12 Volt TV/DVD

[sailingdog]

Actually, IIRC, it was all TVs made after March 2007 were required to have on-board ATSC (digital) tuners built-in.

Originally Posted by camaraderie

All TV's made since march 2007 HAVE digital tuners built in....by law!

The all in one TV's are all standard resolution (400lines) on DVD's. Eventually all DVD's will be blue ray...but you can also buy one later and plug it in to your dvd/tv if it has an HDMI input.

[AnnaDor32]

Thanks Jody. I didn't want to go up the mast for the TV anyway.
Michael

[tjaldur]

I do agree with hellosailor that 12 volts are hardly ever 12 volts in a boat. The tension will vary between 14,4 volts - 11,7 volts, depending on automatic bilge pump, refrigerator, windlass, starter motor etc. In my opinion, if one is considering using applications that normally uses 220/110 volts, it is better to use a pure sinus inverter. That will give the applications a stable tension/current.

Once having an inverter, the advantages are many. An example may be having a coffee-mill to grind my espresso coffee from whole coffeebeans. Freshly grinded coffee beans just taste so much better. My (1200 watt) windlass has its own 230 amp battery bank close to the windlass, with its own dedicated 20 amp charger. The current is transported to this battery bank in 220 volts. That means much thinner and cheaper cables.

TV, computer, stereo, coffeemill, other powertools (that require clean current) are getting a stable 220 volts and the cabling and applications much simpler and cheaper. Even the heating of hot water for shower etc.

The inverter gives 1500 watt. The battery bank is 460 amps and it is charged with solarpanels and a windmill. If needed I also use a gasoline driven generator that gives 2,5 kw. But the generator was inexpensive, so the current from it is not stable. The charger is 60 amps and very forgiving conserning varying tension from the generator.

[nk235]

Ok so I went shopping around today and before I actually buy anything I just wanted to confirm a couple quick things. I am semi retarted when it comes to anything electrical so please bear with me...

I am planning on buying a tv like this one:

15" Marine / RV LCD TV/DVD Combination System

May not be the exact one but one that has the option for either AC or DC through the connection of a 12volt plug that connects into the cigerrete outlet.

Since my boat is already wired for a 12volt TV/DVD in the spot I want to mount it I was planning on connecting a 12volt recepticle like this:

West Marine: Receptacle - 12V, Stainless Steel Product Display

That way I can just plug the tv's 12volt plug into the recepticle and it should work right? Here are my questions. The two wires that are already run through the boat for a tv are yellow and red. Aren't these both positive? I thought there should be a black one in there for the negative? It seems all I have to do once I get the recepticle is just connect the negative wire to the "-" and the positive to the "+" and that should be it right? Which is which though?

Second question is the TV I listed says it draws a max of 4.2 amps. Again please don't kill me for asking dumb questions but is this a lot of power or a little? I have 3 group 27 gel cells for my house bank.

Thanks again so much in advance

[US27inKS]

Originally Posted by nk235

The two wires that are already run through the boat for a tv are yellow and red. Aren't these both positive? I thought there should be a black one in there for the negative? It seems all I have to do once I get the recepticle is just connect the negative wire to the "-" and the positive to the "+" and that should be it right? Which is which though?

The color of the wire has nothing to do with the power going through it. You could have a lavender wire with a hot pink stripe and it really means nothing. Red and black have become "standard" with positive and negative, but you apparently didn't install the wires and there's no reason to trust that the PO wired it right. To test the wires, get a 12 volt test light. Put the alligator clip end on the negative post of the battery, then the probe on the wires one at a time. When the light lights, you've found the positive. Now move your clip to the positive post, and find the negative wire.

[sailingdog]

Nk235-


As pointed out above, the "12 Volt" system on your boat doesn't really put out 12 VDC... it can range from as low as 11.6 volts (if you're batteries are close to fully discharged, up to 14.5 volts, if you're system is being charged, say by an alternator. Whether a 12 VDC TV that is using a transformer, which has a much more stable and consistent power output, can work under those conditions without being damaged is questionable.

The recent changes to the ABYC code have changed the DC ground wire from Black to Yellow. This is because boats with an on-board AC system will generally use Black for the hot AC wiring, and to help reduce the possibility of accidental electrocution due to confusion between the two Black wires.

Your house bank is probably about 300 amp-hours or so... Not using anything but the DVD player, you could operate it for about 30+ hours before you would reach the 50% discharge level. If you've got some sort of passive re-charging source or a decent shore-power based charger for use at the dock, you should be able to get away using it for a couple of hours each night on a weekend trip.

[camaraderie]

Yellow or Black is negative on a boat under ABYC standards. Red is positive. Red connects to the center terminal on the plug and yellow to the other "outside" terminal.

A group 27 gel will have about 90 amp hours of capacity so three will have 270 amp hours. You can use HALF of that between recharges or 135 amp hours. 4 hours of TV/DVD watching will "cost" you less than 20 amp hours.

No dumb questions I've seen...just inexperience. How else can we learn?

[US27inKS]

Dog, the tv he posted a link to is an AC/DC compatible tv. I would assume that they took voltage variation into consideration when building it.

I didn't realize that ground had changed to yellow. Nice to know.

[tjaldur]

Just out of curiosity, how much does a portable computer cost, compared with a TV with a DVD player in USA? Here in Norway the price will be about the same. With a portable computer and an USB TVTuner one has a complete mediasystem.

Together with my laptop I have an external 19" lcd monitor, an external 300 gig hardisk and wireless keyboard and mouse. That way the laptop is stored and well protected in a bookshelf and I can display TV, DVD, photos or chartprogram on the external monitor and have only the keyboard and the mouse out. If by some freak accident water should enter the steeringhouse, the keyboard and mouse are easily replaced

[sailingdog]

US27inKS-

A decent transformer will have relatively little fluctuation of voltage level in it nowadays. Even if the TV were designed to handle ±10% voltage levels, 14.4-14.6 VDC is well out of that range, and that is what a "12 volt" appliance might see when the boat's system is charging the batteries.