Operating instructions

Newmar charger in starboard side of engine
room.,
The E/R boxes holding some of the
batteries are visible in this picture to port of
the port engine.
Notice the batteries in each lower corner of
the 20kw generator area: These are the
starting batteries for each generator.
Red arrow points to McCarron charger;
yellow arrow points to the Trace Inverter.
4G2: DC Batteries
The batteries on this boat are not just one, big all-purpose
battery. To have redundancy, there are actually several “banks”
of batteries assigned different tasks.
A “starting bank” is used for starting engines. This battery
is charged by the engine alternator when running, or by the
McCarron battery charger if it is on when there is shore power or
a generator is running.
Another “house bank” consists of deep cycle batteries
wired in parallel. These batteries are charged by the engine
alternators and by the Inverter when AC power is present from
shore power or a generator.
In the event of a low engine-starting bank, the operator
can (1) start a generator which can then run the chargers or (2)
operate the battery-parallel switch (see below).
Note: If it takes more than two attempts to start
any engine, turn off its sea water valve to avoid
water-locking the engine until it starts. Then be
sure to immediately turn it back on after the
engine is started!
Two more smaller batteries start each generator. Each of
these is charged by the generator to which it is connected, and
by the Newmar charger.
What redundancy!
4G3: DC Battery Chargers
The vessel is equipped with two 12-volt battery chargers.
One of these, a Newmar unit, charges the two genset batteries.
The other, McCarron charger, charges the starting battery.
The Inverter is also a 12-volt charger. It charges the
house battery bank.
The chargers are switched on by breakers in the 120-volt
circuit breaker panel.
Only the Inverter charger is normally used!
Note: The Inverter is primarily used for house
battery charging; see discussion about the
inverter below!
Section 4G: Electrical Systems, DC 4.15