Monaco 2008 Knight, Owner'S Manual

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166
2008 knight
elecTrical sysTems - house — 8
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 usually calculated over
a 20 hour discharge interval.
For example:
A
deep cycle battery with a rated capacity of 100
Ahrs. is designed to release current at the rate
of 5 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 F when
the discharge cycle begins. However, increasing
the discharge load applied to the battery from
5 Amps to 10 Amps on a 100 Ahr battery does
not yield ten 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 inverting 12 Volts
DC to operate the 120 Volt AC item. There is
also a small efficiency loss of about 10% when
inverting.
For example: When using the inverter
to operate an AC electrical item, which has a
current draw rating of 2 Amps, the inverter will
use over 20 Amps DC power from the batteries.
Determining Current Consumption:
First determine the amount of current used
by an AC item.
For example: The television is
rated at 200 watts at 120 Volts AC. Calculate
watts to amps. Divide 200 watts by the operating
voltage of 120, this equals 1.6 Amps. Multiply
1.6 Amps AC current by a factor of ten the
inverter will use, this equals 16 Amps DC
battery current. Add the revised 10% efficiency
loss figure, this calculates to a total of 17.6
Amps DC. If the battery bank capacity is rated at
500 Ahrs., actual elapsed time to the suggested
50% state of charge would net viewing time for
the television at approximately 13 hours in ideal
conditions.
The run time figure will vary greatly with
the actual state of charge of the battery bank
when the discharge process begins. Ambient
temperature, combined with other working
loads, such as lights and parasitic loads applied
to batteries, affect run times. Calculating the
exact run time is not precise due to all the
variables and equations involved; however,
an approximate time figure can be obtained.
Proper battery maintenance and charge cycles
affect battery performance. Observe the battery
condition with hydrometer and voltage readings.
Use only distilled water when filling batteries.
To achieve the highest quality of battery
performance and longevity maintain the batteries
in their proper operating range.
lIgHtS
Incandescent Light
The bulb inside the 12V incandescent light is
replaceable.
To Replace a Bulb:
1. Carefully squeeze the lens cover then
gently pull the cover out. The cover has
tabs that lock the cover in place
2. Using a clean cloth or piece of tissue
carefully grasp the bulb and rotate to
the unlock position.
3. Remove bulb from the socket.
4. The bulb replacement is 1141 12V
21CP.
NOTE
Replacement bulb number is accurate at
time of printing. Confirm replacement
bulb number before ordering or
obtaining a replacement.
5. Using a clean cloth or piece of tissue
grasp the new bulb and align the
prongs on the bulb with the slot on
light socket.
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