Pure Line 3000 by Wagan Tech
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Cable gauge and length (cable losses).
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Charge level of the batteries (between use, chargers have to be able
to fully charge the batteries).
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Temperature of the batteries (colder batteries provide fewer amps).
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Age and condition of the batteries (older batteries lose AH capacity).
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Compliance with turning off unnecessary AC loads.
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Use of DC appliances and compliance with turning off unnecessary
DC loads.
DERATING THE BATTERY BANK
Most lead-acid batteries have a rating expressed in amp-hours (AH). The most
common rating of AH is "at the 20 hour rate".
NOTE: Despite several internet explanations, there is no relationship between
cold cranking amps (CCA) and ampere-hours (AH).
For example, if a 20 AH battery is discharged at a 1 amp rate, is will take 20
hours to discharge that battery. The terms "charged" and "discharged" relate to
actual battery voltage. This means that the output voltage of a nominal 12 volt
battery starts at 13.4 volts (fully charged) then drops to 10.7 volts (discharged).
If the load on the battery causes the battery to discharge faster than the 20
hour rate, the capacity (AH) of the battery is measurably reduced (derated). In
heavy battery discharge applications, double the estimated Amp Hour rating
and configure batteries to support this capacity. If the batteries are frequently
charged by an alternator, the Amp Hour rating of the battery may be reduced.
SETTING UP THE BATTERY BANK
Batteries that are used indoors or inside a vehicle or vessel, should be deep-
cycle, sealed lead acid batteries.
NOTE: It is important that for any inverter installation to battery protection fuses.
Battery fuses are added to the positive (+) battery cable as close as possible to
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