With a transformer the amount of turns changes the voltage, but what happens if your ratio is the same between turns, i.e 10 to 1 or 100 to 10, same ratio. What does this change, CC or CV or duty cycle (or something completely different)? Regards

 

The link here has some related information.
Maybe there is more to your inquiry?
Turns Rule

 

The link here has some related information.
Maybe there is more to your inquiry?
Turns Rule

Yeah i've seen those calculations before, quite handy it all being on one page. But using those calculations 10/1 or 100/10 both gives 10, so this is why i think there must be something else to play.

 

... the total resistance of the wire in the coil determines the level of current that can be used without causing excessive heat build-up.
The heat Q, due to current flowing in a resistor is called Joule Heat and is given by the formula:

\( Q=I^2R\)
in units of watts or their equivalent

 

If you are using the same core, then the DC resistance of the windings will be different, the inductance will be different, and the inter-winding capacitance will be different. All these things will affect the performance of a transformer as a function of current and frequency.

 

Yes there is. It is mostly about what they call Bmax, which is the maxium flux density that the steel core can handle before it saturates.
So with only 10 turns on the primary the transformer core may saturate and that means the transformer can not function like a transformer instead it acts like a very low ohm short circuit primary.
With 100 turns, the primary may not saturate and so it may work right.

It may even take 200 turns, or maybe only 50 turns, but to find out you have to know the max flux density for the type of core you are using for the transformer. Most power like transformers have a Bmax of around 20kG which is 20 kilogauss which is 20000 Gauss.
The formula then is:
B=1e8*E/(F*A*N*4.44)
where
B is in gauss
E is rms sine wave voltage in volts
F is frequency in Hertz
A is cross sectional area in square cm
N is number of primary turns.

It is best to keep B around 15kG to avoid problems with variations due to environment and other. Thus you can start with B=15000 and solve that equation for N and that is the minimum number of turns needed for that given core.

The DC resistance is made according to what is needed in the application. If you need heavy wire you use heavy wire but you may have to increase the core window area which means getting a different core in most cases.
Depending on frequency you may have to wind using two wires or more wires at the same time to avoid losses due to skin effect. This becomes more important at frequencies above 100kHz but with higher current transformers it could be much lower.

 

... also, any waveform with a sharp right angle shape, like a square wave or a pulse modulated shape is the result of a sum or composite of sine waves at multiple frequencies, and consequently is not appropriate for ordinary use with a transformer.
Another article about it here:
square wave

 

Yes there is. It is mostly about what they call Bmax, which is the maxium flux density that the steel core can handle before it saturates.
So with only 10 turns on the primary the transformer core may saturate and that means the transformer can not function like a transformer instead it acts like a very low ohm short circuit primary.
With 100 turns, the primary may not saturate and so it may work right.

It may even take 200 turns, or maybe only 50 turns, but to find out you have to know the max flux density for the type of core you are using for the transformer. Most power like transformers have a Bmax of around 20kG which is 20 kilogauss which is 20000 Gauss.
The formula then is:
B=1e8*E/(F*A*N*4.44)
where
B is in gauss
E is rms sine wave voltage in volts
F is frequency in Hertz
A is cross sectional area in square cm
N is number of primary turns.

It is best to keep B around 15kG to avoid problems with variations due to environment and other. Thus you can start with B=15000 and solve that equation for N and that is the minimum number of turns needed for that given core.

The DC resistance is made according to what is needed in the application. If you need heavy wire you use heavy wire but you may have to increase the core window area which means getting a different core in most cases.
Depending on frequency you may have to wind using two wires or more wires at the same time to avoid losses due to skin effect. This becomes more important at frequencies above 100kHz but with higher current transformers it could be much lower.

Wow now thats a reply! Thank you all others that have responded also.

 

The main difference is the inductance. If you wind a 60 Hz transformer with only 10 turns, it will look like short to an AC power supply. The inductance needs to be high enough to keep the idle current within reason. Note that 100 turns has 100 times of the inductance of 10 turns, because the inductance is proportional to the square of the number of turns.

If you are dealing with MHz, 10 turns is often more than enough.

Bob