need help on how to coil a transformer and whats the difference of a iron core and a ferrite core transformer...

 

Kulas,

Do you want to make a tranformer from scratch or do you want to fix a damaged coil? There are usually winding machines that will do the job, I do not recommend hand-winding because it usually does a poor job and it is incredibly time consuming.

Iron and ferrite cores are of a different material with different characteristics. I am not sure about the differences, but I know they must exist. I think the permeability of the materials are a big factor and the way it couples the flux is different. I think ferrite is a lot more brittle then iron, and i believe it might be more suitable to high frequency coils.

Steve

 

thank you for wasting some of your time on me. I'm so new with this stuff. I wonder if you could help me find a substitute for a ferrite core transformer(RM10 core kit) because there are no shop here that sells this stuff. Or some info on where a could scrap this material from, what appliciances or devices. thank you so much...

 

No problem

I do not know any information on the RM10 core kit, so I cannot find a substitute. Do you know any information on it? Is it a ferrite toroidal core with some magnet wire to make your own transformer?? I never would a tranformer like this, but I have heard many success stories. A lot of the times people use these custom toroids in switching power supplies for car audio.

Steve

 

ferrite is more of a steel term. it is one of the "substructures" in steel, along with cementite and pearlite.

 

Steel cores have losses due to induced currents that circulate within the steel. These currents produce heat, weaken the magnetic field and thus waste energe. The loss of energy increases with frequency.
There are special kinds of steel (weakly magnetic) for transformers, but they do not reduce the losses. For low frequencies, say 50/60 hertz, this is ok; all commercial transformers for line powering are built that way.
If you go to higher frequencies (ie above 100 Hz) these losses become significant.
In ferrite material, there are ferrous and other oxides used as magnetic material. They are non conductors, so there can't flow any current - no losses. But ferrites are difficult to get in shape - you can't bend or weld them, so transformers are built form premanufactured parts - coil kits.

This is at least what I learned about these thingies.

If in doubt, always obey the manufacturers recommendations for frequency range, wattage and number of turns. Otherwise, the results will transform some energy - voltage and current - anyway, hut the losses increase.
Also notice that the inner windings of a coil usually burn first as they do not get much cooling - wrong operating parameters worsen the effect.

For winding crude transformers myself, I attach the ferrites to a battery driven screw driver, and count the turns with an old (mechanical) bicycle tachymeter. Just be quick with laying the windings side by side :-)