Author Options:

Tesla Coil with MOT's Answered

Hello everyone, I am looking to get some advise. I am building a Tesla coil and cant really get any transformers other than MOT. I have four MOT with all their other components (Capacitors). What I am asking is can I use these MOT wired up in a certain way and I also read somewhere that I would need to add a component to prevent the MOT's from sucking in too much power. If anyone out there can give me some detailed advise it will be great. I just started the build so pictures are coming soon. Thanks in advance to you all


you are set with just two mots simply parallel the primarys of the transformers ,*note : when paralleling the primaries make sure to reverse the leads of one of the transformers to make them in phase. then all u have to do is series the secondaries. Thats about it. You can get even more bang for your buck by using all four of your transformers or jus make a voltage quadrupler with the MOT capacitors and the diodes four mots will give you total of 8kv ,more than enough for a 4"-6" coil. check outs some quad mot tesla coils on youtube to see if they give the results u looking for

You could use just one mot to make the tesla coil. I know because 3 days ago I made my first tesla coil and it used a mot. The mot was powered with 12 volts. My coil is only 8 cm high and 4 cm around. You could pull an arc like 1.5 cm with your finger. It's really cool

what's your price range?

First off, if you want to use all 4 mots, make sure they all have similar ratings.  Also, when hooked up they should be in anti parallel-series (so it outputs -4000 to +4000 ac, NOT 0 to 8000AC, antiparallel puts less stress on the insulation).

to prevent it from sucking too much power, there are too meathods:

1) Resistive Load:  Placing a large resistor in series with all of the mots, such as a very large high power heating element (it must be able to handle the wattage).  This meathod is very inefficient.

2)Inductive Load: Placing a huge inductor in series with the MOT, this is much more efficient, but it's hard to find a big enough inductor.  Typically people use a MOT that has the secondary (HV) removed and hook up the primary in series with all of the other transformers.

Lastly, make sure that you will be able to power this thing!  The average household circuit can power a max of 2400 watts, this can usually only power 1 maybe 2 mots.  So keep this in mind.

Needless to say, careful with those things, they can kill you 10x over!

Thanks for the info, I guess the MOT idea is not going to work after all. Well guess I gotta look for something else to power this up.

Ignition coils!
They're dirt cheap, and they can run on 12v and yet squeeze out well over 20kv!
And if you drive one at high frequency, you can get a lot of current from it to!