battery charger

Discussion in 'The Projects Forum' started by archie79, Nov 24, 2012.

  1. archie79

    Thread Starter New Member

    Nov 23, 2012
    Im kinda a newbie in the electronic world, so i apologize in advance if i seem to be talking nonsense. I have recently been looking at diagrams for battery chargers, and i built one the other day as a simple project. It worked fine, so that got me wondering about the chargers with the "ump start" capability.

    I cant figure out how they get so much current out a step down transformer, or do they just use a large bridge rectifier off the main like car alternator? If anyone has a schematic for something like this i would like to build it as a project, or at least study it as a learning guide.
    thanks in advance.
  2. donpetru

    Active Member

    Nov 14, 2008
    First, please show me the scheme that you did and after that I tell you what you did wrong. And just after that, I can show you another electronic diagram battery charger.. maybe a better electronic diagram.
  3. wayneh


    Sep 9, 2010
    If it's drawing 10-15A from the wall (the max for a normal service outlet) and stepping it down to 14V or so, there's easily over 100A available. The units with still higher amps usually have an integral battery inside - it's just a mobile spare battery with leads attached.

    Welding power supplies get to even higher current levels, at lower voltages.