I've just finished a module of Transformer theory in trade school and was
hoping to try some of it out.
I plan on experimenting with winding my own toroidal power transformer.
I require a 1:2 step up at 20V 150hz supply aiming at 150-300VA or so.
I have found a general ballpark equation to calculate primary turns for an
EI type transformer which goes like this:
is N = (E · 10^8)/ (4.44·f·A·B),
N= number of pri turns
E= supply voltage
A= Cross sectional area of core (I think in square inches)
B=max flux lines = rough figure of 60,000
Using a toroidal core with a CSA of 1sq" it gives me 50 turns for the
Is this equaiton correct?
Is the value of B ok for say a Mains 300VA toroidal core off the shelf?
If anyone can help me answer these two questions, or point me somewhere that
can I would be very greatfull.
19 years ago