Airstream 360 XL, Owner'S Manual

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AIRSTREAM 390/396 XL
ESTIMATING YOUR OPERATING TIMES
With your Airstream inverter installation using two 4-D batteries (your XL has 4) in good condition and
fully charged you will find that the total capacity (running times) will depend on the total wattage load of
the devices you are powering. In general, the running time is proportionate to the wattage.
Using the following tables, you can estimate which combinations of appliances you may operate. Table 1
indicates the typical wattage of various appliances.
*Largest bank of incandescent light bulbs that the inverter can start simultaneously and operate for at least
one minute.
Notes: If the current draw at 120 VAC is known, then the battery amperage at 12VDC will be 10
times the AC amperage divided by the efficiency (90% in this table).
Motors are normally marked with their running rather than their starting current. Starting current
can be five times running current.
*Refrigerators and icemakers typically run about 1/3 of the time. Therefore, their average battery
current draw is 1/3 what their amp rating would indicate.
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