PLANNING THE INVERTER SYSTEM
Any large wattage inverter system requires planning before installation. There are several steps
to the planning process so the user must determine the following:
•
Maximum inverter wattage required
•
Operating time (run time) needed between battery recharges
•
Battery bank capacity in amp-hours
•
Charger requirement to charge batteries within a practical time
•
Distance between battery bank and inverter
DETERMINING MAXIMUM APPLIANCE WATTAGE
Do not exceed the watt maximum AC load or the inverter will shut down
Most electrical tools, appliances, and audio/video equipment have labels that list the unit's
power requirements in watts. If the tool or device is rated in amps, multiply the amps by 115
(115V AC) to determine the watts. For example, an appliance rated at 0.5 amps will draw 60
watts.
Remember to consider the startup surge that motorized appliances will cause. Do not exceed the
watt momentary surge rating of this inverter. This can cause immediate overload shut down and
or blow a fuse.
CONFIGURING THE BATTERY BANK
To determine the minimum battery ampere-hour rating that you will need to operate appliances
from the inverter and any DC appliances powered by the battery bank, follow these steps. The
following example applies to 12V systems only - for 24V or 48V systems, the same principles
apply, the actual calculation will vary depending on the inverter rated input voltage.
1. List the maximum continuous wattage that the inverter has to supply.
2. Estimate the number of hours the appliances will be in use between battery recharges.
This will vary depending on appliances. For example, a typical home-use coffee maker
draws 500 watts during its brew time of 5 minutes. It maintains the temperature of the pot,
requiring 100 watts. Typical use of a microwave oven is only for a few minutes. Some
longer operating time appliances are lamps, TVs, computers, and refrigerator/freezers.
Determine the total watt-hours of energy needed. This is done by multiplying average power
consumption in watts by hours of run time. For example: 500 watts for 10 hours = 5,000 watt
hours. To get an estimate of the maximum current (in amps) that a battery bank must be capable
of delivering to the inverter, divide the load watts by ten. For example a 500 watt appliance
load will need 50 amps at 12 volts DC. Using the 500 watts (or 50 amps) for 10 hours example
as above, then 50 amps is needed for 10 hours. This provides us with the basic amp-hours
(AH) of battery that is required. Ten hours at 50 amps equals 500 amp-hours (AH). There are
additional factors that determine actual run time. These include:
•
AC appliance load and time in use (basic AH).
•
Cable gauge and length (cable losses).
•
Charge level of the batteries (between use, chargers have to be able
to fully charge the batteries).
Wagan Tech and wagan.com are trademarks of Wagan Corporation.
User's Manual—Read before using this equipment
WATTS = VOLTS × AMPS
©2018 Wagan Corporation. All Rights Reserved.
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