64
Speci
fi
cations
2% Voltage Drop Charts for 75°C Stranded Copper Wire
1-Way Wire Distance (feet), 12 Volt System
Wire Size
(AWG)
60
Amps
55
Amps
50
Amps
45
Amps
40
Amps
35
Amps
30
Amps
25
Amps
20
Amps
15
Amps
2/0 **
22.4
24.4
26.9
29.9
33.6
38.4
44.8
53.8
67.2
89.6
1/0 **
17.8
19.4
21.3
23.7
26.6
30.4
35.5
42.6
53.3
71.0
2
11.2
12.2
13.4
14.9
16.8
19.1
22.3
26.8
33.5
44.7
4
7.0
7.7
8.4
9.4
10.6
12.1
14.1
16.9
21.1
28.1
6
4.4
4.8
5.3
5.9
6.6
7.6
8.8
10.6
13.2
17.7
8
2.8
3.0
3.3
3.7
4.2
4.8
5.6
6.7
8.4
11.1
10
1.7
1.9
2.1
2.3
2.6
3.0
3.5
4.2
5.2
7.0
12
1.1
1.2
1.3
1.5
1.6
1.9
2.2
2.6
3.3
4.4
14
0.7
0.8
0.8
0.9
1.0
1.2
1.4
1.7
2.1
2.8
Table 8-1. Maximum 1-way wire distance for 12 Volt systems, stranded copper, 2% voltage drop
1-Way Wire Distance (meters), 12 Volt System
Wire Size
(mm
2
)
60
Amps
55
Amps
50
Amps
45
Amps
40
Amps
35
Amps
30
Amps
25
Amps
20
Amps
15
Amps
70 **
6.83
7.45
8.20
9.11
10.24
11.71
13.66
16.39
20.49
27.32
50 **
5.41
5.91
6.50
7.22
8.12
9.28
10.83
12.99
16.24
21.65
35
3.40
3.71
4.08
4.54
5.11
5.84
6.81
8.17
10.21
13.62
25
2.14
2.34
2.57
2.86
3.22
3.68
4.29
5.15
6.43
8.58
16
1.35
1.47
1.61
1.79
2.02
2.31
2.69
3.23
4.04
5.38
10
0.85
0.93
1.02
1.13
1.27
1.46
1.70
2.04
2.55
3.40
6
0.53
0.58
0.64
0.71
0.80
0.91
1.07
1.28
1.60
2.13
4
0.33
0.36
0.40
0.44
0.50
0.57
0.67
0.80
1.00
1.33
2.5
0.21
0.23
0.25
0.28
0.32
0.36
0.42
0.50
0.63
0.84
Table 8-2. Maximum 1-way wire distance for 12 Volt systems, solid copper, 2% voltage drop
** Wires sizes larger than 2 AWG (35 mm
2
) must be terminated at a splicer block located outside of the TriStar MPPT wiring box.
Use 2 AWG (35 mm
2
) or smaller wire to connect to the TriStar MPPT to the splicer block.
Notes:
• The speci
fi
ed wire length is for a pair of conductors from the solar or battery source to the
controller (1-way distance)
• For 24 volt systems, multiply the 1-way length in the table by 2.
• For 48 volt systems, multiply the 1-way length in the table by 4.
• Shaded cells in the table indicate that the current exceeds the ampacity of the wire for a
given ambient temperature as de
fi
ned in the following table:
Wire Ampacity* Key
Exceeds wire ampacity at 60°C ambient temperature
Exceeds wire ampacity at 50°C ambient temperature
Exceeds wire ampacity at 40°C ambient temperature
Exceeds wire ampacity at 30°C ambient temperature
*Ampacity for not more than three current-car-
rying conductors in a raceway, cable, or earth
(buried).
