battery to mains power (12v to 110v)?

Question

if i have an apliance that uses main power at 8Amps and i want to use a 12 V battery (truck or car ect...)and a transformer to make it 110v how long will the battery last ?

Answer 1

First, a transformer will not work for DC. What you need is an inverter to change from DC to AC it will step up the voltage to 120V. How long depends on the battery. 8 amps at 110V is 880 watts. it will take about 80 amps from the battery to supply the same power plus a little more for inefficiency of the inverter. A very large car battery might be good for 6-8 hours but the voltage will keep dropping and my get too low for whatever your device is sooner than that.