Thread: confused about power options

so could the inverter potentially damage the computer?

Originally Posted by Bugbyte

The opus has auto startup and shutdown capabilities. It has a power regulator built in. It survives crank. Inverters are notorious for introducing noise -usually alternator whine, into the system.

I have put my Car Computer project on hold because of power supply issues.

The 150W Opus might fall short of the power I need. I really want to stick with Opus - I read somewhere that there might be an Opus 250Watt (even 200 watts will do me fine) coming out.

How true is this? Does anyone have any dates?

Any alternatives to the Opus that are just as good but 200Watts?

Yeah there are beefier dc-dc power supplies, but the opus holds the same advantage over them that it holds over inverters - it includes startup/shutdown capabilities. Most other advantages of dc-dc over inverters are just myths, noise and safety issues included. I'm not sure how much longer we're going to have to wait for a better dc-dc option. I've heard that there's another member here designing his own dc-dc psu, and I know that I'll be resuming mine when I get my hands on a scope. Somebody should have one any minute now. This waiting is silly. It's not like it's breakthrough technology...

If you'd rather use an inverter for the time being, don't be afraid. If you have any noise issues, it's because you've wired something wrong. You won't be bothered a bit by the inefficiency unless you need every last second of run time with the engine off. Many inverters will survive crank, but it just depends on the inverter's specs, and the size of your engine, starter, and battery. I've seen the same inverter survive crank in a civic but not a 240. I'm using an inverter setup right now until my dc-dc psu is ready, and I find the most annoying part to be the lack of startup/shutdown control, and the size of everything. I could use an independent startup/shutdown controller and add a relay to turn on/off the inverter to take care of that issue, but I won't bother as this is temporary. The size issue does bother me, though. Even after gutting it, the atx psu makes the dimensions of my computer case a few cm bigger, and I've got the separate inverter to deal with.

hmm i think i'll spend a few extra bucks on an opus then, i'll try to find one used.

another question- can you have a dedicated car battery (or two :-)) just for your opus? For example, you'd have your real car battery under da hood, and two more in the trunk just for your computer. That way, you could use your computer when your car was off. Btw, how much run time can you get off a full car battery while you're using your carputer?

Also, how would you wire the batteries up so that the rear ones would get charged?

thanks alot

I am not sure about run time but do a for tank circuit here and on and you will see how to hook it up

ok got it, but i still have one more question- how long can the average carputer with a touchscreen last on a fully charged car battery?