Running more than 150 watts of stuff through vehicle dc port?

[Veraster]

I don't know if this is the right sub forum to post in but this is my best guess.

So I recently ordered an Alienware m14x laptop. The charger it comes with is a huge and almost ridiculous 150 watt charger. I am planning on going on a 2 day road trip in the next month or two.

The dc power port on the vehicle I will be in has a sticker on all three of it's ports saying the maximum total power on all ports must not exceed 120 watts. Attached is a picture.

I have had a 90 watt laptop powered by a 100 watt power inverter plus a gps and two dvd players plugged in the other outlets at the same time without problems. So the total of the 100watt inverter plus all that other stuff was probably really close to that limit. I don't know how close.

So if I plugged in a power inverter capable of running my alienware laptop plus all that other stuff, what would happen? Would it blow a fuse? Would the alternator not be able to keep up? What would happen?

[94lt1]

Its a recommendation, you take a chance on over loading your alternator or blowing a fuse.. I wouldn't recommend it myself....that's just me though...

You have larger fuses under your hood as well as the fuses in the fuse boxes.... and often times when it comes to an electric overload or short, its one of those that blows...

[LoudRam]

You also run the risk of melting your wires and/or connections. Car fires are not pretty.

[lloydstrans]

my M18X R2 power brick is quite a bit bigger than yours will be, the cable has a sticker saying its rated for 10 amps (240 watt). So even if it draws 5 amps that is still quite a lot, not for the alternator, but for the wiring system. A hard wired power converter is the best bet if you can't stand driving and not playing BF3 at the same time. Take loudrams parting comment to heart. YOU ARE BEING WARNED. I hope your not a person trolling for the the one reply that says "go for it"!!!!!!! ALIENWARE ROCKS

[Xfactorx316]

Whether you decide to risk it or not is up to you, but the one thing I strongly discourage you from trying is just putting in a bigger fuse.... That is when wires do melt and fires can happen. Ideally if the draw is too much it should pop the fuse first. I used to install Moible Audio/electronics and Security and one of the most common problems we'd come across is people discovering that it was only a 5 or 10 amp fuse and trying to put a bigger fuse and then melting wires..... In this case the manufacturers recommendations are a really good thing to go by!

[Veraster]

OK thanks. I'll just wire it directly to the battery. I haven't looked at it yet but is there room to easily run a wire from the battery to the interior in most cars (maybe through the glove box?) or do you have to drill holes or do other stuff where you could really mess something up?

[lloydstrans]

Okay, determination, gotta love it. I assume you already have an inverter. Now throw it away. You should use a pure sine wave inverter not a modified sine wave inverter, easiest way to tell if you threw away the literature and the label fell off is cost. Pepboys etc. typically will sell modified sine wave due to price point. Look up power inverters (PSW) on the net. There about double the price. 400 watt would be my starting point. Lopping off the cigarette plug and hooking to battery, not too good.

[Veraster]

OK now I have a new inverter. How do I run a wire from the battery to the interior? There seems to be no obvious way.

[LoudRam]

OK now I have a new inverter. How do I run a wire from the battery to the interior? There seems to be no obvious way.

Usually there is a hole in the firewall where the other wires are ran. It might be buried behind something but it's there. It's easier to find from the engine bay.

[Xfactorx316]

If you have an automatic you can usually drill a whole through the clutch plate on the firewall. Near the brake booster from the engine compartment or the brake inside the car.