The balloon story is total BS from a rocket dork. However, under heat and pressure you CAN get nitrous oxide to go into full detonation. Rocket dorks found that out the hard way with hybrid experiments.
Would an RC servo tester generate the right PWM signal? That would be a really easy and cheap way to control it if it does, it has a little dial to set the PWM value. I got one of these newer MOT units recently and couldn't for the life of me get it to work, not knowing about the PWM thing, so I scavenged it for components but I'll keep an eye out for another one to experiment on, being able to adjust the power level would be great, it would have worked well for a capacitor bank charger I'm putting together. These do come with some excellent components though, I got a great ferrite core, a good length of fine magnet wire, a few feet of Litz wire, a mosfet, a 1000V bridge rectifier with heatsink, a bigass resistor, a couple small capacitors and a few other odds and ends, at least it wasn't a total loss. Now I'm using the 1KV rectifier on my capacitor bank charger that's using a regular iron-core MOT connected to a 500 Watt variac to dial in the 475 Volts I need for the caps, with a couple light bulbs in series on the primary to get my current way down. It's going to be fun, the bank has nineteen (would have been 20 but one was bulging😒) 422uF caps at 475 Volts each, with a total capacitance of 8,000uF so each pulse will be just shy of 1KJ.
Whats on the 3 signal wires to the MW board? 220hz sig, ground, and what else? My exp goes back yrs with the big transformers, now I need to retrain on these.
Great tutorial Mr Poulton. I got a panasonic inv to run after watching your video. I don't have to tie the fdbk signal to common through a 1k resistor on my unit. This signal appear to go through an optocoupler output . Maybe other inverters are different. Tks for the video, good job !!
So the term "inverter" is a lie, and these actually use the opposite (a rectifier) to work. And pulsed DC is not the same as AC. Taking AC and turning it into DC is exactly the job of a rectifier. There ought to be a law prohibiting deliberately misleading nomenclature. Think about it: an inverter is what creates AC electricity. To apply an "inverter" to an AC power source is worse than pointless. I think I'll manufacture a switchmode power supply and call it a "Transformer®". 🙄
@@poultonm thank god for that, I'm a layman so I didn't have a clue, so when it was worded that way I was perplexed, cheers,I can take it apart now (after discharging the PCB)
This is a very informative video. Thanks for the hack. I have one of these inverters from a Panasonic NN-H665BF microwave. I also want to repurpose the timer controller from this microwave on a separate project. However, the 3 lines from the main PCB to the inverter and/or the line voltage connections to the inverter are required somehow to feedback to the controller that the inverter is powered up. If these lines are not completed, the timer always stops after 3 seconds. Do you have any idea how to bypass this function on the timer/main PCB? I thought it might be that the orange 110 hz square wave line needs to be simulated by a custom 555 timer circuit?
I have no idea. I did not attempt to use the microwave's control board at all. However, I would start by simulating the same signals and voltages on its interfaces that you find during normal operation. The PWM signal might be important.
Did you end up working it out ? I'm not having any luck. Mine read 220hz 30% duty when attached to inverter but when I disconnect and give it that with a generator it still stops after 3 seconds........
Nitrogen doesn't burn and it actually cools down the oxygen fuel mix to help slow down pre-ignition in an engine . If you want a boom add some flammable gas in the balloon with the nitrous oxide .
This is amazing. I was wondering why mine didn't work and you explained it all so well. (Needed a signal 220Hz signal.) Thanks also to Poultonm for that. I really like your mods and appreciate the help you've given me even 8 years after you posted this video. :D
Hello Dear Inverter Enthusiasts I have been designing a controller for a National inverter board with two IGBTs and I have not yet concluded to the exact timing for the duty cycle because I do not know the transformer and magnetron’s parameters. Any suggestion to tackle this problem would be highly appreciated. Thank you for taking time to read this script.
Hello Dear Inverter Enthusiasts I have been designing a controller for a National inverter board with two IGBTs and I have not yet concluded to the exact timing for the duty cycle because I do not know the transformer and magnetron’s parameters. Any suggestion to tackle this problem would be highly appreciated. Thank you for taking time to read this script.
can anyone enlighten me on the 555 timer circuit for this as I’m I’m new to electronics ,correct me if I’m wrong but 555 timer only can go to a minimum of 50% duty cycle so how did he manage to reach a 43% duty cycle on a 555 timer, is there something I’m missing?
Hi i have stripped a Panasonic microwave 1000w as i was going to build a welder but turns out the microwave is an inverter model so dont think i an use it for that but i have all the parts which are no good to me and have not been touched just stripped from a fully working system if you would like the parts pls msg me as they are no use for my projects and sounds a bit scary tbh.
Poultonm; thanks for your video, it was very illustrative, but I was wondering about what you said in the vid description; do you think replacing the high voltage transformer with a cooper loop will do the same job as a induction heather or it requires anothers modificions ? Thanks in advance for your comments.
Hi good day i have the same microwave but no display on controller board and i saw smoke coming from microprocessor on controller board , can i set up a seperate controller board using the 555 timer ic to turn on the high voltage circuit ? Can you please assist me with the shematic diagram.thank you.
Are you still out there Poultonm? These 2 videos are among the best ever, informative, helpful and motivating. Please do more on whatever other projects you've been in to. In 2011 nobody expected such treats on YT and few actually searched for them but now you would have an army of appreciative minions.
the insulating compound you have used for the IGBT becomes conductive with high voltages. In the high voltage industry, these materials are called "semi conductive". Materials like carbon compounds which are normally a dielectric (dielectric is an insulator) using lower voltages can be semiconductive with high voltages, however, they can only be identified as semiconductive using a hitpotential test set or with what's called a Megohmeter or Megger (this megohmeter is not like a normal multimeter that tests the resistance using a function to do so in the megaohm range , as they normally only push 3-5 volts through the leads to test these resistances) The Megger uses high voltages to test the impedance of these material in megaohms by pushing specific voltages in the ranges set by the meter. These levels could be 1200 volts up to 15,000 volts.
Hi, I have seen your Utube demo for Microwave oven Inverter hacking - the new MOT, and pleased to watch the very informative illustration. I would like to know whom and how should I contact to clarify a problem about my Inverter Grill M.W. No.NN-GD371M. Thank you JP
Hi friend, Excellent work! I came across your RU-vid just lately and am enjoying them thoroughly. Thank you for your skillful engineering work. I think +5V at pin 3 after the AC power switch on will work. Don't you think? Somebody overcame the cutout problem you experienced by modifying the PWM TTL signal input . Thanks again Nwin
nwintran Sorry I missed Anton's comment on when he applied +5V to pin 3 and the inverter did not work. Just now I was assured by a Panasonic microwave inverter oven technician that if one turns on the Panasonic Inverter oven then select full microwave power (100%) then the full power will be on in few seconds seconds. Does it mean the same as applying +5V to pin 3 in a PWM controller.
nwintran Sorry I was not quite correct in my last sentence in a previous comment. For full power the duty cycle of the PWM must be less than 90%. This means that applying +5V DC is not exactly the same as a 90% duty cycle PWM TTL signal.
Hi, I want to do something similar, but instead of using the inverter ps, I'm trying to use the oven with the old transformer, capacitor and diode just to eliminate the inverter ps. I connected a 1k resistor between orange and brown and it worked, but only for 23 seconds, then shut down. Have any idea what is going on here? Thanks.
This would not be a good choice for an ozone generator. Ozone generators require high voltage at low current, and total power much lower than what this is designed for. A flyback transformer would be a better choice. This thing does not produce enough voltage, and is far too dangerous for that application.
can you show us how to bypass the duty cycle circuit? is it possible to simply power the inverter with the microprocessor board or control panel of the microwave
I would like to talk with you by email, could you email me back at robotics (at) lavabit (dot) com I have a project I would like to talk with you about, We need a circuit designer.
I would assume it performs very poorly, probably by self-destructing. It might survive since it's a constant-power regulator, but that would be well outside its normal operating parameters so I would not expect it. The results will not be as impressive as you hope, since iron core transformers handle very high peak powers that make impressive arcs. This thing will never push much more power than it's designed for.
The control circuit is at least as simple as anything you could reasonably want to power with this thing... It's about the simplest project possible using an integrated circuit. There are literally dozens of different ways to build it that would work. All you need is a square wave with the proper characteristics. A quick google search will turn up plenty of possible approaches. I just googled square wave oscillators and PWM circuits to find a solution that would work with parts in my bin.
Sure! As long as you want your radio transmitter/Tesla coil/induction heater/other contraption to be programmed and operated like a microwave oven. I can't imagine that would be very useful though.
I just found a post on fusor.net that says: Pin 2 is a common lead. Pin 1 is driven through an opto-isolator with a signal related to power output. Pin 3 is supposed to accept an oscillatory TTL signal whose duty cycle determines the power level, which again is coupled to the board control chip via opto-isolator. However the board produces full power if +5VDC is applied to this pin. The AC mains must be hooked up for some small fraction of a second before 5V is applied or it won't be recognized
