Maintaining
the quality appearance and condition of your boat
Boat
Wiring and Color Codes
American Boat & Yacht Council Standards
for Boats
|
COLOR |
ITEM |
USE |
|
Black |
Ground |
Negative / Neutral
Main Return |
|
Blue-Stripe |
Tilt up and or trim out |
Tilt and or trim circuits |
|
Brown |
Alternator
Charge Light |
Generator
Terminal or Alternator Auxiliary Terminal to Regulator |
|
|
Generator
Armature |
Generator
Armature to Regulator |
|
|
Pumps |
Circuit
Breaker or Switch to Pumps |
|
Brown
w/Yellow |
Bilge
Blowers |
Circuit
Breaker or Switch to Blower |
|
Dark
Blue |
Cabin
& Instrument |
Circuit
Breaker or Switch to Lights |
|
Green
or |
Bonding
System |
Grounding
Wires (if insulated) |
|
Green
w/Yellow Stripe |
|
|
|
Green Stripe |
Tilt down and/or trim tab |
Tilt and or trim circuits |
|
Grey |
Navigation
Lights |
Circuit
Breaker or Switch to Lights |
|
|
Tachometer
|
Tachometer
Sender to Gauge |
|
Lt.
Blue |
Oil
Pressure |
Oil
Pressure Sender to Gauge |
|
Orange |
Accessory
Feed |
Ammeter
to Alternator or Generator |
|
|
Common
Feed |
Distribution
Panel to Accessory Switch |
|
|
Feed |
Accessory
Circuit Breakers or Switches |
|
Pink |
Fuel
Gauge |
Fuel
Gauge Sender to Gauge |
|
Purple |
Ignition |
Ignition
Switch to Coil & Electrical Instrument |
|
Red |
Power
Feeds |
Positive
Main Power (particularly un-fused) |
|
|
Instrument
Feed |
Distribution
Panel Electrical Instruments |
|
Tan |
Water temperature |
Water temperature sender to gauge |
|
Yellow |
Generator
Field |
Generator
to Regulator Field Terminal |
|
Yellow |
Ground |
Negative
/ Neutral Main Return |
|
Yellow
w/Red |
Starting
Circuit |
Starting
Switch to Solenoid |
Wire
/ Conductor Sizes
Length
(feet): Determined by measuring the
length of the wire from the positive (+) power source connection to the
electrical device and back to the negative (-) power source connection.
Note that the power source connection may be the battery, panel-board or
switchboard.
Current
(amps): Determined by adding the total
amps on a circuit.
Wire sizes not covered in Table C or Table D may
be calculated by using the following formula:
After calculating the Circular Mil Area (CM), use
Table B to determine the proper conductor size.
The National Fire Protection Agency and Coast Guard require that the next
larger conductor be used when the calculated CM area falls between two conductor
sizes.
CM=K x l x L / E
CM = Circular Mil area
of Conductors
K = 10.75 (Constant
representing the mil-foot resistance of copper)
I = Current - amps
L = Length - feet
E = Voltage drop at
load (in volts)
For Example:
Q. A bilge pump draws 10 amps.
The positive run is 11 feet from the power panel, including the float
switch. The negative run is only 10
feet. What size wire?
A.
Use the following formula to reach the correct answer:
CM
= 10.75 x 10 (amps) x 21 (total length of run) / 0.36 (3% of 12v) = 6,271
The
table below shows that 12 AWG wire has a CM area of 6,500 and is the correct
choice. However, SAE wire has a CM area of only 5,833.
Under NFPA and USCG regulations, 10 SAE wire must be used.
CM = 10.75 x 10 (amps) x
21 (total length of run) / 0.96 (3% of 32v) = 2,352
Ampacity is the ultimate safe current carrying
capacity of the wire before damage occurs to the insulation, without regard to
voltage drop. Because the
insulation of most SAE wire types is not the same as ANCOR, this chart should
not be used for other conductor types.
|
AWG |
Sq. |
AWG |
SAE |
Ampacity |
Ampacity |
|
18 |
0.8 |
1,600 |
1,537 |
20 |
17 |
|
16 |
1 |
2,600 |
2,336 |
25 |
21 |
|
14 |
2 |
4,100 |
3,702 |
35 |
30 |
|
12 |
3 |
6,500 |
5,833 |
45 |
38 |
|
10 |
5 |
10,500 |
9,343 |
60 |
51 |
|
8 |
8 |
16,800 |
14,810 |
80 |
68 |
|
6 |
13 |
26,600 |
24,538 |
120 |
102 |
|
4 |
19 |
42,000 |
37,360 |
160 |
130 |
|
2 |
32 |
66,500 |
62,450 |
210 |
178 |
|
1 |
40 |
83,690 |
77,790 |
245 |
208 |
|
1/0 |
50 |
105,600 |
98,980 |
285 |
242 |
|
2/0 |
62 |
133,100 |
125,100 |
330 |
280 |
|
3/0 |
81 |
167,800 |
158,600 |
385 |
327 |
|
4/0 |
103 |
211,600 |
205,500 |
445 |
378 |