Newbie Help

159

02:15:27

I'm new to electronics and still trying to nail down the basics.  I've got a 12v ac/dc adapter (500ma) and i want to power a small computer fan as a test.  It has DC12V and 0.24A on it.  Here's my question.  I can't find a way to specify in the power on everycircuit the amount of amps provided by the power supply.  In here i just put a dc motor as that's as close an item similar to what i have.  How do i specify how many amps this adapter is pushing out so i can get the right resistor and not burn out my fan?  Again, i'm a complete n00b so any advice would be great!

published 8 years ago

rgrevelding

8 years ago

The amperage that will be drawn is based on the load. The 500ma rating on the power supply is the maximum output it's rated for. You can change the current that will be drawn on the motor in everycircuit

rich11292000

8 years ago

To answer you specific question: no resistor is needed for a 12 volt adaptor to drive a 12 volt motor. Its all 12 volts here. Your motors full load ampacity (FLA) is .24 amps, you will expect a in rush current around %200 more than your FLA, this means you will be .96 amps. This in rush current may cause some problems at start up as you will be exceeding the 500 mA. The adaptor transformer has internal resistance, once the amperage exceeds its rating the voltage will drop due to the internal resistance, this will cause wattage to be wasted in the form of heat, heat equals premature failure. But it should be able to hang in there a good while.

rich11292000

8 years ago

http://everycircuit.com/circuit/6036432599908352

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