# battery charger how work

Discussion in 'Power Electronics' started by mrel, Sep 18, 2012.

1. ### mrel

103
0
Jul 2, 2008
Hello
Woodward Schumacher sure 1000 Fire automatic circuit breaker 10 amp battery charger model WS 1010 input 60 cyclce 117 vac 2 amp Output 6-12 VDC 10 Amp.
Question is input voltage 117 vac and 2.amp,And output 6-12 Vdc10Amp.
How did the battery charger give more ampere output (10 amp) when the input was only(2 amp) ?
mrel

2. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,496
2,837
Jan 21, 2010
It uses an inductor to store energy and release it.

the energy input is 117V * 2 A = 234W. The output energy is 12V * 10A = 120W. My guess is that the input current is only slightly over an amp in normal operation.

It is almost certain that the type of inductor used is called a transformer (there are others). This takes AC of one voltage and produces AC pf a (usually) different voltage. Small losses aside, the input power is equal to the output power. If the output voltage is lower than the input voltage, this implies that the output current is higher than the input current.

3. ### akida

9
0
Oct 4, 2012
P = VI

(Power = Volts x Amps)

For the same power, if one goes up the other goes down and a transformer makes this possible.