Monaco LaPalma, Owner'S Manual

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Electrical Systems 2004 • LaPalma
operated at or below its 15 GPM level, it will hold 12 psi. However, a pump
that is connected to a water tank with a finite capacity will start to lose the
ability to hold pressure as the level of water in the tank drops. Think of
siphoning water from a bucket. As the level of the water drops the volume of
water exiting the siphon slows down.
When the tank is full it is capable of feeding more “pressure” to the
pump inlet due to gravity, and the pump always has enough water available
to maintain its rated pressure and volume. However, if the water tank gets
low the pump will not have enough water volume coming in to maintain 12
psi at 15 GPM. If the loads are taken away from the pump by closing the
valve on the outflow, even with low pressure in the tank the pump will
eventually pump up to 12 psi. It will just take it longer to get there. When
the valve is opened the pump will sustain 12 psi for a brief period, but since
the tank is no longer feeding the pump as fast as needed the pressure will
eventually drop. This analogy can be restated by replacing the pump with a
battery, pressure with voltage, volume with amps, outflow valve with a
switch, water with electricity and the water tank with the battery electrolyte.
The level of the tank could be thought of as the rate of the reaction taking
place in the electrolyte. When the battery is fully charged the electrolyte has
an excess of reactions taking place to feed the battery terminals. This tapers
off with time as the electrolyte is spent so maintaining voltage becomes
possible. With no loads the spent electrolyte will be capable of producing
close to the rated voltage, but only after a period of time has elapsed for
enough reactions to take place to bring the voltage back up. Hopefully, this
scenario will help make clear why a battery measured at rest can show close
to its rated voltage but will not run a load.
Calculating Run Times:
Calculating run time figures when operating 120 Volt AC electrical items
with an inverter can be expediential. This is due to battery characteristics.
Flow characteristics of electrons vary with different battery types and
chemical compositions. Deep cycle batteries are generally designed to
slowly release a majority of their charge capacity. Deep cycle batteries are
rated in amp hours (Ahr) with the discharge occurring over an extended
period of time before the battery is charged. Engine starting batteries are
designed to quickly release large amounts of current for short durations
without depleting battery reserves. Commercial type batteries bridge the gap
of deep cycle and engine batteries. Commercial batteries release medium
amounts of current over a longer period of time, but they are not designed to
cycle their charge capacity.
Battery Charge
Time &
Consumption Rate