Round 2.. fight

 

Ok I tried. No other transformer while still heavy

 

You do realize that you have to remove the old secondary winding to use an MOT as a low voltage transformer, right?

And that your new secondary will only have a few windings?

Bob

 

You do realize that you have to remove the old secondary winding to use an MOT as a low voltage transformer, right?

And that your new secondary will only have a few windings?

Bob

Thank you for the heads up. Yes I am, after all this time spending on transformers, fully aware of that aspect.
And there lies the problem. How do I get 35mm2 wires in tiny MOT's?

 

And that your new secondary will only have a few windings?

as far as my knowledge has gotten so far I probably need a lot more of windings on secondary, in the MOT context, because of the wind count in primary.

Probably far more than I need now with a wind count of around 1234 in primary
EDIT: now no longer 1234 winds atm. since I have now placed prim coil on top of 2nd

 

The transformer you pulled out is not a MOT. Yes, it is a transformer and yes it came out of a microwave, but it is a control voltage transformer. Only 20VA. A MOT is 1,000VA+. If there is no yuge iron boat anchor hiding inside, then what you have there is an inverter microwave. MOTs will be inside older microwaves and cheaper ones. That one looks fairly fancy.

 

The MOTs we are talking about are about 15 cm cubes.

Bob

 

How to obtain unobtainium then?

Ok So this parallel MOT aspect is still going on strong. please do not worry.
But I have received a package today and I wonder what's inside. I have not checked yet which of the components it is but I am sure it is related to this project.

I will, if need be create 20 separate parallel transformer projects to make sure this show stays on the road.

 

as far as my knowledge has gotten so far I probably need a lot more of windings on secondary, in the MOT context, because of the wind count in primary.

Probably far more than I need now with a wind count of around 1234 in primary
EDIT: now no longer 1234 winds atm. since I have now placed prim coil on top of 2nd

Your idea of # of turns required in the primary is solely from experience gained with your iron powder core and does not translate to # of primary turns required in a MOT. If you manage to find a MOT don't touch the primary. It already has the perfect # of turns for the core that it's installed in.

BTW... all this MOT stuff is focused on MOTs because you're talking to people who have garage sales. MOTs are plentiful here, ubiquitous. So that's what we default to. But it sounds like your situation is different so you should know that all this applies equally to any commercially made transformer you can find. If you can find on ebay within driving distance (or cycling distance maybe) any kind of 50/60Hz power 500VA+ power transformer or control transformer, you can tell us it is a MOT and we will be appeased and you will be transforming voltage efficiently. Just don't get a potted power transformer, they are full epoxied sand that makes your brain hurt when you try to burn it off.

 

How to obtain unobtainium then?

Do you at least have a local community forum? Facebook marketplace? Craigslist? Somewhere online that local people post things for sale? You could browse the listings and/or place a want ad: "wanted: old broken microwaves. Will remove for free."

 

you know what. I strongly object to not being allowed to place one liners.

Now I am adding new thoughts I have to older posts via edit and most my dear participants will therefore miss it

 

Do you at least have a local community forum? Facebook marketplace? Craigslist? Somewhere online that local people post things for sale? You could browse the listings and/or place a want ad: "wanted: old broken microwaves. Will remove for free."

yes we have one bought by ebay if I am not mistaken marktplaats.

it is the best running, other wise ebay would have never bought it

 

you know what. I strongly object to not being allowed to place one liners.

Now I am adding new thoughts I have to older posts via edit and most my dear participants will therefore miss it

I wish you lived near me I would donate 20kg worth of MOTs to your cause.

 

Do you not have scrap yards? What do people do with microwaves, dryers, refrigerators when they die? Where do they go? Can you go there and inquire? Around here they go to a scrap yard where they might sit around for a day or two before being crushed. They will gladly sell us anything we want for just a bit more than scrap price.

 

View attachment 266470

Was this a full size or 800x600 image? If 800x600 I will try and find a way to automate downscaling before posting. If full scale then let this be an example why we need full resolution images

 

Do you not have scrap yards?

I can ask the municipality waste prossesors, which also have a dedicated inlet for things like that.
my best guess is that they already know how to make a profit so I am guessing they'll send me home without MOT


But one has got to try to know for sure

 

Was this a full size or 800x600 image? If 800x600 I will try and find a way to automate downscaling before posting. If full scale then let this be an example why we need full resolution images

2048x1536

 

Discussion should remain on the open forum, it is for the entire community, not just for you.

Bob

 

yes I agree. but when I am open like i am then I get in trouble for it. that is quite a conundrum I am in.

i mean on the one hand I may not post one liners and on the other i may not edit my older posts, which I recently do to avoid one liners.

please anyone. help me out of this mayhem

I am using the words may not far too liberal here. I am motivated to not do so is more like it

AAC forum is not a chat box.
Each post should be a meaningful contribution to the technical aspects of the topic.
Please comment on technical, electronics, engineering, etc. and please stay on topic.

 

AAC forum is not a chat box.
Each post should be a meaningful contribution to the technical aspects of the topic.
Please comment on technical, electronics, engineering, etc. and please stay on topic.

Agreed.

Here goes.

So I have now all the components to make this setup even saver.
I have an inrush current limiter, I have several 3.6V 1F caps, I have the new rectifiers that got suggested.
I have a breadboard in the meantime ( only to figure out that these boards do not really work for high amp applications hahhah)
I have got several thermal fuses.

I basically have everything in terms of making sure this system does not become a dangerous unbleached safety hazard.

What's next? I am considering getting 500 meters of insulated 1mm2 wire for the prim coil. so that @Hymie 's worries are dealt with. Because now I am using 0.79mm2 (1mm diam) enameled wires for the prim coil and as it is being moved around alot there might come a time in where things start to short out. point WELL taken @Hymie

Also I will be a bit slower with posting images. It's just such a hassle to scale them down.


It's only recently I learned that there are inrush limiter calculators. Although I have not found one yet But I am on the case if the ones I have now is not suitable.

The blue toroidal coil is going to be used to measure how deep the magnetic flux goes inside the coil. Flux penetration should not matter (as far as my understanding goes) regarding of the medium it travels though so I think it is ok to measure it whether it is in mid air or covered with powder or not.

Based on my findings I will figure out what best size core to use.

I have heard in a long forgotten conversation something about conductance measuring. If one could refresh my mind again please?