Directed Electronics A1200/4 - Manual (Page 12)

CHARGING SYSTEM
If your total current draw is over 100 amps ( or total output power is
over 600 watts ), you are probably exceeding the capability of your
charging system. Dimming lights and fluctuating voltage are solid
indicators that you need to upgrade your alternator, battery, or both.
You should also check the condition and current capacity of the
stock battery negative cable and connections, and replace or
upgrade as necessary. Keep in mind that your amplifiers simply
convert electrical energy to acoustical energy, and any electrical
deficiency will compromise the performance of your sound system.
For more information about charging system upgrades, see you
local authorized
Precision Power TM Dealer or call Precision Power TM
Technical Support at 1-800-62POWER x2033 .
CURRENT DRAW
The following is a basic formula to be used as a guide to determine
current draw. Your new amplifier is more efficient than most other
amplifiers. This formula is to be used as a guideline. Using wire of a
larger gauge can only improve the current transfer of your system.
Do NOT use smaller wire gauge.
Total RMS output X 1.5 = Total Input Wattage
Total Input Wattage = Current Draw (in Amps)
Supply Voltage
Example: Your new amplifier has four channels at 250 watts per
channel RMS rating into 4 ohms (250X4 = 1000 watts).
You would use the formula in the following way:
1000 W X 1.5 = 1500 watts
1500W = 125 Amps total current draw
12V
If the same amplifier is driven into a 2 ohm stereo or 4 ohm mono
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