i have a transformer 220v to 12v but i don't know how much current it can give . how can i know ? the only thing written on the transformer is the voltage

 

hi GB,
Measure and post the wire gauge of the 12V winding, we can then make an estimate of the current rating.
E

 

hi GB,
Measure and post the wire gauge of the 12V winding, we can then make an estimate of the current rating.
E

it is about 3 mm

 

hi,
If that is 3mm Dia or CSA [cross sectional area], this Wire Table link shows the current capacity.
How are you planning to use the transformer.?
E
https://www.engineeringtoolbox.com/wire-gauges-d_419.html

 

How big and heavy is the transformer?
A photograph with a size reference will help us estimate the power.

 

How big and heavy is the transformer?
A photograph with a size reference will help us estimate the power.

is this good ?and it weighs around 1.5 kg

 

I would put that at around 150va - 250va, see how that jives with the secondary voltage (gauge) at that Va.
Oops, that is in MM so that would be a little high, more like 75va.
Max.

 

Hi GB,
I do not agree with your 3mm wire dia, please recheck.
E

 

Also the lamination core width/height is 8mm, what is the depth of core?
Max.

 

Also the lamination core width/height is 8mm, what is the depth of core?
Max.

@MaxHeadRoom meant 80mm.

 

Hi GB,
I do not agree with your 3mm wire dia, please recheck.
E
View attachment 196756

you are right i'm sorry i made a mistake it is 4mm

 

you are right i'm sorry i made a mistake it is 4mm

It can’t be 4mm.
Try again.

 

It can’t be 4mm.
Try again.

why sir ? what is it supposed to be ? maybe it isn't the original wire because it is an old transformer

 

hi GB,
Its the solid copper windings that you measure not the flexible take off white cables
E

 

hi GB,
Its the solid copper windings that you measure not the flexible take off white cables
E

if that is the case then it is 2mm

 

why sir ? what is it supposed to be ? maybe it isn't the original wire because it is an old transformer

4mm is almost #6 AWG. That is almost as fat as a pencil.
There is no way any winding or connecting wire will be 4mm which is capable of handling 35A. This is what I would see on my car battery connections.

 

2mm is almost #12 AWG, good for 9A.

Don't measure the plastic insulation. Measure the enameled copper wire.
I am seeing 1mm = 18AWG, good for 2A.

 

4mm is almost #6 AWG. That is almost as fat as a pencil.
There is no way any winding or connecting wire will be 4mm which is capable of handling 35A. This is what I would see on my car battery connections.

i measured the wrong wire it is about 2mm

 

t

2mm is almost #12 AWG, good for 9A.

thank you but isn't there a formula to know the curent ?

 

There are numerous tables available on the net.