inverter question and setup
before i start i know that ideally i should be using the carnetix p1900 or 2140 but right now that is outside my budget area.
i plan on using a laptop as my setup and i found a 800w inverter on craigslist for $30. from what i have read using an inverter will not be able to survive crank for no more then a few months. also if that if the laptop is on when i turn on my car that it will force my laptop to restart. what i have been thinking about in doing is either putting in a manual switch to control the inverter to turn on only when i want or to build a relay that would be able to delay the inverter from turning on when the car is started up.
the first setup would be that i would power the laptop off of its own battery, when the battery is low i would flip the switch on to turn on the inverter to charge and run the laptop. i would also have to build something in between the ignition and switch so that the inverter would turn off when i would turn the car off.
the second setup i was thinking about would be trying to build a relay that wait a minute or so before it turns on and starts powering the laptop. the laptop would already be on and running before the inverter turns on.
does it matter if the laptop is on before the inverter turns on?
i have been also considering just building a dc dc regulator but i am not that confident yet in my soldering skills to take on that task.