Recommended minimum gauge – Precision Power PCX 250 User Manual
Page 10
The following is a basic formula to be used as a guide to determine current draw.
A50% amplifier efficiency rating is used as an average. Your new
P C X™
a m p l i f i e r
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 gauge wire.
Total Amplifier RMS output x 2 = Total Input Wattage from car
Total Input Wattage = Current Draw (in Amps)
Supply Voltage
Example: A
POWERCLASS™ PCX 280
amplifier has two channels at 80w per
channel RMS rating into 4 Ohms (80 x 2 = 160).
You would use the formula in the following way:
160W x 2 = 320W
320W = 26.6 Amps 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.
160W x 2 x 2 = 640W
640W = 53.3 Amps 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.
NOTE: The ground wire must be the same gauge or larger as the power wire.
Recommended Minimum Gauge
(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.
25-50
10
10
8
8
6
6
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
150-200
0
0
0
0
00
00
00
000
200-250
00
00
00
000
000
000
000
0000
Total Current Draw
Length Of Wire To Be Run
17