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Proper wire size is absolutely critical to insure that your heater works properly. Undersized wire is the single biggest mistake made when installing our heaters. To function properly, these heaters must be wired with the proper size wire, and  grounded properly, this cannot be stressed enough.

Battery performance is dramatically reduced in low temperatures as well.  A battery  that is required to operate continuously at 0 degrees F will provide about 60% of its capacity.

 Wire size in Direct Current is VERY important.  In low voltage systems (12, 24, 36 and 48VDC) the overriding concern is power loss. Wire must not be sized merely for the ampacity, because there is less tolerance for voltage drop (except for very short runs). For example, a 1V drop from 12V causes 10 times the power loss of 1V drop from 120V. See the chart below to determine the maximum run with each gauge wire at a specific voltage.

 The numbers represent the maximum number of feet that wire can be ran without exceeding a 2 % loss. An example would be: A 12 volt heater, pulling 40 Amps, using a 10 gauge wire, could be ran a maximum of 2.8 feet. You can go twice the distance where a 4% loss is acceptable. A 4% loss however is not recommended by DC Thermal and will result in less than desirable results with our heaters.

 

To purchase GHL Hook up Wire, Click HERE. 

12 Volt 2% Wire Loss Chart

AMPS

14 ga.

12 ga.

10 ga.

8 ga.

6 ga.

4 ga.

2 ga.

1/0 ga.

1

45

70

115

180

290

456

720

2

22.5

35

57.5

90

145

228

360

580

4

10

17.5

27.5

45

72.5

114

180

290

6

7.5

12

17.5

30

47.5

75

120

193

8

5.5

8.5

15

22.5

35.5

57

90

145

10

4.5

7

12

18

28.5

45.5

72.5

115

15

3

4.5

7

12

19

30

48

76.5

20

2

3.5

5.5

9

14.5

22.5

36

57.5

25

1.8

2.8

4.5

7

11.5

18

29

46

30

1.5

2.4

3.5

6

9.5

15

24

38.5

40

2.8

4.5

7.0

6.5

18

29

50

2.3

3.6

5.5

9

14.5

23

 

24 Volt 2% Wire Loss Chart

AMPS

14 ga.

12 ga.

10 ga.

8 ga.

6 ga.

4 ga.

2 ga.

1/0 ga.

1

90

140

230

360

580

912

1440

2

45

70

115

180

290

456

720

1160

4

20

35

55

90

145

228

360

580

6

15

24

35

60

95

150

240

386

8

11

17

30

45

71

114

180

290

10

9

14

24

36

57

91

145

230

15

6

9

14

24

38

60

96

153

20

4

7

11

18

29

45

72

115

25

3.6

5.6

9

14

23

36

58

92

30

3

4.8

7

12

19

30

48

77

40

5.6

9

14

23

36

58

50

4.6

7.2

11

18

29

46

 

36 Volt 2% Wire Loss Chart

AMPS

14 ga.

12 ga.

10 ga.

8 ga.

6 ga.

4 ga.

2 ga.

1/0 ga.

1

135

210

345

540

870

1368

2160

2

67.5

105

172.5

270

435

684

1080

1740

4

30

52.5

82.5

135

217.5

342

540

1160

6

22.5

36

52.5

90

142.5

225

360

579

8

16.5

25.5

45

67.5

106.5

171

270

435

10

13.5

21

36

54

85.5

136.5

217.5

345

15

9

13.5

21

36

57

90

144

229.5

20

6

14

16.5

27

43.5

67.5

108

172.5

25

7.2

11.2

18

28

46

72

116

184

30

4.5

7.2

10.5

18

28.5

45

72

115.5

40

11.2

18

28

46

72

116

50

9.2

14.4

22

36

58

92

 

 48 Volt 2% Wire Loss Chart

AMPS

14 ga.

12 ga.

10 ga.

8 ga.

6 ga.

4 ga.

2 ga.

1/0 ga.

1

180

280

460

720

1160

1824

2880

2

90

140

230

360

580

912

1440

2320

4

40

70

110

180

290

456

720

1160

6

30

48

70

120

190

300

480

772

8

22

34

60

90

142

228

360

580

10

18

28

48

72

114

182

290

460

15

12

18

28

48

76

120

192

306

20

8

14

22

36

58

90

144

230

25

7.2

11.2

18

28

46

72

116

184

30

6

9.6

14

24

38

60

96

154

40

11.2

18

28

46

72

116

50

9.2

14.4

22

36

58

92

 

 72 Volt 2% Wire Loss Chart

AMPS

14 ga.

12 ga.

10 ga.

8 ga.

6 ga.

4 ga.

2 ga.

1/0 ga.

1

270

420

690

1080

1740

2736

4320

2

135

210

345

360

580

912

1440

3480

4

60

105

165

270

426

684

1080

1740

6

45

72

105

180

285

450

720

1158

8

33

51

90

135

213

342

540

870

10

27

42

72

108

171

217

435

690

15

18

27

42

72

114

180

288

489

20

12

21

33

54

87

135

216

345

25

10.8

16.8

27

42

69

108

174

276

30

9

14.4

21

36

57

90

144

231

40

16.8

27

42

69

108

174

50

13.8

21.6

33

54

87

138