Power Inverter

ruauman2 · 11-07-2004, 03:56 PM

I just bought a 400 watt power inverter at Costco for $25. I'm still thinking about how to install it. I wanted more watts but for the price, I'll try it out and get a larger one later if I need it. Has anyone else installed one and if so can you tell where and how it is installed. Thanks.

sireousrex · 11-07-2004, 04:08 PM

400w is alot already. A PS2 only consumes 75-80w if I remember correctly. You should be fine with 400 unless you are installing a fridge. I spliced into the rear power outlet under the console and ran the wires coming out under the passenger seat where it is mounted. Good luck.

Doghouse · 11-08-2004, 09:56 AM

Power = amps * volts.

400W / 110v= 4amps. Since most equiptment lists amps not watts, that will help you calculate the amount it can run.

Another thing to consider is the draw on the battery. If you consider that without any loss due to 12/120 DC to AC, the draw on the battery should be in the 30 Amp range at peak usage. I would recomend that you run wire designed to handle that draw directly to the battery. Not only will you reduce loss using larger wire, but by going directly to the battery, the battery will filter out some of the engine noise.

New_England_Titan · 11-09-2004, 07:21 PM

Quote:

Originally Posted by ruauman2

I just bought a 400 watt power inverter at Costco for $25. I'm still thinking about how to install it. I wanted more watts but for the price, I'll try it out and get a larger one later if I need it. Has anyone else installed one and if so can you tell where and how it is installed. Thanks.

http://titantalk.com/forums/showthread.php?t=14627

RoscoeJohnson · 11-24-2004, 11:39 PM

I got the same 400 watt inverter at Costco. Make sure you read the directions. If you plug it into the vehicle's power port, then you can only use 150 watts. In order to get the full 400 watts, you need to clamp it to the battery. After I realized this, I went back to Costco and got the 1500/3000 watt power inverter for $85. I put the 400 watt inverter in my wife's car. I am having a local car audio shop install the 1500 under the driver's seat. It will be hard wired to the battery with a circuit switch in the engine compartment. You need the circuit switch for two reasons. First, any overload will trip the circuit. Second, if you don't have the switch, the inverter will constanly pull power from the battery. It is a small amount, but over time it could drain your battery. Since the inverter will be under the seat, I am having them hard wire some extension cords to the inverter.

honeykeeper · 11-25-2004, 06:52 AM

Exeltech makes pure sine wave inverters=====clean output waveform......if yours is a cheap square wave one you'll be very dissapointed and your appliance will not last long either.

bestatchess · 11-25-2004, 09:20 AM

Quote:

Originally Posted by Tom Mincarelli

Exeltech makes pure sine wave inverters=====clean output waveform......if yours is a cheap square wave one you'll be very dissapointed and your appliance will not last long either.

Yeah, be sure to check your intended application before buying an inverter. You might need a pure sign wave inverter, which costs alot more. I have been using a 150 Watt pure sine wave inverter which plugs into the power sockets in the truck w/o blowing the fuses. I was afraid of frying my laptop or my kid's video game with a chopped square wave inverter.

Titan Ken · 11-25-2004, 07:53 PM

So are you guys saying if I use the Costco 400watt inverter to power my laptop computer, it will fry it? I bought the inverter with the intention of using it occassionally in my travel trailer for the computer. Would it be easier on the deep cycle batteries to run the computer or would it be better to simply recharge the computer battery from the inverter and then run the computer from it's own internal battery.

I'm thinking the inverter would run for a much longer time charging the computer battery, but perhaps the load draw would be less than running the computer for short periods of time. Don't know, that'w why I'm asking.

Thanks for any advice on this.

scr38 · 11-25-2004, 08:37 PM

If all you want to do is run your laptop from the truck battery there is a better way to do it. Instead of using a inverter, buy a DC to DC converter. This will be more efficient. Why convert the 12 VDC to 110 AC and then convert it back to DC for your laptop? There are many DC to DC converters available. Look at your AC power supply for your laptop and find the output voltage and amps. Then buy the DC to DC converter (called car chargers) that meets the DC voltage output of your AC power supply, and has a current output that is at least as much as your AC power supply. A higher current output won't hurt, but you need at least as much as the AC power supply. For example, my VAIO laptop requires 19 volts DC and 6 amps. I found a car charger on eBay for it. There are many listed.
I have a new one I bought that is a universal type with selectable output voltages of 15, 16, 18, 19, 20, 22 and 24 volts DC out. The maximum output current is 3.5 amps, which isn't enough for my new laptop. I can give you more info if needed.

honeykeeper · 11-26-2004, 05:01 AM

scr38 is correct.......instead of merry-go-round from 12vdc to 120vac then back down to your computers voltage get the dc converter.....from your computer manufacturer is what I recommend.....forget the ac inverter......when you need ac for something else....get the more expensive to buy......sinewave one.....so you don't fry your ac toys. Square-wave inverters also fry scr's in cordless chargers or variable speed drills etc. Good luck....anymore inverter info....needed let me know.

Titan Ken · 11-26-2004, 01:30 PM

Thanks for all the advice. I picked up the inverter at Costco because it wasn't that much ($24.99 I think). I know 12v laptop power supplies are spendy. My nephew priced one at over $100 at Circuit City, and they told him to just use an inverter.
Other than the 12v-120v-12v merry-go-round, would using an inverter likely harm the computer?

jasonwabc · 11-27-2004, 09:07 PM

I know that modified sine wave inverters are not "perfect power", but I have ran 2 different laptops, cordless drill chargers and cell phone chargers for several years without any problems.

I have had a cell phone battery burn out with a defective (cheap) 12 volt cell charger that overcharged and overheated my battery....that is when I just took an extra house charger and use it with my inverter. I have used my inverter to charge my cordless drill for the past 2 years.

My wife and I both use our laptops with cheap 150-300 watt inverters...I have even let my daughter watch dvd's on long trips that last all day using my laptop.

I would never try to run a laser printer or microwave on an inverter, but for light use, a cheap inverter will usually do the job.

honeykeeper · 11-27-2004, 09:21 PM

Ken.....you might notice your power supply running hotter temps. from the Square-Wave inverter..check the DC output from the charger and then...check the ac output of the inverter....if it is a square wave one you will need a true RMS meter or it will read below 100 volts.....anyone using an inverter should size it so your loads are at the inverters maximum efficiency range.which might be 80-90% at best. You can pick-up cheap used DC converters from E-Bay...and everything will run cool and no buzz/heat. I have fried some AC toys on modified-square wave inverters......and power my home entirely from a 4,000 watt continuous rated Mayan-Step-Sine-Wave-Inverter. Good luck.