To protect the vessel and its crew from such contingencies, a “Reverse Polarity Warning”
light will illuminate when the connection turned on.
If the “Reverse Polarity” light should illuminate when connecting to
Shore Power, immediately disconnect the cable and contact the harbor
master advising him/her of the problem. Do not risk shock or system
damage!
4F7: AC Shore Power, Disconnecting & Connecting
The AC source selector breakers are used to determine the source of AC power for the
boat. Only one of these three breakers can be at one time. The breakers are “Shore Power A”
(forward shore power connectors) , “Shore Power B” (aft shore power connector) and “Ship
Power” (generator).
These switches should all be left “OFF” whenever you are connecting or disconnecting
the boat to shore. This is true so that you do not draw an arc from the plug due to the load of
the boat on the connector’s pins: such an arc will burn the contacts and eventually cause them
to overheat when in use, creating a fire hazard.
Once connected to shore power, monitor the AC voltmeter-ammeter to be sure you have
not overloaded the circuit.
Important Note: If the house/inverter batteries are low when you first
hook up to shore power, and the inverter is turned on (as it should be),
the inverter will begin charging its batteries at a very high charging rate,
drawing a lot of shore power current. Until this demand reduces (see
“The Inverter System” below), you should turn “OFF” other high-current
AC appliances such as the water heater.
You can then turn on AC appliances as needed. Watch the digital AC ammeter in the
“amps” mode to be sure you don't exceed the dock's available supply, typically 30 amps.
Here are some estimates of AC power consumption for typical appliances:
Water Heater
7.5 amps
Inverter
up to 22 amps
Hair Dryer
12 amps
TV
1.5 amps
Coffee maker
10 amps
Microwave/Convection
15 amps
Toaster
12 amps
Each cooktop burner
12 amps
Air Conditioning See 4.12
Section 4G: Electrical Systems, DC 4.14