# transformer amperage

Discussion in 'Electronics Homework Help' started by J.E, Apr 1, 2011.

1. ### J.E

3
0
Apr 1, 2011
how do you calculate primary amps to secondary amps for a transformer? Is there a standard ratio for all transformers? 2. ### duke37

5,364
769
Jan 9, 2011
No.
Transformers are designed for a particular purpose. If the voltage is transformed down by a factor of 2, then you would expect the permitted output current to be increased by a factor of about 2. With multiple secondaries, the permitted current in each secondary will depend on the wire diameter (resistance).

3. ### lexroxas

37
0
Apr 15, 2011
The primary and secondary currents depend on the turns ratio of the transformer. The turns ratio is N1/N2. N1 is the number of turns of the primary windings and N2 is the number of turns of the secondary windings. The current to turns ratio relationship is given by the formula: N1/N2 = I2/I1. I2 is the secondary current and I1 is the primary current. Also, the voltage to current relationship is given by the formula: V1/V2=I2/I1. V1 is the primary voltage and V2 is the secondary voltage.  