Wiring Distance Chart

Wiring Distance (Measured in Feet)
6 Volt				Total Watts on Wire Run	12 Volt
12 Ga	10 Ga	8 Ga	6 Ga		12 Ga	10 Ga	8 Ga	6 Ga	4 Ga
89	141	225	357	6	356	566	900	1431	2276
66	106	168	268	8	267	424	675	1073	1707
59	94	150	238	9	237	377	600	954	1517
53	84	135	214	10	213	339	540	859	1366
44	70	112	178	12	178	283	450	715	1138
33	53	84	134	16	133	212	337	536	853
29	47	75	119	18	118	188	300	477	758
22	35	56	89	24	89	141	225	357	569
21	33	54	85	25	85	135	216	343	546
19	31	50	79	27	79	125	200	318	505
17	28	45	71	30	71	113	180	286	455
14	23	37	59	36	59	94	150	238	379
12	20	32	51	42	51	80	128	204	325
11	18	30	47	45	47	75	120	190	303
11	17	28	44	48	44	70	112	178	284
10	16	27	42	50	42	67	108	171	273
7	11	18	28	75	28	45	72	114	182
5	8	13	21	100	21	33	54	85	136
-	5	9	14	150	14	22	36	57	91
-	-	6	10	200	10	16	27	42	68
-	-	5	8	250	8	13	21	34	54
-	-	-	7	300	7	11	18	28	45

Wiring Distance (Measured in Feet)
6 Volt		Total Watts on Wire Run	12 Volt
12 Ga	89	6	12 Ga	356
10 Ga	141		10 Ga	566
8 Ga	225		8 Ga	900
6 Ga	357		6 Ga	1431
4 Ga	-		4 Ga	2276
12 Ga	66	8	12 Ga	267
10 Ga	106		10 Ga	424
8 Ga	168		8 Ga	675
6 Ga	268		6 Ga	1073
4 Ga	-		4 Ga	1707
12 Ga	59	9	12 Ga	237
10 Ga	94		10 Ga	377
8 Ga	150		8 Ga	600
6 Ga	238		6 Ga	954
4 Ga	-		4 Ga	1517
12 Ga	53	10	12 Ga	213
10 Ga	84		10 Ga	339
8 Ga	135		8 Ga	540
6 Ga	214		6 Ga	859
4 Ga	-		4 Ga	1366
12 Ga	44	12	12 Ga	178
10 Ga	70		10 Ga	283
8 Ga	112		8 Ga	450
6 Ga	178		6 Ga	715
4 Ga	-		4 Ga	1138
12 Ga	33	16	12 Ga	133
10 Ga	53		10 Ga	212
8 Ga	84		8 Ga	337
6 Ga	134		6 Ga	536
4 Ga	-		4 Ga	853
12 Ga	29	18	12 Ga	118
10 Ga	47		10 Ga	188
8 Ga	75		8 Ga	300
6 Ga	119		6 Ga	477
4 Ga	-		4 Ga	758
12 Ga	22	24	12 Ga	89
10 Ga	35		10 Ga	141
8 Ga	56		8 Ga	225
6 Ga	89		6 Ga	357
4 Ga	-		4 Ga	569
12 Ga	21	25	12 Ga	85
10 Ga	33		10 Ga	135
8 Ga	54		8 Ga	216
6 Ga	85		6 Ga	343
4 Ga	-		4 Ga	546
12 Ga	19	27	12 Ga	79
10 Ga	31		10 Ga	125
8 Ga	50		8 Ga	200
6 Ga	79		6 Ga	318
4 Ga	-		4 Ga	505
12 Ga	17	30	12 Ga	71
10 Ga	28		10 Ga	113
8 Ga	45		8 Ga	180
6 Ga	71		6 Ga	286
4 Ga	-		4 Ga	455
12 Ga	14	36	12 Ga	59
10 Ga	23		10 Ga	94
8 Ga	37		8 Ga	150
6 Ga	59		6 Ga	238
4 Ga	-		4 Ga	379
12 Ga	12	42	12 Ga	51
10 Ga	20		10 Ga	80
8 Ga	32		8 Ga	128
6 Ga	51		6 Ga	204
4 Ga	-		4 Ga	325
12 Ga	11	45	12 Ga	47
10 Ga	18		10 Ga	75
8 Ga	30		8 Ga	120
6 Ga	47		6 Ga	190
4 Ga	-		4 Ga	303
12 Ga	11	48	12 Ga	44
10 Ga	17		10 Ga	70
8 Ga	28		8 Ga	112
6 Ga	44		6 Ga	178
4 Ga	-		4 Ga	284
12 Ga	10	50	12 Ga	42
10 Ga	16		10 Ga	67
8 Ga	27		8 Ga	108
6 Ga	42		6 Ga	171
4 Ga	-		4 Ga	273
12 Ga	7	75	12 Ga	28
10 Ga	11		10 Ga	45
8 Ga	18		8 Ga	72
6 Ga	28		6 Ga	114
4 Ga	-		4 Ga	182
12 Ga	5	100	12 Ga	21
10 Ga	8		10 Ga	33
8 Ga	13		8 Ga	54
6 Ga	21		6 Ga	85
4 Ga	-		4 Ga	136
12 Ga	-	150	12 Ga	14
10 Ga	5		10 Ga	22
8 Ga	9		8 Ga	36
6 Ga	14		6 Ga	57
4 Ga	-		4 Ga	91
12 Ga	-	200	12 Ga	10
10 Ga	-		10 Ga	16
8 Ga	6		8 Ga	27
6 Ga	10		6 Ga	42
4 Ga	-		4 Ga	68
12 Ga	-	250	12 Ga	8
10 Ga	-		10 Ga	13
8 Ga	5		8 Ga	21
6 Ga	8		6 Ga	34
4 Ga	-		4 Ga	54
12 Ga	-	300	12 Ga	7
10 Ga	-		10 Ga	11
8 Ga	-		8 Ga	18
6 Ga	7		6 Ga	28
4 Ga	-		4 Ga	45

Maximum Voltage Drop 5%



Key to Longer Wire Runs

The Wiring Distance Chart gives the maximum length of a given remote lamp circuit, assume the entire remote load is concentrated at the end of the wire run.

If remote lamp fixtures are uniformly spaced along the circuit path (equal watts spaced at equal distance), the lengths in the table may be increased, based on the chart and formula below:

# of fixtures

2	3	4	5	6	N
1.33	1.5	1.6	1.67	1.71	2N/(N+1)

MULTIPLY FEET BY

For example, a 100-foot long, 12-volt, remote lamp circuit has four 12-watt fixtures spaced 25 feet apart. According to the Wire Distance Chart, #8 Ga. wire would be required for 48 total watts up to 112 feet, to allow a 5% voltage drop or less. However, since the fixtures are equal in wattage and are spaced equally along the circuit, the distance of 70 feet for #10 Ga. wire can be multiplied by 1.6 (70 x 1.6 = 112), so in this case up to a 112-foot wire run with #10 Ga. wire would be acceptable.
Note: For systems operating at less than 50 volts, the smallest permissible wire size is #12 Ga. copper or equivalent per NFPA70 (National Electrical Code), Article 720-4.