# Power Draw Of A 12v Tv?



## BritStops (Mar 3, 2011)

Hi everyone,

I do realise at sometime I'm going to have to bite the bullet and spend some time learning about the calculations needed to properly get to grips with all this electrical stuff (you know, amps divided by volts times watts or something like that... :roll: :lol: )

In the meantime, our TV currently only works when we're on hook up via an on-board 240v plug socket. I've now bought a 12v cigar socket adaptor which will run it from the dash socket. Eventually I'd like to wire the spare 12v socket next to the TV to the leisure battery (it's currently wired to the hook up power, same as the 240v socket).

So, my question is: how long can we run the TV/DVD when plugged into the dash socket and still be able to start the van?

My daughter uses a DVD player plugged into the same dash socket and so far has watched a couple of films a day over a couple of days without making a dent on the battery (or so the control panel tells me).

Will a 15" LCD TV draw noticeably more?

Thanks in advance.

Steve


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## clive1821 (Mar 27, 2010)

Hi Steve, if your tv works ok from the engine battery then give your idea a go you have nothing to loose.... It would he helpful to know what current your tv is using at 12 volts so I could give you an idea of the battery life assuming you have a 110ah battery.... Currys is a good idea to get a tv from..... Which works very well for me...

Something like this one for example

http://www.currys.co.uk/gbuk/logik-...tv-with-built-in-dvd-player-09902320-pdt.html


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## BritStops (Mar 3, 2011)

Hi Clive, thanks for that.

Yes, it's a 110ah battery (adding a second battery is on the "to do" list). I'll see if I can find out what current it's using at 12v - will I need a multimeter for this? (you can tell this electrickery stuff is all new to me...)

I'd rather not power stuff in the van from the engine battery if I can help it, but as we spend quite a lot of time at shows off hook up it'd be useful if we could power the TV. Just want to be able to drive off when the show's finished!


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## Wizzo (Dec 3, 2007)

The new LCD/LED backlit (or sidelit) tvs use less power than their LCD equivalents. A 15" LED tv would consume around 2a, possibly marginally less on tv and marginally more on DVD.

I occasionally use my vehicle battery when off EHU. I can normally get 2 days use out of it without compromising its starting ability.

JohnW


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## clive1821 (Mar 27, 2010)

BritStops said:


> Hi Clive, thanks for that.
> 
> Yes, it's a 110ah battery (adding a second battery is on the "to do" list). I'll see if I can find out what current it's using at 12v - will I need a multimeter for this? (you can tell this electrickery stuff is all new to me...)
> 
> I'd rather not power stuff in the van from the engine battery if I can help it, but as we spend quite a lot of time at shows off hook up it'd be useful if we could power the TV. Just want to be able to drive off when the show's finished!


So if for example we say you have a 110ah battery at a temp of say 10c your usefull storage would be about 65ah then the tv would last a good day and a half... :wink:


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## BritStops (Mar 3, 2011)

Thanks John, sounds like we might be ok then.

We already have the TV (came with the van). It's a MobileTv MTV15DVDT. Don't know if it's got LED backlighting, but suspect not as it was installed in 2008 I think.

Steve


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## BritStops (Mar 3, 2011)

clive1821 said:


> BritStops said:
> 
> 
> > Hi Clive, thanks for that.
> ...


So to get this right, when you say two days or "a good day and a half" do you mean we could have the tv running _constantly_ for that time?

Or do you mean a few hours a day for a couple of days? Hasten to add we don't actually _want_ to watch it for that long! Just need to know when to tell tv addicted daughter it's time to switch off!

Steve


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## erneboy (Feb 8, 2007)

The power consumption will be written on the back of the telly or on the power pack if there is one, from that information you can work out exactly how long you can run it, Alan.


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## BritStops (Mar 3, 2011)

Hi Alan,

Back of TV: 
AC100-240CV ac 50/60Hz
28W DC 12-24V

240V Power pack:
Input: 100 - 240V ac 50/60Hz 2A
Output: 12V 4A

12V adaptor pack : 
Input: 10-13Vdc 11A max
Output: 12V 6A
Max output power: 72W


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## clive1821 (Mar 27, 2010)

Yes Steve it's just over or around 2amps so you might get around 30 hours out of your battery if you just used the tv and nothing else :wink:


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## BritStops (Mar 3, 2011)

clive1821 said:


> Yes Steve it's just over or around 2amps so you might get around 30 hours out of your battery if you just used the tv and nothing else :wink:


Excellent! Thanks!

So with our new LED bulbs my daughter should get a few DVD viewings and / or maybe a couple of evening's TV viewing and we should still be able to drive away at the end of the weekend! 

A non-grumpy 12 year old always helps when away! Roll on Romsey, Shepton, Chepstow, et al! :lol:

Thanks everyone.
Steve


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## clive1821 (Mar 27, 2010)

No probs Steve, pop along and see me, if you need some advice, I'm at romsey, shepton :wink:


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