2007-03-02 02:02:59 · 8 answers · asked by usama s 1 in Science & Mathematics ➔ Engineering
You can't start a car engine from a charger, it's output will only be about 3 - 8 amps max. The starter motor will draw upwards of 200 amps!
2007-03-02 03:43:47 · answer #1 · answered by jayktee96 7 · 1⤊ 0⤋
You need to read the manufactures rating plate on the starter motor. This will tell you what voltage is required and maybe the current in amperes. It might give the power in watts or Kw .If so then to get the current divide this number by the volts. Remember 1 Kw=1000 watts .The charger will need to deliver about 10 times the current rating to start to turn the engine.
2007-03-02 04:05:16 · answer #2 · answered by mad_jim 3 · 0⤊ 0⤋
Almost all car batteries are 12 Volt, however they vary widely in amperage based on the size of the automobile engine and the electrical requirements of the starter.
It's also usually a good idea to oversize the battery (alternator and wires as well) if you are going to be hooking any large loads to the car - like stereo amplifiers.
2007-03-02 02:36:05 · answer #3 · answered by joemammysbigguns 4 · 0⤊ 1⤋
a full battery is 13.8 volts... it drops to 12...
given the starter is around 17 amps, plus the requirements of the rest of units drawing charge... lights air con, fans blah blah blah.. and if the battery is flat... add the draw on the alternator, which will be banging out upto 45 amps as soon as it comes upto speed.
obviously bigger cars use more power.. turn everything off and you may get away with 30 amps.... and you still have to have a battery connected... your car systems are DC... i know the charger is DC, but battery DC is smooth, whereas charger DC has a pulse... and ECU's dont like it...
2007-03-02 03:35:26 · answer #4 · answered by Anonymous · 0⤊ 1⤋
That depends on the starter motor, which depends on the size of the engine.
The starting current is assumed to be about 300 to 500 amps, and that kind of current draw will lower the battery voltage from it's peak 13.2V.
Assuming that the amperage is 400A and the voltage holds at 10V, you are looking at dissipating 4,000W (4 Kw)
That also shows you, that unless you have a huge charger (400A capacity), mostly you need the battery in conjunction with a charger that contributes to the starting current, to turn the starter motor over.
2007-03-02 02:15:58 · answer #5 · answered by Anonymous · 2⤊ 2⤋
What does your battery say? Your starter takes 12vdc. Usually, 700 to 900 cold cranking amps. If you don't have a battery, your going to have a hard time.
2007-03-02 13:16:30 · answer #6 · answered by Snowman38 1 · 0⤊ 0⤋
Batteries can be 6V, 12V or even 18V, but usually 12V. They also can have differnent ampage, but often around 300A. They are designed to deliver a large amount of current in a very short amount of time.
2007-03-02 02:15:45 · answer #7 · answered by Marky 6 · 0⤊ 1⤋
most batterys are 12 volts.
2007-03-02 02:12:51 · answer #8 · answered by Mike E 3 · 0⤊ 1⤋