Go here for
Print
Friendly Page
Electrical Systems
Electrical regulations and standards
that apply to boat builders and recreational boats.
ELECTRICAL TABLE:
33 CFR 183.425https://newboatbuilders.com/pages/33CFR_electrical.html
ALLOWABLE AMPERAGE OF CONDUCTORS FOR UNDER 50 VOLTS
The following table is used to calculate the appropriate wire size based on the temperature of
the insulation of the wire.
Note: This is the table that is in the Federal Regulations. ABYC Standard E-11 has
five separate tables based on how many conductors are in a wire bundle.
Table 1
- ALLOWABLE AMPERAGE OF CONDUCTORS FOR SYSTEMS UNDER 50 VOLTS |
Temperature Rating of Conductor Insulation
|
Conductor Size English (metric) |
60 C (149 F) |
75 C (167 F) |
80 C (176 F) |
90 C (194 F) |
105 C (221 F) |
125 C (257 F) |
200 C (392 F) |
Outside Engine space |
Inside Engine Space |
Outside Engine space |
Inside Engine Space |
Outside Engine space |
Inside Engine Space |
Outside Engine space |
Inside Engine Space |
Outside Engine space |
Inside Engine Space |
Outside Engine space |
Inside Engine Space |
Outside or Inside Engine Space |
18 (0.8) |
10 |
5.8 |
10 |
7.5 |
15 |
11.7 |
20 |
16.4 |
20 |
17.0 |
25 |
22.3 |
25 |
16 (1) |
15 |
8.7 |
15 |
11.3 |
20 |
15.6 |
25 |
20.5 |
25 |
21.3 |
30 |
25.7 |
35 |
14 (2) |
20 |
11.6 |
20 |
15.0 |
25 |
19.5 |
30 |
24.6 |
35 |
29.8 |
40 |
35.6 |
45 |
12 (3) |
25 |
14.5 |
25 |
18.8 |
35 |
27.3 |
40 |
32.8 |
45 |
38.3 |
50 |
44.5 |
55 |
10 (5) |
40 |
23.2 |
40 |
30.0 |
50 |
39.0 |
55 |
45.1 |
60 |
51.0 |
70 |
62.3 |
70 |
8 (8) |
55 |
31.9 |
65 |
48.8 |
70 |
54.6 |
70 |
57.4 |
80 |
68.0 |
90 |
80.1 |
100 |
6 (13) |
80 |
46.4 |
95 |
71.3 |
100 |
78.0 |
100 |
82.0 |
120 |
102 |
125 |
111 |
135 |
4 (19) |
105 |
60.9 |
125 |
93.8 |
130 |
101 |
135 |
110 |
160 |
136 |
170 |
151 |
180 |
2 (32) |
140 |
81.2 |
170 |
127 |
175 |
138 |
180 |
147 |
210 |
178 |
225 |
200 |
240 |
1 (40) |
165 |
95.7 |
195 |
146 |
210 |
163 |
210 |
172 |
245 |
208 |
265 |
235 |
280 |
0 (50) |
195 |
113 |
230 |
172 |
245 |
191 |
245 |
200 |
285 |
242 |
305 |
271 |
325 |
00 (62) |
225 |
130 |
265 |
198 |
285 |
222 |
285 |
233 |
330 |
280 |
355 |
316 |
370 |
000 (81) |
260 |
150 |
310 |
232 |
330 |
257 |
330 |
270 |
385 |
327 |
410 |
384 |
430 |
0000 (103) |
300 |
174 |
380 |
270 |
385 |
300 |
385 |
315 |
445 |
378 |
475 |
422 |
510 |
Notes for the above table |
Temperature Rating of Conductor Insulation |
|
60oC (140oF)
|
75oC (167oF)
|
80oC (176oF) |
90oC (194oF)
|
105oC(221oF)
|
125oC (257oF) |
200oC (392oF) |
1. See the
following table: Temperature Rating of conductor |
0.58 |
0.75 |
0.78 |
0.82 |
0.85 |
0.89 |
1.00 |
2. See the following Table: Number of current carrying conductors |
|
|
|
|
|
|
Correction Factor |
3 |
|
|
|
|
|
|
0.70 |
4 to 6 |
|
|
|
|
|
|
0.60 |
7 to 24 |
|
|
|
|
|
|
0.50 |
25 and above |
|
|
|
|
|
|
0.40 |
|
|
|
|
|
|
|
|
|