Size Wire and Over Current Protection

Question 1

INDUSTRY STANDARD FOR APPLIED

Answer 1

ABYC is our most important standard for boats less than 100ft and depending on the specifications of each vessel

Question 2

Appropriate accommodations for conductors going through an engine room

Answer 2

adjust wire sizing due to reduced amount of current we can safely pass through

Question 3

AWG

Answer 3

American Wire Gauge

Question 4

Voltage Drop Requirements

Answer 4

3% allowable voltage drop for important devices

10% for more leisurely devices

Question 5

What do you need to do to determine OCPD size?

Answer 5

1. check the chart based on conductor size
2. must be equal or less than 150% of ampicity of conductor
3. If a motor, follow manual to prevent rotor lock

Question 6

When are OCPD’s required to be ignition protected?

Answer 6

1. Anywhere there is gas

2. In the engine room

Question 7

7-40-72” rule

Answer 7

Must have an OCPD within 7” from the power source unless directly attached to the battery the conductor is directly attached to battery and sheathed, in which it can be 72”. coming from a secondary power source AND SHEATHED it can be up to 40”

Question 8

what do we use the AIC chart to determine and why?

Answer 8

determine what type of OCPD to use in the event of a dead short based on the battery bank’s CCA, MCA, or rated capacity.

Question 9

What does AIC stand for and what does it mean?

Answer 9

Ampere Interrupting Capacity. It is the maximum current an OCPD can stop before a creating an arc.