LCD tv voltage

Alrob

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is it not possible to run a small flat screen from the boats 12V system as I notice I have a transformer attached to 17" in my kitchen ???
 
12v LCD TV

Just about all LCD TVs upto 19" run on 12v, above 19" they tend to be 20 - 24v.
I have a 19" with integral DVD player that is running off my service batteries. I have noticed that the DVD player takes a much higher amperage than the TV alone.
 
I have used a 12 volt TV on board for 5 years now but the first one died very quickly. So with the second one I have used a voltage stabilizer to stop the voltage rising to much when the engine is running or mains charger is switched on.

About 20 years first with a CRT and recently with a LCD. Powered off the battery bank that hopefully will dampen any voltage spikes from charging systems. Last famous words ......
 
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You have two issues. Your battery will be charged at 13.5 to 14.5 volts by the alternator. Your set may or may not work with this higher voltage and may in fact be destroyed. The other issue is voltage spikes generated by the starter and alternator which can also see your TV off. The spikes will require a filter consisting of ferrite cores and small capacitors. The high voltage will require a stabiliser or regulator. A commercial product, if available, will incorporate both features and if someone knows where to buy one is the way to go. It is possible to build a DIY one which is what I would do for myself.
 
If one is worried about voltage spikes etc and one should be! Run the set through a small inverter, then the normal transformer, saves any problems.
 
If one is worried about voltage spikes etc and one should be! Run the set through a small inverter, then the normal transformer, saves any problems.

This is what we have done with our cheapy Comet 15" LCD DVB/DVD (12v) TV. To overcome any voltage fluctuations when on shore supply or low battery output, etc., we fitted a 600W inverter (connected directly to the battery), feeding a 240VAC 13A outlet - with a note that to be used only with the TV power supply unit or mobile phone charger.

Used for two seasons and no problems - except the TV came a cropper in rough seas and the case is now superglue'd back together!! Still working!!
 
I just cut the lead the tv side of the transformer and plugged it in via a 12v 3 round pin plug,no trouble after 4 years.
 
Are you suggesting an inverter is only 50% efficient?
Not in my experience they arent, normally with a modern one about 87% efficient and a pure sine wave one more like 95% efficient. Anyway, what I'm suggesting is a way to stop any voltage spikes destroying the equipment.
 
Very few makers specify the working voltage of their sets as they expect you to use the mains adapter supplied. Some will tolerate overvaoltage some will not, you only find out when it fails! (Expensive!)

Using an inverter can solve the problem, but some of the cheaper ones have a square wave output which again screws up the elctronics - though usually not terminally!

The cheapest and simplest answer is one of these: http://www.maplin.co.uk/Module.aspx?ModuleNo=228639

You just need to make sure you buy one rated to give enough amps to run your telly - the mains adapter supplied should have the power rating marked on it. Get an equivalent car adpater, and you are there.
 
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