Monaco SIGNATURE 2001 series, Owner'S Manual

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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 occur-
ring 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 discharged electrolyte will be capable of producing close to
the rated voltage, but only after a period of time has elapsed for enough of a
reaction to take place to bring the voltage back up. Hopefully, this explanation
will make clarify why a battery measured at rest can indicate 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 exponential. This is due to bat-
tery 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 (Ahrs) 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.
The working range of a deep cycle battery is between 50 and 100% state of
charge (SOC). Deep cycle batteries should not be cycled below 50% state of
charge. Discharging a deep cycle battery below 50% state of charge shortens
the life of the battery. Deep cycle batteries use an amp hour rating which is usu-
ally calculated over a 20 hour discharge interval. Example: A deep cycle battery
with a rated capacity of 100 Ahrs. is designed to release current at the rate of
five amps per hour. Multiply a 5 amp load over a 20 hour discharge period
equals the rated 100 Ahr. capacity. These discharge figures are calculated with
the battery starting at 100% state of charge with the battery at 80º Fahrenheit
when the discharge cycle begins. However, increasing the discharge load
applied to the battery from five amps to ten amps on a 100 Ahr battery does not
yield 10 hours of discharge time. This is due to the internal reactions which
occur when a battery is discharging. Actual discharge time for a 10 amp load
may be closer to eight hours of discharge time. Increasing the load applied to
the battery to 20 amps will not yield five hours discharge time but may be less
than three hours. It might be understood as a point of diminishing return.
Calculating applied loads to an inverter to approximate run time from the
battery amp hours available is not an equal trade up when voltage is inverted
and amperage is calculated. When the inverter is used to operate an AC load it
uses approximately ten times the DC current needed from the battery when
Electrical Systems - House
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S I G N A T U R E
8 • 2 1 7
Battery Charge Time
& Consumption Rate