diy solar

diy solar

New no battery pure sine wave solar power system with smart switchers.

Thanks for ALL your work,
-will more 85 mfd 450v improve work ,ie motor start
-do you plan to use ISO on outside
Yes 85 MFD is the minimum, I will leave to the user to manage capacitor size for motor starts Warning capacitor charge/discharge warnings must apply ⚠️
One Meg ohm resistors will bleed down capacitors over time.

Just missing two 15Amp diodes to build one as soon as the new circuit boards arrive,
ISO transformer working just OK but additional improvements are needed to increase through put, it ran the small heater off the ISO transformer just fine.

Thank you for the starting information, still feel with improvement in the opto couplers drivers running the ISO transformers will be less of an issue in the future.

Right now a car battery could run the 555 60Hz signal for a month or more, 14 standard 12VDC solar panels will give you nice day time energy, charge battery systems for night time power and more 💚
Epoxy dip a working circuit board minus the heat sinks for ultimate weather proofing and out door durability.

More soon
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Link to get new two FET inverter circuit board build files Gerber/Drill files in a zip file format.

Three dots file for download.

Two new FET working parts list May 8th 2024 Grid Works.

1 P channel Mosfet IXTK40P50P
1 N channel Mosfet 40N65
2 12 Volt zener diodes 5Watt
1 555 timer
2 15Amp diodes or 4 10Amp diodes
2 Flyback diodes 10 amp 200 volt rated
3 1Amp diodes
1 5.7K resistor
2 15K : New data says 40K gate close resistor for N channel 30K for P channel
3 50K good qulity potenteometers
2 2A154k small green ceramic capacitors
2 optic couplers led input with Darrlington C/E output
3 820 ohm resistors
1 12VDC power supply must be isolated from earth ground/grid power
1 Inverter case with fan or heat sinks with fan
Each 140-160 VDC solar array needs 5Amp glass fast blow fuse and holder.
2 12K 5Watt resistors, Parts changes less heat and better stability
2 10MFD 200volt capacitors
1 225J630 filter capacitor
1 60hz 2,000 watt choke
2 85 Mfd capacitors 450Volt
2 800ohm resistors
2 10-15 amp glass fast blow fuse and holders for Inverter output 120 VAC 60Hz.

More soon 😀


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Big steps forward in both projects,Have been updating (any pictures with a zero or one view count are likely new).

Have everything I need to build one of new circuit boards and test upon arrival.

More soon 😀

Best wishes
Assembly tip use a large soldering iron to install pure copper wires to the circuitboard. Also use big iron to quickly solder in the big FETs and diodes. Put a small gap between the circuit board and the package of the 15Amp diodes when soldering in place think thermal and electrical isolation.

Use smaller iron with 555timer and the smaller parts.

Use isolation pads on the FETs, first test use dual 9VDC inputs and 12VDC on the 555timer circuit with a meter and oscilloscope you should be able to confirm basic operation and make safe changes if necessary.

Once you pass dual 21VDC input or higher the unit will likely run smooth at 140VDC solar inputs, Fuse everything with glass fuses.

I will make an instruction sheet after the first new circuit board build and testing.

More soon 😀
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Don't fall for this solar scam, sales person tells customer to sign IPad so they can run their credit score.

After refusing the solar installation because of the $70,000.00 cost people with no solar panels on the roof years later find they are in collection and a lean has been filed on the home owners house. One lady discovered all this two years later when she went to sell the home and could not.

The company still claims with a lobby full of protesters that these customers are just suffering buyers remorse.

I can not believe the number of scams that occur every day against American consumers.

Just want you to know that solar inverters and panels simply do not cost that much. $70,000 is a whole lot of electricity and most still get an electric bill that is now 29% higher than just 4 years ago.

More soon
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Real world report, at 5:00 PM yesterday the project system faulted and the lights went off.

The reason for the fault is simple attempting to run the mini split and more in the late afternoon after completely loosing sun conditions.In thirty minutes the system would have switched to grid power for the night. Going to re adjust the voltage controlled relays for better protection against this loss of solar.

Suspect one or more Mosfets have shorted source to drain and need replacing, Picture is of blown 10amp glass fuse from secondary ISO DC output from the diode bridge. This is the reason I say glass fuse everything.

More soon

Short has dissappeared on main project inverter, Total carnage 2 40N65 MOSFETs shorted source to drain, one 10amp fuse in the secondary ISO transformer, restoration in progress.


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Main project inverter restored, now just have to put it back on the shelf.

About 3 hours so far working on it, more soon right here.

All in all a easy repair, needs a couple small adjustments on the voltage controlled relays and ready for summer ☀️

This is one of the latest Kit inverter boards that I spaced the FETs wide for better heat distribution and shortest route for main power flow, Newest 40N65 MOSFETs have a 650Volt rating, old parts were 450Volt rated.✨

Voltage controlled relay #1 is now set for 100 VAC off/grid dump all extra loads (98VAC old setting) and 115VAC resets/restarts extra loads with delays. (Genius)

Project system fully functional again,💚


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Discovered a way to find shorted FETs with an analog ohm meter x1 scale without removing from the board, Found two in a row the bad components will show closer to zero than a good one.

Short will disappear the moment you remove the last bad FET. Replace the ones you cut out and presto new inverter again.✨

This tip can save you hours of labor fixing inverters, simple test between source and drain and only cut out the FETs that are closest to full short.

Project system running good but it is a passing clouds day, ⛅

More soon

Still have two of the premium P FETs new in the bag and the better 40N65s on the way, Expect to set new record high for watts with the two FET inverter, Have been working on the circuit board for the two FET inverter for days now free to anyone who wants it, Big improvement in trace isolation less possible to cross talk, Going to test the first one before releasing the new file to github.

Circuit boards due in the 23rd, 8 better quality 40N65 MOSFETs 650Volt 80amps on the way.

Seriously the two FET inverter system only requires 15Amps 140VDC, these parts should last forever in power production.😎
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Result from 2nd audit says two FET inverter needs dual output glass fast blow fuses 10-15 Amps because either FET can fail closed and cause a problem!

Parts list is being updated.

Enjoying full operation again on the Main project system comfortable on a 90 degree Fahrenheit day, voltage controlled relay #1 back to 98VAC for shed extra loads 😀
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Here is what works project system with three sets of 9 12VDC solar panels series 180VDC, 5amps + 5amps + 5 amps= 15Amps to run 120VAC mini split and more, Four FETs power board 40N65 and 15Amp ISO transformer output transformer, system allows you to add a secondary ISO transformer for 24/7 550+ watts backup secondary power and additional stability/ higher voltage for solar input.

The new two FET inverter is in beta testing 550 watts continuous output, 650 watts is currently the maximum I have seen to date. 700 watts and the FETs failed shorted source to drain, output good sine wave 120VAC 60Hz. Useful power.
Two strings of 7 standard 12VDC solar panels 140VDC, not tested yet parallel in additional groups of seven panels for more watts/amps power.😀

Can not wait to build the new circuit boards. More soon


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Running a Hybrid solar/grid home, water heater, dishwasher and night time usage on everything is grid, Looking for a $40 electric bill even with a 29% increase in the past four years the end result is good.💚

Right now on the project system running mini-split summer/ Quartz tube heaters in winter for comfort, running house lights and fans circuit,3 security cameras, two computer monitors, two stick computers and a mini-fridge.
Mini-fridge and electric bug zapper are on a dedicated two wire system (No ISO transformer test more than one year) also runs several modern battery rechargers for green lawn equipment.💚

Second much older solar/grid system runs full size side by side fridge (commanded by 15Amp smart switcher in the kitchen) Runs all living room electronics and clothes washer.💚
First Picture, most of my neighbors get a two or $300 electric bill.

Clothes drying is clothes line or grid powered dryer.

Old systems has 3 to 4 hours battery backup before I have to break out the gas powered inverter generator. Old system can run the new system but I currently keep the systems separated for cleaner test results and to simplify operation.

More soon 😀


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Guess what I am working on? 😀

New two FET kit inverter, hope to be testing by tomorrow noon.

Sent me 11 boards ordered 10, some of the hole could be one size larger, having fun with this first build.😊

30watt soldering iron seems to be working OK for assembly.
Best wishes


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Getting close, Four more capacitors , two optic couplers,1 resistor.

This is the 1,000 watt LC pure sine choke the 2,000 watt is a bit bigger.

New 40N65 MOSFETs are here 650Volt rating and 80amps, This build will be mostly new parts and Bench tested components, several first time events will occur tomorrow, solar panel testing will come later, tomorrow is about basic functionality and best sinewave output possible.

Already bench testing diodes and othe critical connections. So far so good.😀


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Big capacitors installed, Had to re learn optic couplers, pins straightened out for LED input and will be soldered directly to the board, will bridge in the C/E output with soldered in with small jumper wires. Only 4 connections to a 6pin chip,

Taking a break, finishing in the morning and directly to first inverter test dual 9VDC and 12VDC for the 555 timer. Will be looking for sine wave and output voltage from the FETs.

See several improvements that will improve the circuit board build, FET drill holes and conductors drill holes need to be larger, large cap drill holes need better spacing, version 1.2 in the works

More soon 😀
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Was up till 3AM last night working the cad program larger drill holes for FETs, input/output wires and large capacitors.
You will want a copy of the gerber/Drill files when I get it right.

Up since 8AM finished installing parts on the two FET inverter circuit board, 555 timer ran first time although the quality of square wave and cycle drift are not good enough yet.

Unfortunately the first dual 9VDC input test is a fail no output from either FET, Don't worry I will figure it out, Just takes step by step testing.

More soon, taking a break right now.


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Moving slow this morning, located the problem area closing optic couplers output does not trigger the FET gate on N or P channels, going to decouple the output of the optic couplers an see if I can get my 60Hz signal to the optic couplers output.

P channel has a 60Hz output to optic coupler output, no wiring changes yet but coming, not sure the floating 12VDC power supplies are working, slow step by step testing needed to fix issues.

Now have adjustable 60Hz signal on both optic coupler outputs N channel (Opto 1) needed the input reversed on the chip LED input, reversed the direction of the chip and resoldered in place. Pin one is positive and pin 2 is negative for the LED.

Baby steps till I get it right, all corrections will be forwarded to the version 1.2 circuit board and circuit drawings.

Can manually open the FETs main output looks nice, both gate close resistors working, Main error in 12VDC to power FET gates.

More soon 😀
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Something strange going on with the 555timer not getting the rock solid square wave I am use to and cycle drift is around 4 Hz instead of 1.5 HZ. Working on it.

P channel is working during latest testing and current timer configuration P FET gave me a steady 122HZ of full power 😍
P channel just passed 21VDC test.

Almost certain both silk screen mask for 12VDC zener diode direction is reversed on the printed circuit board cut out diodes and replaced with new in the opposite direction only fixed the P channel 😀

More soon

The N channel 6K 5watt resistor is a new bad part or bad circuit board connection, replacing part.

Both P and N channels operate now but scope says they are on the same phase of the sine, need to swap a diode or something 🤔

Have seen full power on both channels but something wrong with stereo output, this will be the third time I have run into problem, good news for me the previous second time around Diagram is correct and working.

Just need to recreate diagram to solve the current timing issue.

Tomorrow I will painstakingly mimic the diagram for the optic couplers also good news should only require a couple small adjustments to mimic operation 😀

More tomorrow
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Last look, mostly working need another day, Pictures: P FET working, N FET working, overview 98% completed.

Dual 27 volt test, failed sync test.

Swapping out the capacitor gave me a better square wave but right now stuck at 122HZ instead of 60Hz.

More tomorrow 😀


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Massive improvement in the circuit board, nothing like building a kit to figure out the needed improvements.

Tomorrow's changes will also be rolled into this circuit board design.

Improvements better holes for FETs and wires, capacitors, corrected silk screen to show corrected zener diodes, opto coupler are now six pin instead of four, and improvement in the optic couplers.

Serious take a look at the front view, over four hours of work recently 😀

More tomorrow


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