SAMS Vessel Electrical Systems 2

Question 1

According to ABYC E-11, what is the maximum allowable voltage drop for a vessel's DC lighting circuit?

Accepted Answer

3%

Answer

5%

Answer

10%

Answer

2%

Question 2

A marine surveyor finds bare copper conductors used throughout a vessel's bilge wiring. This is a concern primarily because:

Accepted Answer

Bare copper corrodes rapidly in the marine environment and may cause high-resistance connections

Answer

Bare copper is prohibited by USCG regulations in all bilge areas

Answer

Copper conductors are not approved for DC systems below 50V

Answer

Bare copper has insufficient ampacity for bilge pump loads

Question 3

Which type of battery is most commonly recommended for dual-battery systems on recreational vessels due to its tolerance for deep discharge?

Accepted Answer

Deep-cycle battery

Answer

Starting (cranking) battery

Answer

Absorbed Glass Mat (AGM) starting battery

Answer

Gel-cell starting battery

Question 4

When inspecting shore power connections on a vessel, a surveyor should verify that the shore power cord receptacle is rated for:

Accepted Answer

At least 125% of the maximum load current

Answer

Exactly the same amperage as the main breaker

Answer

No more than 80% of the shore power panel ampacity

Answer

The same voltage as the vessel's inverter output

Question 5

On a vessel with a 12V DC system, a surveyor measures 0.5V drop across a battery switch under load. This indicates:

Accepted Answer

Excessive resistance likely due to a corroded or loose switch contact

Answer

A normal reading within acceptable limits

Answer

The switch is rated for AC current only

Answer

The battery is fully charged and the switch is functioning correctly

Question 6

A vessel's engine compartment contains fuel tanks and an AC inverter. The inverter installation must:

Accepted Answer

Be ignition-protected to prevent sparks that could ignite fuel vapors

Answer

Be installed above the waterline only

Answer

Use only 240V output to reduce current and spark risk

Answer

Be disconnected when the engine is running

Question 7

Which NFPA/ABYC standard governs the installation of electrical systems on recreational boats in the United States?

Accepted Answer

ABYC E-11

Answer

NFPA 303

Answer

USCG 33 CFR Part 183

Answer

ISO 13297