Xantrex Technology 3000 - Manual (Page 49)

Estimating Battery Requirements
975-0128-01-01 B–3
This same battery can deliver a higher or lower current for less or more
time, limited approximately by the 100 Ah figure (for example, 50 A for 2
hours, or 200 A for 1/2 hour), but usually the capacity figure given is only
accurate at the specified rate (20 hours).
To calculate the battery capacity you require, read “Estimating Battery
Requirements” on page B–3 and “Battery Sizing Example” on page B–4,
and then complete the “Battery Sizing Worksheet” on page B–5.
Estimating Battery Requirements
To determine how much battery capacity you need:
1. Determine how many watts are consumed by each appliance that you
will operate from the XPower 3000. You can normally find the watt
rating labelled on the product. If only the current draw is given,
multiply it by 115 to get the power consumption in watts.
2. Estimate how many hours each appliance will be operating each day.
3. Calculate the daily watt-hours needed for each appliance.
4. Add the total number of watt-hours needed for all the appliances and
multiply it by the number of days between charges.
5. Divide the total watt-hours of AC load between charges by 10. This
gives the battery Ah used between charges.
6. Double the total Ah used between charges to get the recommended
battery size in Ah.
See the battery sizing example that follows.
XPower3000.book Page 3 Wednesday, December 10, 2003 6:52 AM