An technical electrical question (not house electricity).

[SallyValley]

I have a small appliance and it runs from a small transformer that puts out 12V. 0.4 amps.

I know a car battery puts out 12V but don't know anything about amps.

My question is: Can I use the car battery to power the appliance directly or will the higher amperage (I'm assuming) cause problems?

Hubby says I can use an inverter and then plug the transformer into that to power it.

Thoughts?

Thanks.

Sally

[WA4KDC]

A car battery's "12 volts" is actually 13.8 volts when the engine is not running and 15 to 17 volts when the engine is running.

IF your appliance can tolerate these sorts of fluctuations in voltage, you can safely run it directly from a car battery (cigarette lighter plug.)

.4 amps is nothing to a car battery, they put out hundreds of amps when starting the engine.

Your appliance will draw whatever amount of current it needs.

I am assuming you mean 12 volts DC not AC. If it needs AC then it cannot be powered directly from a car battery.

[Mainecoons]

The small transformer is going to be putting out 12 volts AC unless it also includes a rectifier (unlikely). Amperage is not the problem and a car battery that is not charging should not overvoltage the appliance but it may only run on 12 volts AC.

[Xcalaker]

"Your appliance will draw whatever amount of current it needs."

Best answer.

FYI..I doubt your 'appliance' requires a 12V .4amp AC power.