Alternate Way to Power Windows Notebook On-the-Go

[Nathan Parker]

Is there an alternate way I could power a Windows notebook on-the-go if I'm not around a power plug for a while, and if I needed power a little longer than could be delivered through the battery?

 

[Drew Terril]

Are you already running a power inverter in your car? That's the easiest way to have an AC plug in a car (although there are some, like my Titan, that have a built in inverter). If all you're running is a laptop, a small 400W one wired directly to the car battery will work fine. You can make a 150W one work that plugs into the DC socket, but that's a lot of amperage draw through that particular power circuit. Those circuits are usually only rated for 10-15 amps.

 

[Nathan Parker]

Thanks! I don't think I have one installed yet. I do have a DC Socket and USB Port in my car.

 

[Drew Terril]

Yeah the DC sockets are very limited on amperage. Newer ones aren't as bad, but they still have limits. A car audio shop will run the inverter cables through the firewall for you for a reasonable price if you're not comfortable doing it yourself. You'll want to have your inverter picked out first so they know how much power it needs to carry (that determines the gauge, or width of the wire needed).

 

[Nathan Parker]

Sounds good. The dealership that's certified to work on my card is close by, so that would be easy to do. Probably worth them doing it so that I don't messup anything.

 

[Drew Terril]

Not sure if your dealership will mess with that kind of stuff or not. I know a lot of them won't touch something of that nature. Even if they did, parts and labor would be high. They're generally fine for fluid changes and the like, but they get very pricey for anything other than that. Most of them won't even upgrade parts either. For example, the OEM for my Titan for the shocks and struts is Rancho. A Nissan dealership will only replace the OE spec with OE spec. They won't install a set of Bilsteins (which is a decent upgrade). At the time, I didn't have a place where I could work on things myself, so I had to have another shop do it. That's why I recommended a car audio shop. Best Buy would do it, but I'm almost certain that they'd charge a lot more than a local shop. Just google "car audio" and you should find quite a few results. If you were closer to OKC, I'd be able to recommend the place that did the same thing on my Titan.

 

[Nathan Parker]

Sounds good. Thanks for the info! I'll check for a local car audio shop. I know we have some. We used to have one mechanic who could do anything. He died a few years ago on a bike accident. We miss him.

My uncle is a parts manager of a dealership, so I'll probably ask him who he'd trust in this area. He should know who would be the best place to take it to.

 

[Randy Jennings]

If you are only interested in powering a laptop, then a DC-to-DC adaptor is the way to go. It is inefficient to covert DC to AC with an invertor and then plug in a laptop power supply (which converts it back to DC). I started out with a cheap one that lasted about a season, and then I switched to a LIND one and it has been rock solid for years. If you select Auto Adaptors on their website (Home - Lind Electronics) it has as wizard that you tell it your laptop make and model and it will tell you which one to get.

 

[Drew Terril]

While it is inefficient to go do DC to AC and then back to DC, the low amperage limits on those cigarette lighter outlets is always concerning. Even with what a laptop draws, that generates a fair amount of heat because it's towards the upper limits of what those small gauge wires can handle. Moreso if it's an older vehicle. If I were deadset on doing DC to DC, I would build in a standalone circuit for peace of mind. It's no different than directly wiring in a VHF/UHF ham radio, even though they do sell DC outlet plugs for those. More risk involved than I'd be willing to take. Most vehicle fires these days start out from the electrical system.

 

[Nathan Parker]

Thanks for the info. By the way it's a 2015 FIAT, and the notebook I'd be connecting is my HP Windows Notebook with an Intel CPU/GPU that would be running my Baron MTN receiver.

 

[Randy Jennings]

What Drew says is true - it is always best to go direct to the battery with quality wire of the appropriate gauge. The bets solution would be a quality DC-to-DC convertor going direct to a batter (vs thru a cig plug). Having said that I would not worry about using a "cig plug" for powering a DC-to-DC laptop converter, especially a LIND one. Two reasons for that 1) Modern laptops don't draw much power and modern cars are designed knowing folks are powering electronics and not lighting cigarettes, so the wiring is a tad better than it used to be (milage may vary on that one - depends on the car), and 2) The LIND ones are fused very well, so really you are double fused with car and the LIND adaptor (to be fair my original cheap one had a fuse too, but it was an inline one in the cig plug). I'm a little gun shy of inverters because of the heat they produce, and I once had a guest chaser with me who plugged an inventor into my cig plug and promptly blew the fuse to my cig plug.

 

[Drew Terril]

I was OTR trucking for several years and had a 2000W inverter wired directly to the batteries. Powered my microwave and coffee maker. I have no desire to use one of those plug in inverters.
And I would point out that Fiat (and also Chrysler made vehicles in general, both before and after FCA emerged from the merger) are notorious for electrical issues. I wouldn't be with *as* hesitant going through the DC plug with a Toyota, but if I'm not going to use a DC plug for a 50W ham radio (and I can't think of anyone that actually advises that course of action), I'm certainly not going to going to run my MacBook Pro that draws nearly 100W.

 

[Randy Jennings]

I suspect your ham radio draws a lot more than 50w. My Yeasu is spec'ed at drawing 11 amps at 13.8 volts when transmitting on high (50w). That is a 151.8w power drawn. I looked at the specs for the most popular Kenwood, and it is spec'ed at "less than 13 amps" at 13.8 volts when transmitting at 50w, a 179.4w draw. But you are totally correct - cig plugs are best avoided regardless of if you are using an inventor or a dc-to-dc adaptor.