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Microwave Oven Transformer Stack Answered

This is my Microwave Oven Transformer stack. It is currently current limited using a heater.

There is approximately 10 36 watt 4' fluorescent tubes in a string around my garage that I am lighting with the MOT stack .

My MOT stack contains 4 Microwave Oven Transformers connected with their outputs in series and their inputs in parallel. They are mounted on plastic cutting boards. I am using threaded rod to hold the layers in place while the PVC pipe covers the threaded rod and it also supports some of the weight.

The output of this is approximately 8800VAC at 350mA The Input voltage is 240VAC

Thanks for looking, Please comment and remember to rate if you like it!

Just say if you want any pics of a certain thing, e.g. the MOT stack arcing to wood/metal etc. (I will try to get more pics of it arcing soon but it is hard to use a camera that has like a second delay before it takes the actual pic from when you press the button, stupid camera) ********************************************************************************************************** Edit The new pictures are of an arc between two carbon electrodes. The other pictures are of 12 fluorescent tubes connected in series but arranged in parallel so you can see them all


Could you please make a step by step

Man you did a good job! I wish I had more microwaves to salvage for their transformers.. :P

Thanks Plas, I will hopefully be submerging them in oil so I can run them with a bigger ballast, so I can get sparks like yours :-) It took about 4 trips to the tip (dump/waste disposal etc.) shop (they put things that people might want that was sorta in the garbage up for sale. I had mostly one each time, but sometimes I scored good and got 2 microwaves. (I have 5 MOT's all up), one that is going to be a ballast.)

Nice, I only use one transformer for voltage and the other as an ballast. Those huge arcs I got in the end was completely unexpected, I never knew why those arcs are huge. Until some helpful guy told me why...

Quoted by HighVoltageScience
The burned out sparkler make bigger arks cause
the burned part is a insulator and the wire is a
conductor that makes a capacitor and make's
bigger arks.

I don't know how to describe it in non technical form, so you will have to figure it out.. :P

I am (hopefully) going to the car boot sale in about a week, I might find microwaves there :-D

Yeah, I thought so... :-D When i get a chance, I am going to add two microwave oven capacitors to the circuit to get the transformer to it's resonance to make big arcs. BTW the link you gave me is blocked.. (I am at collage) So I won't be able to see it untill I get home which will be about a week. :-( I might forget it by then, lol

Have you tried using a proxy to get onto the sites? Have a look at the list here and try inputting that link I gave you. Look out though, because if your collage techies will probably start to block them, if they haven't already done so

That is also blocked, lmao Is there some kind of code that I can download onto my usb key back at home and take it to the collage computers to get some sites unblocked?

Hmm, I don't know if there is some kind of code to do that, sounds like your collage has some tight filtering. How about a forum topic?

It is pretty tight, and some features on college computers are locked by admin, which prevents me to play my browser game 'darkorbit', so I came back to Instructables instead :P

Are you using a laptop? If so why not try to make an antenna to pickup a signal from a nearby household?

How do I make an antenna for my mac laptop? My computer is picking up something, but it is too weak to use, lol

Also, the blocker is called: MessageLabs Look it up on goolge, its popular, I think, lol

Maybe, But it would be harder to get caps rated for the amperage, Idon't think it would be worth it, but that is just my 2 cents

Nice work with the MOT building Thermo. Hope to see it connected to the telsa coil at your building. I also like the pics of all of the light s connected together. GOOD JOB!

Haha, Thanks. I hope to have a Tesla Coil built by the end of the holidays, But wether or not it will happen is a mystery. I know my MOT stack is tough, because after I took it to school, I felt like taking it down teh steps, on the trolley thing, It fell off. and fell about 10 steps (concrete), And I didn't notice any damage at all.

How was the reaction of your class when you showed them? Dam , that must be pretty tough.

They were pretty amazed... After that, our science teacher showed us a vandegraff generator, really puny sparks compared to my MOT's...

Lol, your's compared to the vandegraff generator, I think that your's would win by a long shot. By that I mean in spark disposal ofcourse.

Holy zombie jesus! Its a thing of beauty! 8800vac?? OMG!

Thanks :-) Yep, Sure is 8800VAC. Tis a bit less than what comes from a NST or a OBIT, But the current is sure a lot higher than those other whimpy transformers... (Gotta be careful not to let the spark touch me and make my heart do the dance of death...)

Yeah, that would not be the best thing in the world, I wanna see more HV coolness

I'm trying to get some transformer oil to submerge the stack in, so I can run it at a higher current, and not be as worried about burning out the MOT's.

It will sure look more awesome when I start using a secondary shorted MOT to current limit it!

i just realized, you should burn some stuff with this >=D

cool! i probably wouldn't keep such a deadly device in my house

Haha, It sure is cool! It is only deadly when it is plugged in, lol. Anyways there are many things that are just as deadly as that in your household, you have a microwave don't you, probably a TV too, they are all dangerous...

yes, but my TV doesn't have it's HV coil exposed i usually mess around with 300V flash circuits, they have lots of voltage, but very low current

That is true.

What happens if you accidentally charge a small (or large) cap bank? This happens! Let me introduce you to Project Thumper!

Lol nice, I got one made from 20 flash caps, I use it to blow up stuff and coilgun experments. :-)

i let the magic smoke out of my charger circuits, so i have to go get more... i'll probably add another 10 or 20 caps to the circuit

I seem to let the magic smoke out of alot of my circuits too. Why not charge them with the mains (try the 220/240 outlet, current limit it with a light bulb in series ithe the rectifier, rectify it and you can charee a bank hell quick.

So if you put a light bulb in series with the rectifier and the rectifier charging the caps it will work.

light _ connection between cap bank and -
---()----------| - |-----------|

AC Rectifier cap bank

yeah i suppose it siphoned off too much power, if your capacitor bank isent too large there shouldent be that bad of a current surge when you charge it up

lol and the mini chargers take too long to charge the cap bank too.. So I use the MAINS for instant charging. :P Also the way I have desinged my cap bank, I can charge it up to 600v safely... Muahahah!

I'm gonna set up a mains charger tonight, I'm just worried that i'll over voltage the 330V photo flash caps.