Flat screen TV

[EdHouston]

Ok all knowing wise ones!

Here is a question for you all. Been looking at putting a Flat screen TV on the boat to entertain the grand kids. Seen a nice 18.5" one at Walmart less than $200.00. Here is the question: are these TV sets 110vac or do they actually run on 12vdc I seem to think the later and that they probably have a built in transformer to drop the 110vac.

Any thoughts comments would be greatly appreciated.

I have the skill to rip one apart and hot wire around the transformer if that's the way they operate!

Ed
S/V Moonlight Mile

[slokat]

Hmm was just thinking of using my Samsung 21" multi input monitor coupled to my xbox for watching videos on board...  it has a built in power brick. Would be hard to hot wire it. I was intending to use it with shore power...

Make sure it's really 12v.

[kevin barber]

I used to have a Sharp LCD that ran on 12V.  I had to replace it with a new one, and it is 110V.  I tried finding another 12V model, but couldn't find one.   I don't believe you will be able to use the newer 110V models.

[RayNWanda]

I looked at this about a year ago. Best I could tell, some ran on 12vdc and some did not.  Our boat has a flat screen and DVD player, but both are 120 vac.

[RayNWanda]

Looks like the easiest way is to find one that has an external power brick.

http://www.casitaforum.com/invboard/index.php?showtopic=4629&hl=Television

[Jim S]

Will a cheapo inverter do the job?

[EdHouston]

Inverter?

Never had any experience with one what is the power drain on the battery bank?

[RayNWanda]

 We have a 1250 watt inverter, a flat screen and DVD player, but all I have plugged in to the inverter is a drop light to see if the inverter worked. I have turned on the TV and DVD player on shore power and they both work. If I can find my Amp Probe, I will plug the tv in to the inverter and give you a report when I get back home. I am offshore now.
A couple of things to look at- A lot of RV'ers have tv's in their travel trailers. You might check some of the bigger RV places. There is PPL Motorhomes there in Houston that I have done business with- they may stock 12V tv's. They have a big web site. Also, look at the specs on AC tv's and see what the amp draw is. That will tell you what size inverter you need. Check the specs on that size inverter and see what the max amp draw is. That will give you a pretty good idea of what the load is going to be.

[Jim S]

Electricity used is electricity used, whether ac or dc.  An inverter will use slightly more electricity for an application because of the conversion, but it is slight.  More of a concern would be if the "inverted" electricity is compatable with the application...it usually is.  Ac appliances are usually much less expensive (and better selection) than dc appliances because of the mass production. We have had no problem running all of our ac appliances on inverted electricity.

[RayNWanda]

Somebody long ago (Ohm? Murphy?) wrote laws telling electricity how it would behave and it follows those laws to the letter. ( Why can't we get kids to do that?) When you raise the voltage 10X, there is a price. You pay the price on the input side in amps. I went on Xantrex's site and looked at inverters. A 1000 watt inverter gives you about 9 amps output at 120 VAC. They don't tell you what the input amps are at full load? All they tell you is that the input wiring is to be #2 and no longer than 5 feet. That input wiring is good for 70-80 amps, probably. The input wiring is sized to operate the inverter at full load. As long as you have the battery bank to feed it and the charging system to replace the amps, life is good.
No longer than 5 feet...This explains why our inverter is mounted directly above the sink. I intend to move it under the overhead dish rack. I will pull in welding cable to feed if necessary. Over the sink is a BAD place...

[SailingSeaDragon]

All,

A little information on inverters, types, prices, draw, and sizing.

http://www.theinverterstore.com/tips.php#2._Difference_between_modified,_pure_and_digital_pure_sine_wave_inverters

Garner

[Jim S]

Thanks for the information site.  I think 5% loss during the ac/dc inversion is acceptable.  Inexpensive ac blenders (maybe $12) run well and are a fraction of the cost of a 12v blender.  This whole energy situation seems to be a slippery slope where we want all (or even more) of the conveniences of home and need the power system to support it.  The big powerboats have no problem...they run big generators 24/7.  Maybe the Pardeys have it right, go simple-that won' run out of amps.

[RayNWanda]

You can use the following formula to determine the size:

Volts * Amps = watts

or

Watts / Volts = amps

1250 Watt example:

1250 / 120 Vac = 10.41 amps ac (typical number found on equipment)

or

1250 / 12 Vdc = 104.1 amps dc (battery drain per hour)

This was what I was looking for earlier and could not find. You have to put in 104.1 amps DC plus the 5% loss to get 10.41 amps out AC. Inverters are great- we are going to keep ours (just not above the sink). But you do have to be careful what you run with them. You can pull a fairly substantial battery bank down pretty quick.

[jackjanos]

There are several nice 12 volt TV's available.  Check with RV or Truckers places.  These folks have 12 Volt TV's that don't need an inverter (and most come with AC adapters to run off of shore power too).  I just got a nice 19" one from a Trucker stop in Baltimore.  It draws 5amps when plug in to the cig-lighter outlet.  I originally Googled "12 Volt TV's" and found that there are many choices.  When I got to the Trucker's stop, I got lucky and found the one I wanted was ON SALE (a $375 TV for $299 with a DVD player).
Jack