# electromagnet power

Discussion in 'Electronic Basics' started by lerameur, Jun 5, 2008.

1. ### lerameurGuest

HI all,

I just build two electro magnet with the same Gauss output, They have
different iron core with different gauge size. They both output the
same gauss with a 12v battery. I wanted to know if using a 24v
battery, should I still be getting the same gauss?
The finding of the same gauss was done by trial and error, I could not
find a web site explaining size of core Vs gauge wire with the gauss
output, anybody has a link to that, is there a general formula?
thank

K

2. ### lerameurGuest

http://www.coolmagnetman.com/magdcem.htm

k

3. ### terrySGuest

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Not quite sure of your question:

Be careful:

If you apply twice the voltage to most citcuits twice the current will
flow.

And you will be applying four times the power (watts) to the circuit.

Power (which is measured in watts) = volts multiplied by amps.

So at 12 volts. 12 x Amps = W watts.

And at 24 volts 24 x Twice amps = 4W watts.

Learn Ohm's Law: Absolutely basic to electrical voltage/current flow.

Question: Re; your two electromagnets. Both on 12 volts.

Is one taking more current than the other but has fewer turns of
thicker gauge wire?

Also is the one with more turns taking less current at 12 volts,
because it is wound with thinner gauge wire. Therefore having a higher
electrical resistance to current flow.

Also that's not the whole story! It may be that you can only magnetize
the metal cores to a certain 'saturation' point. Applying further
electromagnetic power (volts times amps) to the circuit may only
result in heating.
Over heating will tend to destroy the magnet wires and could in some
cases cause a fire.

Am sadly out of date (some 55 years ago) but vaguely recall a formula
(equation) that had 'Electormotive force' proportional to things such
as the amount of current flowing through the coil, the number of turns
in the coil (possibly squared?) , all modified (divided by) by the
size of and permeability? of the core material.

If can find the equation will post it here. But try looking up
'Electragnetic Force' on Wikipaedia or something.

Post back here what you find.

4. ### EeyoreGuest

Isn't it Teslas these days ?

Graham

5. ### Bob EldGuest

Tesla is an MKS or SI unit. Gauss is a CGS unit. a Tesla is 10^4 Gauss.
What's 10,000 among friends?

6. ### lerameurGuest

The problem I had is that the two iron core where of different
thickness. Both had the same size, but one has very thin waffle, like
a 100 of them , the other iron core had about 15 waffle. Again both
the same size. From what I experimented, thinner waffle produced a
better electromagnet. Am i right by saying this?

ken