power inverter

[john112deere]

I think that's the word for the thing I want, anyway.

I'm thinking about buying a thing that plugs into a cigarette lighter, and gives a regular outlet.

The immediate need is to recharge my laptop, but I don't know what else I might need or want it for in the future. I doubt I'd ever be able to run power tools with it, though it would be cool if I could.

I'd like to find one locally because I need it this weekend, but I don't know where I'd be best to look- Circuit City, Best Buy, Radio Shack are all handy enough, but in different directions.

Nor do I know what specs I should be looking for...I don't want to buy one that's way bigger than I need (unless it's cheap), but I'd hate to find out that for another $5 (or whatever), I could have gotten one that would suit me a lot better.

Thanks!

 

[Brian_B]

I don't now anything about them, but I knew a guy with two of them in his explorer. One small one was mounted in the front center console to power his laptop. The other huge one was under the back seat. It was wired to a regular household plug in mounted in the back panel (by the hatch). He could plus all sorts of things into that one.

I had though about building a "jotto desk" and using my laptop in my explorer for navigation, but never got around to it. Now I don't go anywhere. LOL

 

[mrfixit]

Inverters, inverters... do I know inverters! Love them, live by them!
I have two in my peterbilt, one is a 400 watt, and for what you need, it is about the best thing going. you can buy it for around 30 dollars at walmart. Whisler is about the most dependable. Stay away from the cheapies, like roadpro, or coleman. The other one I have, also a whisler is a thousand watts. I run a microwave with it, and it is hardwired to my batteries.
The aforementioned 400 will even run a small TV, but you will notice when you first start it up, it will try to come on then switch to red... meaning it was overloaded. My whisler keeps retrying, where many others I had to stand there and turn it on/off til the High Tension Coil in the TV got enough juice built up in it.
I'd tell ya just to run to Flyin' J to get one, but I don't think you have one nearby, lol...

 

[Brian_B]

Whisler as in the old radar detector Company? Waly world has them or the Flying J?

 

[john112deere]

No, we don't have a Flying J nearby... During the school year, there's a Pilot about 60 miles south of me that I drive past fairly regularly, but it's gonna be about 30 miles out of my way this weekend, on what promises to be one hellish night anyway (work 7:00-4:30/5-ish, then drive 250 miles, either all back roads, or fight vacation/weekend traffic for the first 150 miles).

I'll look around for a Whistler, 400W. For $30, I'm sure I'll get my money's worth out of it over the years.

 

[mrfixit]

Yes, brian! One and the same company, lol... And BOTH Wallyworld and the "J" have em, but there's a different name on the ones at wally's. I'll have to look when I get home again.

 

[O'Rattlecan]

I have a cheap 70 watt Vector if you want it. I can mail it out tomorrow

Ryan

 

[Brian_B]

Well...there you go john112deere. Can't beat the price on that one.

 

[Brian_B]

This it?

Whistler 400-watt Power Inverter with Circuit Pro $27.67

Don't know if they are in the local store or not, but they have it online.

Item Description


A powerful, 400-watt Mobile Power Inverter that converts 12V DC to 110V AC for 800 watts of peak power. Also provides voltage protection, short-circuit protection and overload protection to a variety of devices. Great for use with TV/DVD combos, laptops, cooling fans and other mobile electronics.


Technical Information
Plug/Connector Type
Automobile Cigarette Lighter
Protection

Overload Protection
Power Protection
Short Circuit Protection


Power Description
Input Voltage
12V DC
Output Voltage
110V AC
Frequency
60 Hz
Load Capacity
400W / 800W

Miscellaneous
Additional Information

Smart Surge control
Voltage protection
Direct wire cables with clamps

They have a 200, 800, and 1200 listed too. Prices vary accordingly.

The big one would be good for power tools in salvage yards. Errr....ummm automotive parts recycling facilities....

 

[Bob Ayers]

Be very careful with the cheapy inverters. They can have some real bad looking output waveforms, not a nice sinusoidal waveform. For your laptop,
they make AC/DC power adapters for it that can take 120VAC, or 12VDC,
and I suggest this over a power inverter.

What brand and model is your laptop?

 

[mrfixit]

many of these newer inverters claim to produce a true "sine" wave... but I certainly do not mean to challenge your expertise... in fact I defer to it! But this Inverter has been running my laptop for a year and a half; I have a Compaq V5000. Could it be I haven't had a problem because it uses the transformer inline, and doesn't have the direct "AC" line in?

 

[Bob Ayers]

many of these newer inverters claim to produce a true "sine" wave... but I certainly do not mean to challenge your expertise... in fact I defer to it! But this Inverter has been running my laptop for a year and a half; I have a Compaq V5000. Could it be I haven't had a problem because it uses the transformer inline, and doesn't have the direct "AC" line in?

Normally the AC voltage goes through a full wave rectifier bridge, and the DC voltage feeds a switching regulator that runs at a much higher frequency than 60hz.

 

[slmann]

not to steal the thread but I'm not familiar with the subject. If I understand correctly you can put one of these inverters in your vehicle and use it to plug something in you would normally use in the house? Does the inverter simply plug into your car lighter or powerpoint or do you have to hard wire it in?

 

[O'Rattlecan]

most have a cig lighter adapter. If you'd prefer a hard wire, just lop it off, find a power point and a ground.

Ryan

 

[mrfixit]

The lower wattage ones have the cig adapter, but for ones like my 1000 watt, it must be hardwired, and have a decent battery to boot! Mine has 8 guage wire going to the battery box.

 

[mrfixit]

most have a cig lighter adapter. If you'd prefer a hard wire, just lop it off, find a power point and a ground.

Ryan

Also, you don't want to use just "any" power point. These things DO use a bit of juice, and you don't want to charge-back any sensitive electronics. Either use the Power Port/cig lighter or run a direct battery connection.

 

[Bob Ayers]

The lower wattage ones have the cig adapter, but for ones like my 1000 watt, it must be hardwired, and have a decent battery to boot! Mine has 8 guage wire going to the battery box.

One thing to remember: POWER = VOLTAGE * CURRENT

So, if you assume that these inverters are 100% efficient (which they aren't!!) If you have a 1000W load on the inverter, you are going to be pulling >80A on the 12V input to the inverter (1000W/12V). This is why
an inverter with this much power has to be hardwired directly to the batteries.

 

[john112deere]

What brand and model is your laptop?

I have two, which is why the inverter is a more appealing choice. Will using one with bad wave-form output damage anything, or are they just very inefficient? I don't know much about electrical stuff.

I have an IBM Thinkpad R52, that I don't use too much, and an Apple G4 iBook 12" that I use almost all the time. The Apple has more than twice the battery life of the IBM, though, so being able to recharge it is, in some ways, less important than the IBM. The IBM also has a bigger screen, so if someone wanted to watch a movie or look at pictures while riding in the car, it would be a better choice than the Apple.

Ryan- PM sent.

 

[blackhat620]

Be very careful with the cheapy inverters. They can have some real bad looking output waveforms, not a nice sinusoidal waveform. For your laptop,
they make AC/DC power adapters for it that can take 120VAC, or 12VDC,
and I suggest this over a power inverter.

What brand and model is your laptop?

I'm with Bob on this one, make sure you spend the money for an inverter that has "True" pure-sine wave output. Your sensitive electronic equipment will thank you in the long run.
www.donrowe.com/inverters/inverter_faq.html#modified
www.donrowe.com/inverters/puresine.html
www.roadtripamerica.com/dashboarding/Power-Inverters.htm

 

[Brian_B]

No way can I afford anything decent at the moment, but for later on....

How large of a Pure sine wave inverter would I need for my laptop?

Gatway, M685-E, Intel Core 2 Duo T7400, 2 gig of ram, 17" wide screen.