12v tv vs. 110 tv with inverter?

I'm looking to buy a flat screen tv in the next month or two for my 5th wheel, something 20-24". I expect to see them pretty cheap around black friday, but only in the 110 version. My rv is my "vacation home" in Tahoe. I normally have it plugged in to 110v in the winter, then move it to a friends unimproved property in the summer and boondock. I have a couple of 6v Trojans that are not in great condition, but have not failed me yet. These are hooked to an 80w solar panel. I'm only there on the weekends, so the batteries have all week to charge.

When at the 5th wheel in the summer, I don't use much power.  A little juice to run the radio (12v car stereo), a few LED lights and the heater fan sometimes at night, if it gets cold. The 5r is a pretty basic 1997 model, so really no extra power draws. I just installed a progessive dynamics power unit to replace the old magnatek, thanks to info on this board.

I looked online and it seems a 32" lcd tv uses about 125 watts, so I assume a 24" tv will use a little less. However, I'm also looking at the tv/dvd combos, so maybe 125 watts is about right for the combo. I can't find anything online about

Here's my question: Will the 110v tv drain my battery significantly faster then the 12v tv? Lets say I'll watch a 2-3 hour movie, with a couple LED lights plugged in, and still need enough battery power to run the heater fan (the one built in with the propane heater) for an hour a night.

Thanks for any input!

Power consumption is power consumption, no matter whether it is 12v or 120v.  However, using an inverter will consume a small amount more than using straight 12v, though I doubt if you would detect the difference.  One advantage in using an inverter is that it is available for other 120v devices when needed - size chosen considering other purposes.

It's somewhat ironic that, when you're running a 120 volt TV off an inverter, the inverter has to invert 12 volts DC from your batteries to 120 volts AC, and then the TV has to convert 120 volts AC back to a lower DC voltage. Both processes waste a bit of power.

I've always wondered which TV would be most efficient, a 120 volt AC TV or an equally sized 12 volt DC TV. In the end, I'm pretty sure Tom's right, it wouldn't make much difference. just curious.

Kev

Ii have 3 flat screens here all low=cost for one reason or another.. My first was more expensive but it died of old age so I won't talk about it except to say it was a Samsung (This is improtant later in the story) I sent it to a re-cycler.

The second was a Black-Friday special at Wal*mart,  As I recall it is a 21 inch and about 100 bucks.

The original Samsung was NTSC only, but it had Picture in Picture so I could watch TV while using it as a computer monitor, the new one did not have that feature so I needed a 2nd 21 inch to set beside it....  Wal*mart had a SAMSUNG on the scratch and dent shelf, a former floor display they had LOST the remote.. I figured I could use a universal till i got a proper remote via E-bay or some such.. Turns out that one i recycled (Remember I said it was important later).... Same remote codes and I did NOT recycle the remote.. Yup works 100%.

This Samsung uses a "Brick" power supply....14 volts

14-10% = 12.6 (normal fully charged 12 volt battery voltage)  14*10% is 15.4 (downright close to the max output voltage of my PDI 9180 with wizard) and in electronics normally we ignore 10%, and often tollerance is 20% so I suspect if I choose to power this rig with house power instead of shore power it would work perfectly.  That said I use the brick. Works great.


One other thing: in the 21 inch class different TV's have different features,, Most all of them accept RF (Both ATSC and NTSC) HDMI, and A/V, some also accept Component (P.B.Y) and Most have VGA (Computer monitor) input and most have a USB port.. now this is where the fun starts.

On the off brand the USB port is a time shifter... Plug in a thumb drive and you can "Pause" a program (just one near as I can tell) or even record it fully and then watch it... There are some restrictions like I do not know what happens if you turn off the TV.

On the Samsung I can load up a thumb drive with MP4s (or MP2s) and play them directly without using the computer.

My suggestion is get the features you want.

Converter loss (both from battery power to 120vac and from 120vac to whatever the TV actually uses) is about 10% so yes a 120 volt unit uses more power, nearly 20% more, but these things sip compared to the old tube type they replaced so it is 20 percent of next to nothing.

I recently converted my huge old heavy archaic type 120 volt AC TV to a 12 volt 32" HD LED and I love it... the picture is so much sharper and it the screen is correct for most movie size formats.
I know it draws very little 12 volt power because it has a 5 amp fuse (60 watt max) on the cord, and it is listed as a normal 30 watt draw. it was about $285 on Amazon.

I did this strictly because it made no sense to take 12 volts DC (while dry camping) send it through an inverter (with some power loss) and convert it to 120 volt AC so it can go into the average TV and be converted back to low voltage DC.
and then the fact that most modern HD LED or LCD TV's need a pure sine inverter and my inverter is an older model modified wave inverter.

So, The one I bought is a Jensen 32" LED. its very thin and very light I mounted it to a swivel mount bracket so now I have this huge storage cabinet behind it. I had to make up a wood panel below it to cover the HUGE hole the old TV was in..but the picture size is actually larger on the new TV.
the old TV took my daughter and I to carry it out on the motorhome and the new TV weighs 12 lbs. so there is also a weight savings of about 60 lbs.
There already was a 12 VDC cigarette lighter plug right there behind the old tv so all I had to do is buy a 12 volt accessory plug and put it on the TV power cord. 

The only complaint I have is the stock speakers on the TV are kinda tinny sounding so I have them disabled and run it through the surround  sound  DVD player........ now I'm searching for a 12VDC DVD player.

here's a pic of it...(sorry turned  sideways)

We replaced an old 12V with a new flat screen.

The picture is bigger and better plus the flat screen
uses lass electricity.

Looks good Tony.

Kev

Here's the one I bought. I use it in my bedroom at home and in the MH when we use it. It has a great picture sound is ok for a lcd tv that small. I've had it a couple years and use it daily. It comes with both cords, I just leave the brick in the bedroom at home.

http://www.ebay.com/itm/22-Naxa-NTD-2252-LED-12-Volt-AC-DC-Digital-HDTV-w-DVD-/301183089024?pt=Televisions&hash=item461fe93980

Last year we used a TV/DVD combo that I replaced the brick with a 12v cord. It worked fine and not going from 12v to a inverter with it's losses converting to 120v and then back down to 12v via the brick had to save power.

This year we are using a Satellite system since there in no reception and it requires 120v. So there was nothing to gain in keeping a TV that would run off of 12v.

I'll have to find it but on another board a poster bought a flat screen that once the brick was replaced it used just 25w running.

Tony Dtorch, I would love to find the 32" Jensen tv for $285 but all the 32" Jensens I see on Amazon are running $600 or more. Model #?

Thanks,

Steve

Livewire said:

Tony Dtorch, I would love to find the 32" Jensen tv for $285 but all the 32" Jensens I see on Amazon are running $600 or more. Model #?

Thanks,

Steve

Click to expand...

The one I bought was listed as "reconditioned" it was a great deal so I bought it, here is the place I found the cheapest ones before that. I copied and pasted the model number on google search and found that reconditioned one for sale.

but here is one for $515....................http://www.my12voltstore.com/32_LED_LCD_Television_p/je3212led.htm

Thanks!