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Help please

Hi This may be a little OT for this group but would rather ask my Q here and get correct advice.

I go caravaning and have in the past always used 12volt batteries for running lights,tv,etc kept charged with a 80 watt solar panel.

I know that my 10 inch colour tv @38 watts uses a tad over 3amps when run on 12 volt batteries.I am now going to go on hook-up (mains) for the first time and wish to know if I still work out the amps or part of in the same way for the tv as I would when on 12 volt ie 38 watt divided

12v =3.16 amp.

Would I be correct in dividing the 38 watts by 240volt which gives 0.158 of a amp??? does not seem right to me but ???? please. Many thanks Baz

Reply to
Baz
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In general, you are absolutely correct. It will probably be a little higher than that due to the converter which takes 240v down to the voltages needed by the TV electronics.

Reply to
Palindr☻me

Unfortunately, some converters can be extremely inefficient. For example, I have a cordless phone that uses a 3.6 V NiCd battery. Because it seemed to run warm, I checked the voltage. It was 15.5 V open circuit at the terminals used for charging. Even taking into account that a digital meter might look at peaks of rectified pulses etc, it still seems like a low efficientcy.

Bill

-- Fermez le Bush

Reply to
Salmon Egg

Hi Bill Thanks for your comments and time. Baz

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Reply to
Baz

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