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Old 08-04-2014, 09:17 AM   #30 (permalink)
BobS
diesel doer
 
Join Date: Oct 2013
Location: Gainesville, FL
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All laptops and DVD players work on 12 volts DC (and 5 volts, generated internally). All laptops have an external box (transformer) on the power line to the device. On it, you will find a number for either amps or watts, usually amps. If in watts, divide by 2 t(if in amps, multiply 1/2 the amps times the volts given) to get a generous typical usage figure. Note that adding a DC to AC converter then plugging in the AC to DC transformer box is adding unnecessary circuitry and power usage.
So, charge the battery on your non-gaimng computer, take it and the USB sticks and as backup, a good book and see how long the battery lasts. If it lasts all nite, then your problem is solved. If it doesn't, then take the number of hours it did not last and multiply that times the typical usage wattage figure you calculated above. That will be all that you need to cover the 8 hour shift. If your computer battery lasts over 4 hours, you can then run a line to your car and use the car battery to power the set since 4 hours of low wattage usage will leave plenty of juice for starting the car. Just use lamp cord wire to the car as it is cheap and keeps the resistance to current flow low. Don't take my word for it, test it. Run the computer on it's fully charged battery and see how long it lasts and then subtract that time from 8 hours and then run the computer on the car battery for the remaining hours on your day off and verify that it works. If this saves you a great amount of money, I accept donations.
Bob
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