(Continued from Part 2. This concludes the article.)
Inverters
Most of us are interested in running a few 120 volt AC appliances. The fridge, the furnace, the shallow well pump – standard AC devices that we want to keep alive during a power outage. For these we will require what is known as an inverter. Inverters take DC battery power and invert it into standard 120 volt AC household power.
Inverters are available in all shapes and sizes these days. You can get off-shore-manufactured modified sine wave inverters that plug into the cigarette lighter plug in your car, rather cheaply. These might even be enough to charge your phone, or laptop computer. The rule of thumb is that these devices produce about half of what they consume. For example, if your cigarette lighter plug is fused at 15 amps at 12 volts DC, the inverter can be expected to produce a little less than 1 amp at 120 volts AC.
If you want to run other appliances, you will need a far more robust inverter. Cheap Chinese-made inverters rated at 2000 watts can be had these days for under $1,000 – sometimes far less than that. These might mostly work at the stated spec, but read the fine print before you decide to buy. And keep in mind that they are often rated for momentary maximum draw, not continuous draw. That 2000 watts stated capability might realistically be less than 1500 watts, continuous. Momentary draw duration also tends to vary, by manufacturer. For some manufacturers, momentary might refer to 15 seconds. To others momentary might be based on 15 minutes. You do tend to get what you pay for.Continue reading“Weather the Storm with Backup Power – Part 3, by E.R.”