the primary side if the low-voltage secondary winding is driven by a rectangular signal with steep edges.
Two complementary and opposite signals are required, and the CMOS integrated circuit with the reference 4047 is used to generate them, capable of either building an astable or monostable flip-flop.
The proposed diagram is shown in the figure below.
Of course, we will operate our circuit as an astable generator, ensuring a precise frequency of 50 Hz. This task is entrusted to components C1 and P1. Some pins of the IC1 circuit are connected to the ground or the positive supply, depending on our needs.
For more information, you will find an explanation in the appendix about the multiple possibilities of this practical little integrated circuit.
The symmetrical square voltages available at pins Q and Qdash (corresponding to terminals 10 and 11 of the circuit) are routed through resistors R1 and R2 to an adjustable element. Its role is to balance the amplitude of the two signals and facilitate the adjustment of the control module.
Note that the duty cycle will be exactly 50% by design. The sliders of elements P2 and P3 control the base of a 2N1711 transistor, which is responsible for driving the downstream power semiconductors.
Components R7, R9, C4, as well as R8, R16, and C5, form a coarse filter capable of smoothing out the signal angles to some extent.
This will allow us to create a "pseudo-sinusoidal" signal that will control the intermediate transistors T3 and T4 mounted on the small control board.
The BDX 77 models are rated for an emitter-collector voltage of 80V and a maximum peak current of 8A. They are delivered in a TO-220 package and will benefit from a heatsink.
The secondary windings of the transformer do have a common point connected to the positive pole of the power supply.
The other end of the coils will receive the ground through the power transistors T5 and T6, a model not much larger than the famous 2N3055 but with a maximum peak current of around 30A in this case.
It is the NPN bipolar model with the reference BUX 39.
Diodes D1 and D2 absorb the unavoidable breakdown current produced at each interruption of the inductive element, which is the transformer.
The primary of the transformer, a toroidal model in this case, delivers a 50 Hz AC voltage.
The component labeled Gemov (or varistor) is placed between the output pins to clamp excessive voltage surges that may occur.
Two wires can also be tapped from the output to operate a fan directly powered by 220V, which will provide airflow to cool the transistor-heatsink assembly.
It is important to ensure that the voltage of the continuous source does not drop too much or be completely depleted in the case of a lead-acid battery.
It goes without saying that the input DC current can reach considerable values if, for example, a power of 200VA is desired. It would be prudent to include a robust series fuse, similar to those found in a household installation.
Construction
The creation of two printed circuit boards is necessary: the first one, shown in the figure below, is designed for the components described in the control module.
The layout is not very dense, but it is still recommended to use pre-sensitized copper-clad boards for reproduction.
After etching and rinsing, various drillings are carried out. Care must be taken to carefully mount transistors T3 and T4 on a small heatsink, which is directly attached to the epoxy board.
From this board, six wires will go to the significantly larger power module, and the track layout at a 1:1 scale can be found in the figure below.
It should be noted that certain tracks on this simple IC 4047 inverter circuit board will carry high currents and require special treatment. We recommend soldering bare copper lengths, with a section of approximately 1.5 mm2, directly onto these tracks.
For example, electrician's copper wire with the insulation removed can be used. Care should also be taken to ensure all connections between the two boards, and in particular, to avoid reversing the wires.
The transformer has six wires, with the two thinnest wires corresponding to the primary, and therefore our 220V output.
It is important to properly identify the other windings before soldering them permanently. This assembly can be housed in a sturdy, adequately ventilated metal enclosure.
How to Setup
We leave it to you to complete this final step for this simple IC 4047 inverter circuit. After a thorough check, the frequency can be adjusted to 50 Hz under no-load conditions using the adjustable preset P1, if you have an oscilloscope or frequency meter.
Otherwise, simply set this element to the midpoint position. The other two adjustable components are set to obtain a symmetrical signal in amplitude.
Initial tests can be performed using a simple socket where different power lamps can be connected. For resistive or slightly inductive loads, there should be no serious issues.
Proceed with caution when testing devices that typically require a true sinusoidal voltage.
Dear sir,
Please sir, for a 600VA transformer, if the max output power of a transformer is 360W.
In a situation where a 12V, 30Ah battery for delivering 360W for one hour is not handy
Please sir,
1. Can I use a 12V, 25Ah battery to deliver 100W to run a load of 100W for 3 hours?
2. Can I use the IRF3205 mosfet in the pure sine wave inverter with RMS adjustment for the 12V, 25Ah battery to run the 100W load for 3 hours?
3. To calculate the inverter supply current in order to know the protection diode to use across S/D pins of the mosfet, please sir, will it be 100watt / 220V inverter supply voltage = 0.45A if am using the 12V, 25Ah battery?
Hello Godfrey,
1) you can 25 Ah battery for running a 60 watt load, not a 100 watt. You must discharge the battery at a maximum 15% of the Ah value
2) You can use IRF3205
3) protection diodes can be rated at 5 amps which is the recommended discharge rate of the battery, or the operating current for the inverter with a 25 Ah battery
Okay sir, thank you for your reply!
Please sir, to get you very well about the 15% max discharge.
1. Do you mean that, though the 12V, 25Ah can deliver a Max power of 100W for 3 hours, it must not be used to run a 100W load even for a very short time, say 5 minutes?
2. Please sir, in a general view, what is the recommended discharge rate or the max percentage discharge for a battery with respect to its Ah value?
3. Please sir, how do you calculate the 5 Amps discharge rate of the battery and the operating current of the inverter?
Godfrey, there are no fixed parameters in electronics, all parameters are relative and approximate values.
A lead acid battery must be charged or discharged at around 10 to 15% of its Ah rating to prevent cell deterioration. Therefore for a 25 Ah, the maximum discharge current should be around 4 amps, and not 5 amps.
So if yo multiply 4 amps with 12 V, gives 48 watts, so that’s the maximum load recommended for your inverter.
Now Ah = 25, and considering A = 4 amps
we have
h = 25 / A
h = 25 / 4 = 6 approximately, which is 6 hours back up time in ideal situation, practically it may be just 3 to 4 hours due to many hidden losses.
Okay sir, thank you very much
Dear sir,
Please sir,
1. From the theoretical 6 hours, what is the formula to calculate the actual time the battery should be discharged practically?
2. Please sir, If the current rating of my system is between 1.12A to 1.44A, can I use 1A diode like IN4007 for the avalanche protection?
3. Please sir, will increase in the resistance of the 10K preset from 5K upward increase the RMS output voltage of the inverter to the rated value or decrease it?
Hello Godfrey,
1) Please read the article Lead Acid Battery Charging
2) Yes, that will do
3) Moving the slider towards the capacitor positive will increase the RMS and moving it toward the ground will decrease the RMS
Dear sir, please sir can I use IRF3205 MOSFETS for the pure sine wave inverter circuit with RMS adjustment?
yes you can use it….
Thank you sir
Dear sir,
Please I have a 10A ups transformer having four wires(black, blue, green and yellow) on the primary side and two fat wires on the secondary side.
When I applied 220V across the black and blue wires, I got 14V from the secondary.
Please sir I want to know if I can disassemble and centre tap the secondary to be 7-0-7v , and then use it for the above pure sine wave inverter circuit you designed?
Hello Godfrey, you can do that, just pull out a center tap from the middle of the 14V winding….and then you can use it for making any center tap transformer based inverter
Dear sir, thank you for all your tutorials on pure sine wave inverter circuit. I really appreciate it.
I wished to have been done building, testing and confirming your great design and work on this inverter circuit diagram by this weekend, but just one part of the components is keeping me. I have searched through many electronic part shops in my area. I can’t find the a TRANSFORMER with the 10A current rating you recommended for me. The highest current rating seen in all the shops is 2A.
I saw 240/15-0-15v, 2A transformer (iron laminated):
1. Please sir can this transformer be disassembled and rewound based on specifications to output 9-0-9v, 10A you recommended for me to use for 60W inverter circuit?
2. I have also seen a UPS transformer during my search for 9-0-9v, 10A transformer.
The UPS transformer has four wires on the low voltage winding and two wires on the high voltage winding.
Please sir can the UPS transformer be useful for the inverter circuit in question?
3. I would really love to design and build my own inverter transformer, please sir I would appreciate my help on how to design and build the transformer and the materials I need to use.
Although I have read your post on “how to design your own inverter transformer”, I am not getting it well. Please sir throw my light.
Thank you for your time.
Hi Godfrey, yes you can rewind the transformer for higher current if the space between the core allow the accommodation for the winding.
2) transformers are all similar with their working principles, so UPS transformer will also work.
3) Transformer designing should be done only with the recommended formulas, so you will have to follow the mentioned formulas in the article, there’s no other easy method.
Alternatively, you can also refer to the following article for more info:
How Transformers Work
Thank you very much sir!
Please sir concerning the UPS transformer, the one I have has four small wires on one winding (i.e black, blue, green and yellow wires),
and two fat wires on the other winding(i.e blue and red wires).
I didn’t know which winding is primary and which is secondary.
So I downloaded two videos on YouTube about the transformer.
From the two videos, i learnt that the winding with four wires is taken to be the primary, and was supplied with 230v mains. The black wire from the four wires was the COMMON. So from the voltmeter that was connected across the two fat wires(as the secondary), when 230v was applied across black and blue, the voltmeter read 14v; black and green = 5v; black
and yellow = 7v.
1. Please sir my question is how can I use this transformer with the above pure sine wave inverter circuit you designed? How will I connect the transformer to the circuit?
Thank you sir.
Godfrey, the transformer ratings cannot by assumed by guessing, you must check it practically by feeding the 220V on the primary side and then checking the corresponding voltages on the secondary. If the voltage matches the specifications provided in the above sinewave inverter circuit only then you can use it, otherwise not.
Alright sir. Thanks very much sir for your time!
So there’s no 22k resistor in the circuit, please sir any need for protection diode for the MOSFET?
You are welcome Godfrey, yes there’s no 22k in the diagram, you can add external protection diodes across S/D pins of the MOSFETs for increased safety
Okay sir, thank you very much.
Let me go about with the design.
Dear sir,
1. Please sir can I mount the two IRF540 MOSFETs on one heat sink? Or if the two mosfets are not to be mounted on one heat sink, can I use heat sink insulator pad or use two heat sinks separately at once?
2. Please sir what protection diode can I connect across the S/D pins of the mosfets? And also which terminal of the diode (cathode/anode) is connected to the D pin and the S pin of the mosfets?
Thank you sir!
Hello Godfrey,
1) yes you can mount two MOSFETs on a common heatsink, preferably you can use heatsink insulator with them.
2) You can use a diode with current rating equal to the current rating of the inverter, cathode will go towards the positive supply line, and anode towards the negative supply line.
Okay sir, thank you sir!
But am confused somewhere: I don’t know how to get the current rating of an inverter. Please sir help me with the formula for calculating the current rating of an inverter.
Thank you
Please divide wattage of the inverter with its voltage
Dear sir, I would like to sieze this opportunity to thank you for your time and the great offer of help you have made tutoring electronic engineering lovers in circuit designs. I really appreciate it.
Please sir I would like to build the pure sine wave inverter circuit using IC 4047.
I want to go for your second circuit diagram which has RMS adjustment and buffer transistors for improving mosfet behavior.
Please sir I have some questions I want to get clarified about the circuit.
Q1. In your post on IC 4047 data, you said R1, P1 and C1 determine the oscillator frequency of the IC and the output at pin 10 11 and 13. Please sir, what value of R1 and C1 should be used and what resistance value should P1 be set to in order to get 50Hz source frequency from the inverter?
Because I haven’t seen the formula for calculating R1 and C1 in this article and also frequency meter is not handy with me for now.
Q2. Please sir what is wattage of the resistors used in the inverter circuit?
Q3. Please sir, the 10K preset, is it for RMS adjustment? Is the RMS adjustment responsible for output voltage of the transformer inverter? And also what resistance value should it be set to?
Q4. Please sir, the 10nF and 1uF capacitors, can I use ceramic or polyester type? Again, what is the voltage of the capacitors? Also what is the voltage of the capacitor C = 1uF at NE555 stage?
Q5. Please sir, do I need to work with these formulas in order to ensure good performance of the inverter?
f = 1/8.8RC at pin#10 and pin#11
f = 1/4.4RC at pin#13. of IC 4047
Pulse time, t = 2.48RC
Q6. Please sir, is the NE555 the same as IC (7)555 ?
Q7. Please sir, is there wattage of the 3v zener diode considered or any 3v zener diode is Ok?
Q8. Please sir, is the circuit diagram Ok or any modification needed?
Finally, what core type is used for the inverter transformer? Again, what is the minimum specifications for the center tap transformer and the battery to be used in order to get 100W output from the inverter.
Thanks very much sir for your anticipated effort and time to through all these questions. Looking forward to hearing from you.
Hello Godfrey, here are the answers for your questions:
1) You can use 56k for R1 and 0.1uF for the C for approximately 50 Hz output.
2) All resistors are 1/4 watt 5% and capacitors can be disc ceramic or PPC for the non polar, and electrolytic for polarized. 1uF can be a polarized capacitor.
3) yes RMS can be used for fixing a constant 220V/120V output
4) All capacitor voltages should be at least 2 times the supply voltage.
5) You can confirm the frequency with a frequency meter, calculating using formulas is not necessary.
6) NE555 is analogue, and 7555 is CMOS, both will work
7) 3V zener can be a 400 mW zener
8) Circuit is OK.
transformer core is iron laminate. specifications will be 6-0-6 /18 amps/ 220V for a 12V battery 100 watt
battery should be rated at minimum 25 Ah
Thank you very much sir for your great tutorial.
Please sir am not getting this point well
“All capacitor voltages should be at least 2 times the supply voltage.”
1. Please sir, is it with respect to the supply voltage of the entire inverter circuit (which I will use 12V lead acid battery) or is it with respect to the voltage across the individual capacitors?
2. Please sir can I use disc ceramic capacitors rated either 25v, 50v, 100v or what voltage, out of the three voltage ratings will be Ok? because I want to use 12v lead acid battery for the inverter circuit.
3. Please sir, another thing is, I may no longer want to go for 100W output power from the inverter since the transformer and battery specifications for the 100W power output seem unreachable for me for now.
However, my intention is to power 5pcs of 10W/220V/50Hz LED bulb lights for about 4 hours daily after full charge of the battery before in use. I also want to leave an extra power of about 10w in the inverter. So please sir, what specifications of transformer and battery will be fit to power the five 10W/220V/50Hz LED bulb lights and still retain 10w power in the inverter?
Thank you sir for your time!
Hello Godfrey,
the rule of thumb is to use capacitors having voltage rating two times the supply voltage from the power supply, in your case it should be 24V or higher.
This is true for all the capacitors.
The transformer for the mentioned inverter specifications can be a 9-0-9V 10 amps/220V and the battery can be rated at 12V 20 Ah
Thank you very much sir for the tutorial. I really appreciate your time and effort.
Glad to help!!
Dear sir, please I forget these points:
1. What is the MOSFET value for the second circuit with RMS adjustment?
2. What Is the value of the electrolytic capacitor C at NE555 stage of the circuit?
3. Please sir the value of the resistor between zener diode and the electrolytic capacitor on the left side of the circuit is not seen clearly. Please sir, is it 22K or 2.2K?
Thank you very sir!
Dear Godfrey, 1) The MOSFET power handling capacity will dependent on the power spec of the inverter. For moderate power you can use IRF540
2) you can use 10nF ceramic disc for the C.
3) It is 2.2k
Hello everyone! I need help! I made a simple inverter and when there is no load the voltage is 220V but when I plug in the load it becomes 30V. The load is 80W
Hello Swagatam ! What is the value of P1 between R1 and pin 3 of 4047 IC ? please tell me this only one you leave.
Hello Than, it is a 22k preset
Thank you so much! Swagatam
My pleasure!
Thank you so much sir swagatam, you have solved my problems.
You are welcome Evans!
sir can you look at this circuit
https://www.homemade-circuits.com/wp-content/uploads/2020/09/555-inverter.jpg
will it work or any kind of modification needed.
Shankar,
yes it will work….no modification needed
thank you sir for your valuable comments.
sir why are you inactive in youtube now?? any reasons
sir i dont understand the circuit in given website. can you explain me.
bcuz in your circuits the ic555 pwm are fed to the base of mosfets but in this circuit the pwm is directly fed to emitters of bc547 transistors.
thanks
Hi shankar, because I am too busy writing articles and answering to comments in my blog. The shown diagram is not a sine wave inverter, it’s just a RMS controlled PWM inverter.
Actually there’s a mistake in the diagram, the emitters are shown connected with the transformer, rather it should be the collectors that must connect with the transformer, and the gate resistor must be connected with the +12V battery rail.
It’s just another way of inducing the PWM chopping to the MOSFETs.
Please sir, the first design you made without the RMS adjustment and the second design that has RMS adjustment, which circuit is completely okay for implementation.
2. Which circuit is a sine wave inverter circuit?
Both the circuits are OK.
The second circuit is sine wave.
Okay, thank you very much sir.
Please sir, I don’t get this point u replied Shankar.
“…and the gate resistor must be connected with the +12V battery rail.”
Please sir which one is gate resistor in the second circuit?
Godfrey, the reply is not referred to the second diagram, rather to this diagram:
https://www.homemade-circuits.com/wp-content/uploads/2020/09/555-inverter.jpg
The circuit has some problems…the pin#3 PWM out of the IC 555 is connected with the collectors of the BJTs which will not do the intended job.
Hello sir swagatam,if I apply the values of C1 and R1 given in this https://www.homemade-circuits.com/wp-content/uploads/2013/06/IC4047invertercircuit.jpg to your above idea, can the circuit to give me an output with a 50HZ frequency? I have a challenge matching or calculating values for C1 and R1 in your diagram for 50HZ?
Hello Evans, it is very easy to set the 4047 output frequency to 50 Hz, by using a 100k preset for the resistors, and a 0.1uF for the capacitor and then verifying the adjustments through a frequency meter connected at the pin10 or pin11 and ground.
Please Sir,do you have a design for pure sine wave inverter Schematics using ferrite core transformer?
Hi, we have a related concept which you can find it in the following link:
https://www.homemade-circuits.com/5kva-ferrite-core-inverter-circuit/
Hi Swag,
Can i use dc4047 to generate pure sine wave of 15 to 25KHz using monostable option and mcu generated pwm to trigger the sc4047 trigger(+).
Thanks in advance
Hi Lee, that may be possible, but i am not sure about it.
Hi Swagatam Sir
If I don’t want to use more than 2 or maximum of 4 MOSFETs in my 500W inverter, what MOSFET can I use? And does it need protection diode across its drain and source?
Also, does it require a cooling fan after a heat sink or heat sink only is required?
Thanks Sir.
Hi Sodiq,
You can use 2 IRF540 MOSFETs on each channel, total 4. Yes protection diode is recommended. You can put 1 diode each across center tap and the outer taps of the transformer. If the heatsink are large enough then cooling fan may not be required.
Hi sir swagatam,I would like to request if possible you design or provide for me a circuitry for battery monitoring in inverters such that when the battery voltage goes to about 10.5v,the circuit be able to have an indicator to show low voltage accompanied with a buzer to give a sound warning. And at the same instance the circuit be able to have a low battery cutoff so that when the battery goes below 10.5v ,the SCR connected to the inverter driver supply is triggered hence shutting down the inverter until the battery is charged properly to the required voltage,this will help protect the battery banks from be drained to zero hence destroying the battery. If possible sir, let this circuit operation be able to be adjusted manually with the help of some preset pots. I am designing a circuit drive for a 24v inverter using CD4047, the diagram is the second one in this article. Also if possible help with charge control circuit for 24v inverter charger with float charging, thanks.
Hi Evans, you can easily modify the following circuit designs for the specified operations:
https://www.homemade-circuits.com/how-to-make-simple-low-battery-voltage/
https://www.homemade-circuits.com/low-battery-indicator-circuit-using-two/
https://www.homemade-circuits.com/low-battery-cut-off-and-overload/
Sir, can the second circuit run a 65w fluorescent light and a 2200w refrigerator if all the parameters are calculated carefully? Let me also know if this circuit can work on a h bridge system,what will be the design?
Yes it will work. For an H bridge design you will have to use specialized ICs.
Thanks for your response sir,I’ll try it out and come back here in case of any clarifications.
Thanks for your response sir, only but to ask will the specialized ics be integrated to this circuit or will be a circuit on its own? Remember I have a two wire transformer how will I connect it to the above circuit? Waiting urgently for your response.
For 4 N channel full brdige you will have to use specialized IC as suggested in one of my earlier comments. 4047 cannot be used
Understood sir,thank you so much for your efforts.
You are welcome Evans!
Sir the IC you in provided link is not available in my country (Kenya) any equivalent please? Or any help with h bridge?
Hello sir swagatam, please help me solve the following
1. How can I improve the second circuit to a spwm using opamp? Help with a circuit diagram
2. If I trafered this oscillator to a full bridge system that has a boostraping network,will it work? Will the buffer stage be of importance or what changes needed.
3. What is the size of the IN4148 (quarter/half)
4. If I use bc557 ,at the buffer stage how will be the connection.
5. “The configuration shown in the second figure would work but only if the centre tap pwm mosfet is replaced with a p-channel mosfet” sir am unable to understand this statement.
Hello Evans,
1) I have already explained the process in the SG3525 article, the process will be the same.
2) I have already suggested you that 4047 can be used with a discretely built full bridge, buffer stage will not be required
3) Please refer to the datasheet of the 1N4148 diode to get the details.
4) yes use a p channel with correct pinout orientation, the diagram shows a wrong orientation, which was referred from some other source.
Ok sir swagatam. From the circuit using ic 4047 with pwm using ic ne555 that you recommended, help me identify the fast and low frequencies to feed to the opamp. Again do we feed to the lower side mosfets of the full bridge as was for the irs2453? If I connect this circuit that has pwm using 3 ne555 to the full bridge without disconnecting the buffer stage,is there any problem? By the way sir is spwm better than pwm? Just to only but ask.
Hi Evans, without an oscilloscope it can be impossible to know whether the circuit is really creating the SPWMs or not. The slow and fast triangle waves will also need to be verified using an oscilloscope. When PWM are appropriately dimensioned to create a sinewave it becomes sine pwm or SPWM
So you must have an oscilloscope to test these outputs
Thank you very much sir swagatam,I think I have now gotten help. Please sir what is the value of C in the first ic ne555 near the 10k pot itfrom the 2nd circuit with buffer stage? Sir is it wrong to introduce buffer stage in h bridge system?
Evans, the C value is given in the article. It is not wrong to include buffer stage in full bridge, but it is not required.
Sir Please help me with a schematic of the wiring of CD 4047 with pwm if I have a two wire transformer (non centre tap transformer)18-0-18, 90A how will the connection look like?, what changes are their when for example am using only N channel mosfets? Am using 200AH/12×2, With the help of a diagram,I’ll appreciate.
Hey swag, is it possible to make a pure sine wave inverter using cd4047 and resistors and capacitors filter circuit at pin 10 and 11 to filter out only sine waves to drive the transistors?
Hi Sam, no that’s not possible, unless you use the MOSFETs as source followers, which might waste a lot of energy. SPWM is the best and the most efficient way of implementing the same…
Sir.. Good day sir… I love your efforts in educating new learners in electronics.. Sir I need your help… Am having the materials.. But I am having problems I don’t have osciloscope and measuring device.. Only multimeter.. I just need a correct diagram and the fixed value of the variable resistors C1, P1, R1 of the 4047 and the 10k preset for 50HZ 220v… God bless you sir. Am a lady inspiring to become an electronics engineer
Hello Amblessed, you can try the second diagram, which is the perfect one. Use 56K for R1+P1, and 0.1uF for the C1. The 10K cannot be fixed and will need to be adjusted manually.
Hey Amblessed, use the formula in calculating for the resistor or capacitor value. 1/8.8*R*C, for example i used 1uf capacitor which is solving for the resistor value we have: 1/8.8*50hz*0.000001=0.00044=1/0.00044=2,272.73 ohms resistor for 50hz frequency. Hope this helps.
Thanks alot for everything swagtam, i love your page. Welldone for your replies.
You are most welcome Sam!!
Should i add a resistor to the collector or emitter of 2n2222 to reduce the current entring the 2n3055? What other transistor can i use apart from 2n3055, i want a straight case not a round one similar to the TO-220 case, but can be as large as IRFP150N packaging, but with high collector current say 50A to 100A. I’ll be glad if u can help me, thanks for everything so far.
No need of adding any resistor anywhere in the Darlington, connect it as a Darlington is supposed to be connected.
Even powerful mosfets can burn with a weak static electricity having microamperes, so its rating is not relevant to its burning issue.
The concept which I had referred in the previous comment is reliable and can prevent MOSFET burning.
you can use TIP2955 instead of 2N3055
Why TIP2955 [PNP] and not TIP3055 [NPN] ?
Yes, it should be TIP3055, not TIP2955
Is it better if i replace the 2n2222 for forming a darlingthon pair with tip122? Therefore using tip122 in place of 2n2222 to form a darlingthon pair with tip3055.
Yes, you can try that, that may give better current gain and better efficiency.
Will the mosfets stop getting burnt if i add the buffer stage? Because i like the inverter and i want it to work and stop stressing me. I tested it again today with diffrent mosfets it was fine just before the msft got burnt again. 2N3055 Transistor and SW50N06 msft which will work better please? Thanks in advance.
It shouldn’t but with MOSFeTs we can’t guarantee until everything is 100% favorable. If you use BJTs like 2N3055, there would no chance of burning unless you did something terribly wrong, but MOSFETs can burn even if you did everything correct, may be due to a loose connection, a stray inductance, sudden spike etc. However 2N3055 would generate more heat than a mosfet and waste precious power.
you can try the following configuration, I have more confidence in this BJT buffer:
https://www.homemade-circuits.com/1500-watt-pwm-sinewave-inverter-circuit/
If i use 2N3055 i should connect a 2N2222 with it to form a darlington pair, right? But the (Ic) of 2n2222 is only 0.15A and my battery is 7.2A/12V, how should i go about it? Or what other connection should i use? Thanks for the previous reply.
You can use 2N2222, it is only for increasing the gain of 2N2055, the actual current is handled by 2N3055, so it’s fine to use it.
Hi swagtam, i completed the circuit and tested it with a 12v 1a adapter and a 7.5-0-7.5/10a transformer it worked but the power was not enough, how do i solve that? Then i bought a 12v/7.2a lead acid battery and used a 15-0-15/2a transformer it also worked giving a voltage of 188-198vac then i tested it again with the 7.5-0-7.5/10a transformer, but the mosfets (IRFP150N, one for each channel) got burnt one by one. What is the cause, are the mosfets not enough.
Hi Sam,
did you try the second circuit? Because MOSFETs are very sensitive and a buffer stage is strictly recommended.
By the way the 7.5V 10A is the right transformer for this application, the 15V won’t be appropriate
Thanks a lot swagtam. Can i replace those 2.7v zener diodes with diode 1N4148? What are their uses in the circuit?
Hi Sam, 1N4148 will not do, you can replace it with a 4.7V zener or a 3 zener
So what transformer voltage and current can output 200w. Can the transformer be a step down transformer, used in power supply? And also please just like the reply to a questions above, about adding a 1k resistor across 100r in pin 7 of ic1 and pin 6&2 in the same ic, should i add that to avoid similar problem stated in the post above? If yes, should the same thing be done in ic2? And can all three ic’s be NE555?
You will need 12V x 20 amp = 240 watt transformer.
The 1K recommendation is only for IC1. not for IC2
Please swagatham, can i use transistor 2n3055 in place of the mosfet. Will sw50n06 mosfet work also? Thanks in advance.
Hi Sammy, yes you can, but add a 2n2222 with the 2N3055 to create a Darington pairs, and replace the 100 ohm resistors with 1 K 1/4 watt
And please, what symbol is that connecting from the positive rail to gnd through 470 ohms resistor in between ic 1 and ic 2, is it a 2.7v zener diode? Can i use ne555 for all three ic’s below the cd4047? And will the circuit output 200w with just 2 sw50n06 mosfets, 7.5-0-7.5 10a transformer and 12v 10a battery? If not please what are the requirements for 200-300w output power? Thanks for ur previous reply, well done.
Yes that’s a zener diode. MOSFETs are rated to handle over 2kva. transformer will not produce more than 100 watts
Please swagtam, i bought mosfet IRFP150N For the inverter, will it work for the inverter? And will a 15V-0-15V 2A Transformer be too much for a 12V battery, Or enough?
MOSFET is OK, but 12V will not work 15V, the transformer must be 9-0-9V
How to convert AC Square wave to AC sine wave(Transformer output)
What is the voltage level? if it’s 12V to 220V then you can use the concept which has been discussed above!
Can i use 3v to change 2v7? cause hard to find 2v7 in mycity
yes that’s fine…no problems
Hello Sir,
in reference to https://www.homemade-circuits.com/arduino-pure-sine-wave-inverter-circuit/, i tried designing my own using GFP50N06 mosfets from a junk UPS and its working though with issues i would like you to help me fix.
1. one MOSFET is overheating.
2. The transformer has a vibration sound
Since am an arduino fan am looking at adding more safety features to the design
Hello Cracker, in the recommended design, the two channels are perfectly balanced so one mosfet heating up is strange and should not happen. Also, since the design is an Arduino based the two channels has to be perfectly identical.
Make sure to switch ON the transformer center tap a few seconds after the Arduino has booted. This will ensure that the mosfets do not get direct voltage and they don’t get damaged.
Sir can the circuit work on 5 to 6v like that of arduino construction?
Saint, yes in the second diagram the ICs could be operated with 5V or 6V, but the power mosfet and transformer stage must be operated with at least 12v 3 amp or 5 amp supply otherwise you won’t be able to see anything useful at the output.
i understood now
Thank you sir
You are welcome!
GOODE AFTERNOON sir.
Sir is it possible to get a pure sinewave without the second part (555) part since the CD4047 Part has a chopping???
because according to your previous articles you mention that we can convert square sine wave to pure sine wave by using a chopping method
Engr Bashir, with only chopping you can optimize the RMS and get a modified kind of output but not a proper sine wave. For sinewave you will have to use a SPWM, therefore you cannot eliminate anything in the above 4047 designs.
OK sir. we are waiting for the updated one
Sorry, I forgot that it is already synchronized, pin13 of IC 4047 is connected with pin#2 of IC555
GOOD MORNING SIR i want to build this circuit today. please which circuit should i build the first one or the second one or the third one ???? because i want use more mosfet in parallel
Good morning Engr Bashir, Please build the second circuit which is technically more well designed.
The triangle waves coming from the left most IC 555 should be synchronized 50 Hz with IC 4047. I’ll try to provide an updated design soon.
Can I use a 12-0-12v 5a transformer along with 12v7ah battery?What will b3 the max output power?
If the battery is 12V, the transformer must be 7-0-7 or 9-0-9….12v transformer will result in a lower output AC
Sir,what will be the output power if 9-0-9V 2amp transformer is used?
Abhinand, if you multiply the voltage with current you will be able to get the wattage roughly. In your case it will be around 18 watts
Hi, my name is Fred, I love circuits but I haven’t had a chance to study about them, I like this circuit and would wish to build it coz av heard pure sine wave inverters are the best, would you plz list me all the components required so that I can try it, thanks
Hi, Please check the second diagram you will be able to find all the parts in the diagram, all the resistors are 1/4 watt rated, if you have specific questions you may ask them here
okay thanks, I’ll be trying to build it
Wonderful circuits.
How can I make the above circuit fit for a 3KVa inverter.
Urgent answer is required.
Thanks
Thank you, you can upgrade it to 3kva by modifying the mosfet rating accordingly, and by using a transformer and battery preferably rated at 48V… or 24V minimum.
Thanks I appreciate your urgent reply.
I will like to know the calculations involve in selecting mosfets and its number as well as for the batteries along with the suitable transformer ratings calculations.
Am having a 12V 100AH battery.
I awaits your response sir.
Please refer to the following post, it will explain you everything regarding the required calculations
https://www.homemade-circuits.com/how-to-calculate-and-match-inverter/
Sir I have build this circuit
correctly. I get 220v shortly.
All preset set mid.But i turn
left ic 555 around pin 7/6
1ok preset, 1fet (z44) get D/S
gate open shortly.
My circuit costume about 0.5A(no
include 1 pair of fet).
Around right ic 555 get very hot
and 100 ohm from pin7 become
hot.In that state I stop power supply.
I have not oscilloscope.
I keep trying for this project.
I build second picture of circuit.
I am waiting your advice.
mintheinkyaw, Please connect diodes across the drain/source of each mosfet, initially you can try 1N4007 if it helps to resolve the issue then later on you can replace it with 1N5408. make sure that the PWM frequency is not more than 300Hz, this can be set by adjusting R1 and C1.
Sir, I have successfully build the above circuit, I used irf3205 8psc and used 15-0-15 transformer, but when I increase the load from 200wt to 250 the output voltage reduce from 220v to someware around 150v and the brightness of my load reduced drastically.
Pls how should I iliminate this problem?
Congrats on that Kabir, can you please tell me the voltage and current specifications of your battery, and the current specification of the transformer….I’ll try to analyze the issue.
The battery voltage is 12.6v lithium battery and the current is 86amp. The transformer is rated 1000watt. It’s selvaged from computer u. P.s rated at 15-0-15/ 1000watt.
Kabir, if you use 12V for 15V transformer then the output will drop significantly. You will need a 9-0-9V 10 amp transformer if the battery is 12V rated. or if the transformer 15-0-15, then the battery must be rated at 18V or 20V
Thank you sir,
But the result of my inverter is highly appreciated. No noise and I can alter the output voltage the way I like it, the above inverter is really pure, thank you in advance.
That’s great Kabir, I am glad you are satisfied with the project…keep up the good work
sir pls what the data sheet of irf3205 or amperage
youngking, it is as follows:
VDSS = 55V (drain to source max voltage)
RDS(on) = 0.008Ω (drain to source resistance when triggered)
ID = 110A (drain to source max current)
Sir, what is the current rating of the transformer used in this circuit?
Transformer can be as per the user’s preference. It just needs to be matched with the battery AH, load, and the mosfet or vice versa..
Sir i hv a question , in ur above circuit can i use NE555 for all 3 IC’s , i mean can i use NE555 instance of ic1-(7)555 and ic2-(7)555 ? please make me that clear
Thank u.
Big problem is i am unable to find (7)555 ic in Bangladesh, Sir now what can i do?
any ordinary IC 555 will work, 7(555) is not compulsory…..
yes NE5555 will also work, any IC 555 will work
ok, if I use three NE555 for all those ic, is it need any change the connection?
No change will be required.
:yes NE5555 will also work, any IC 555 will work:
NE5555 or NE555?
any 555 will work, all are one and the same.
NE5555 is a 14 pin voltage regulator, please use your thinking also to understand the simple things.
sorry Mehedi, I misunderstood you, I might have added the extra 5 by mistake in my previous comment….
I hope you have used Darlington transistor at pin#5 of IC2?? using two BC547
do the following:
1) check the frequency at pin#3 of IC1 555 and make sure it is reaching IC2 555 pin#2
2) initially keep the emitter of BC547 disconnected with pin#5 of IC2 555 and apply an external varying 0 to 12V supply at pin#5 directly, check the pin#3 of IC2 555 for a varying PWM in response to this…you can check this by attaching a 12V flashlight bulb across pin#3/ground of IC2 555. make sure to connect the negative of the 0–12V with the negative of this circuit while checking
If the bulb light varies in response to the varying voltage then your IC1/IC2 are working OK.
now connect back the emitter to the pin#5 and check the response again from the triangle wave generator IC 555by varying the 10k preset.
OK!
it seem your IC1/IC2 555 stages are seriously wrong, either due to connection error or due to faulty parts, I cannot troubleshoot the fault from here, not possible…I would suggest that you first build the following PWM control circuit and get your IC1/IC2 555 stage correctly built. check whether the motor is changing speed in response to the pot adjustments…it should, I have tested the design thoroughly
https://www.homemade-circuits.com/pwm-air-blower-controller-circuit-for/
use Darlington for the BC547 stgae
pin#5 will not get damaged with external voltage because it has 1K resistor internally
yes all are 1/4 watt 5% CFR..this is always true whenever specifications are not provided
I hold Sukam inverter Sinewave Model Sturdy. I noticed the mosfets are burnt and i replaced the burnt mosfets. Before that i have removed the Inverter transformet connections and finally noticed when i give the 12volts battery connection the mosfets burnt. I am unable to understand where is the issue. Can you help me in getting for any idea what could be the faulty?
Please check whether the gates of the mosfets are getting the required oscillations or not from the oscillator stage…because if the mosfets do not oscillate then the mosfets will keep burning….
What type of sukam inverter ?i have some sukam circuit diagram but first check the IR2110 I belived its bad ..thats why it keep flashing your mosfet or the pic16f72 doesnt oscilate..
what about the LED? how is it responding….first build and confirm the LED circuit
https://www.homemade-circuits.com/low-battery-indicator-circuit-using-two/
Sir ….
I found some parts of value.
But i have not test.
I fix some parts of value in picture.
I sent some pic.
pls chack it and fix me sir.
Because of oscilloscope,
I have not.
But i will build circuit and test
Table fan/ Old black-white TV.
I collect some parts.
Thank… sir..
https://drive.google.com/folderview?id=0B33aafa8W22UTEZWQ281c0tzbmM
Aye,
It looks OK to me but I am sure about the frequencies, you will have to confirm and set it practically…
Thank for reply sir…
I use second pic and draw my book.
I want to know some parts.
In Ic 4047 ,
R1,P1,C1 their value in picture not show.
IN first IC555,
Resistor of BC 547 emittor show R
and condenser collector show C
can’t see their value sir.
IN second IC 555
Value of resistor can be 180k or 220K?
I little to ask.
All zena diode 2.7v can be replace
5.6v(1N4734).
2.7ZD can not buy in my country.
I am crezy hoby in electronic.
But i have not teach much.
I live in myanmar country (Yangon).
Thank alot for your teaching and project.
Hi Aye,
for the IC 4047 R1/P1/C1 you will have to check the datasheet of the IC or any other 4047 50Hz inverter disgram online you will find many diagrams, from where yu can copy the values.
That is not not BC547, that is BC557, please refer to the first diagram, the 555 section is clear in the first diagram you can copy the parts from there.
you can use a 220K preset and adjust the output accordingly, however 180K will OK…
zener diodes can be 4.7V or 3.3V
Let me know if you have any more questions.
Sir..
I need to build for
my home use…
Which one can be
use pure sine wave.
I see 3 circuits diagram.
They are not same.
pls…
Aye, you can the try the second one, as shown below:
https://www.homemade-circuits.com/wp-content/uploads/2013/10/4047rmsadjust-1.png
i have connected the circuit for pure sine wave inverter and the challange is if i try to connect load its damages the transistors,i have use two IRFZ44 transistors….what would be the problem or the cause?
connect reverse diodes across the drain/source of the mosfets and check the response, and also check the current consumption by connecting an ammeter in series with the battery positive, make sure this is not exceeding the mosfet max specification.
You will have to set the frequency by adjusting P1 and by measuring it practically at the output pin of the IC with a meter, I cannot say the exact part values. Frequency measuring facility should be there in your DMM, if not then buy one.
first make the circuit using a single mosfet, if everything goes well then you can go for additional parallel mosfets.
each mosfet should have its own gate resistor, the resistor ends must be shorted and joined with the BC547/BC557 emitter junction.
I hope now you have understood.
I cannot suggest about pin#9 PWM integration circuit because I am not sure about its results.
I would recommend the second circuit, and this circuit will also allow you to add extra mosfets in parallel.
Hello sir,had built the 3rd circuit. The one with pin #9 pwm integration,it oscillates but the problem is,whenever I connect it to the mosfets ,the mosfets blow boom into ????,I don’t know what could be the problem. Any help will be appreciated.
I have used a 20-0-20 transformer 1900w 80A. Would you please give me the values of the diodes that connect the gates to the pin #3 of ic2?
Irf064 is the mosfet am using?
Sorry I forgot to tell the voltage am using,am using 24v. More interesting is that if I connect to a 12v supply,the inverter operates and gives an out put of 125v but when I increase the voltage to 24,mosfets blows in about a minute,help know the problem.
Did you use 7812 IC for supplying 12V to the IC 4047? The IC will burn at above 15 V
The MOSFET is OK.
The diodes are 1N4148 and it is not related to the wattage of the inverter.
Evans, yes it is not recommended for newcomers, because the circuit requires many stagewise testings using an oscilloscope before getting the final results.
OK fine, if a non-polar cap is giving better results you can continue with it….