Monaco DIPLOMAT 2004, Руководство пользователя

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ELECTRICAL SYSTEMS - HOUSE
DIPLOMAT 2004
period equals the rated 100 Ahr. capacity. These discharge figures are calcu-
lated 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 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 inverting 12 Volts to operate the 120 Volt 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. 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 fig-
ure, 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, com-
bined 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 keep batteries in
their proper operating range.