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How do VV/VWs handle ohm's law?

Discussion in 'Ask FC' started by solomon7, Aug 5, 2014.

  1. solomon7

    solomon7 Member

    Everything I've read says all VV/VW are either or, You set watts and the 'chip' adjust volts following ohm's law to balance or vice versa.

    Therein lies my confusion about devices' actual capabilities.
    For example:
    With an MVP's 2.0's 3 amp battery max cutoff, it can't push 11 watts really on a .7 ohm atty.
    At 11W It would be drawing 3.96 amps.

    It can't do that with a 3amp max, so the chip regulates it to below 7 watts to be below the 3 amp max., even though the display will read 11 still. Right?
    In voltage mode I can set it to 5 volts max. that works out to over 35 watts following ohm's law!!
    I thought it had an 11 watt max.


    That make sense or am I WAY off? Will it just run what I tell it, and if so will running a .7 atty at 11 watts drawing more amps than the battery is rated damage the device or battery's longevity?
    What are these thing's actual maxes? How do these things actually work that stuff aout?
    Last edited: Aug 5, 2014
  2. 1GreatToke

    1GreatToke Well-Known Member

    For perspective i'm an electrical engineering student in his third year.

    my guess would be that the regulators are built in and definitely not going to let you do whatever you want on the screen. The display will say its putting out whatever it is but trust ohms law and what the regulator says it can do.

    For example, you may set it to 5v and the mod may very well try to put out 5v, but in the milliseconds after u push the button (or nanoseconds depending on the circuit) the current will reach the max that is physically built into the circuit, therefore it will drop voltage to match the 3A max current.

    Also dude, why run sub ohm on a regulated mod? isn't it kind of the point to sub ohm on a mechanical so u can push some heavy current?
    solomon7 likes this.
  3. 215z

    215z Well-Known Member

    MVP displays target potential/power, not actual #s achieved.
    solomon7 likes this.

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