Wiring, Back to contents – Precision Power PC4200 User Manual
Page 6
The following is a basic formula to be used as a guide to determine current
draw. A 50% amplifier efficiency rating is used as an average. Your new
POWERCLASS
™
amplifier is more efficient, other amplifiers will probably
be less. 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 gauge wire.
Total RMS output x 2 = Total Input Wattage
Total Input Wattage = Current Draw (in Amps)
Supply Voltage
Example: A
POWERCLASS
™
4400 amplifier has four channels at 50 watts
RMS per channel into 4 Ohms (50 x 4 = 200). You would use the
formula in the following way:
200W x 2 = 400W
400W = 33.3A Total current draw.
12V
If the same amplifier is driven into a 2 Ohm stereo or 4 Ohm mono load,
double it's 4 Ohm RMS rating. All
POWERCLASS
™
amplifiers will effectively
double their power at this load.
100W x 4 x 2 = 800W
800W = 66.6A Total current draw.
12V
If you are using more than one amplifier, add up the total current draw
for all of them and choose the appropriate gauge based on the grand total.
P o w e r W i r e C a l c u l a t o r
Recommended MINIMUM Gauge
Total Current Draw
Length Of Wire To Be Run
( in Amps)
Up to 4ft. 4 to 7ft.
7 to 10ft. 10 to 13ft. 13 to 16ft. 16 to 19ft. 19 to 22ft. 22 to 28ft.
0-20
14
12
12
10
10
8
8
8
20-35
12
10
8
8
6
6
6
4
35-50
10
8
8
6
6
4
4
4
50-65
8
8
6
4
4
4
4
2
65-85
6
6
4
4
2
2
2
0
85-105
6
6
4
2
2
2
2
0
105-125
4
4
4
2
2
0
0
0
125-150
2
2
2
2
0
0
0 00
(
NOTE: The ground wire should be the same gauge as the power wire.
4
WIRING