power invertor

[SDPROV]

Got an invertor question. If I put a invertor on a deep cycle battery how long would a small tv/vcr combo run on that? Or would that even be enough to run it??? Taking the kids to the lake for the weekend and would like to watch a couple of mpvies without having a generator. Thanks

[tip-up king]

I used to be able to get 2 days out of my trolling motor deep cycle with a 400W inverter running an fm radio and or a 13"combo tv. You shouldn't have a problem.

[JimBuck]

Your inverter has a rating for amount of watts it is capable of handling. Make sure this rating is greater than the amount of Amp draw from your TV/VCR.

Then to figure out the amount of hours you will get from your battery take the amount of amp hours (on battery) and divide by the amount of amp draw from the device.

I think you'll be just fine.

[eyebjim]

Check how many watts the tv combo uses. This should be on the label on back. Most will be around 40-80 watt. Add about 10% for the inverters losses and then divide by 12 (volts of battery). This will be how many amps of current draw from the battery. Now find the amp/hour rating of the battery. A 29 series deep cycle will be around 200. divide this by the current draw you already calculated and you will get the approximate run time. In this case about 27 hours if 80 watt draw.

[JCR]

Assuming the small TV draws a 100 watts, The invertor should draw around 10 amps (10*12=120). Assuming the battery is 100 Amp-hour you should get about 50 usable with the various inefficiencies. So It should last around 5 hours(5*10=50). Maybe a bit more if you are lucky, find the exact time by changing the assumptions appropriately.

[herefish101]

so which awnser is right, three people three diffrent way's of figuring. I like this question, mine works for about four movies, unless one of them is really long. but then i'm using an old battery so it just dont hold the juice like it used to.

[eyebjim]

Acutally all three are more similar than you are thinking.

Jim buck had the same formula as me just didn't explain how to get current draw from watts. LCR used the same formula too but included a loss factor of 50% of the amp hours of the battery adn no lass factor for the inverter. Most inverters will lose or use up about 10% of the power usage of the load in the process of converting to AC. Also a battery can not supply 12vdc for the entire amp hour rating of the battery but it can still produce a 1 amp. You will likely get more like 80% of the amp hour rating.

Anyhow another reason all times were different is we we using different wattages for the load and different amp hour batteries. The overall formula still holds true.

[MNfan]

Two weeks ago at Red Lake we ran a 19" flat screen TV and a Direct TV satillite reciever with a 400 watt inverter for 17 hour on a battery. I dont know all the wattages and draw times I am more of a do it and see how it works kind of guy. Except if the box says 12 cans or 24 cans I know how long that will last but I guess that is from experiance also.

[crappiekid]

goto big box store and get a 49.00 12 volt dvd player for your auto. This will work for the ride and also in the FH . My unit will play all weekend on a deep cycle batt. The kids watched alvin and the chipmunks 10 plus times.

[SDPROV]

Thanks guys I think this will definitly work for what I want to do!