12v TV issues

BigBetty

BigBetty

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Hoping someone with experience can help me.

I have a new 12v smart TV and also brand new leisure batteries x2 with solar.

The TV works perfect on 12v if we are on ehu or the engine is running.
At night with no ehu it flickers and cuts off.

If I put the inverter on and plug it into a 3 pin socket it works fine but this appears to hammer the batteries.

Is my TV faulty?

Thanks
 
I would guess at there's nothing wrong with the TV but the supply of power to it. Is your issue with the batteries?
 
Could it be voltage drop,I had this problem. I fitted heavier gauge wire.
 
Manic said:
Could it be voltage drop,I had this problem. I fitted heavier gauge wire.
Click to expand...
Thanks which wire did you replace? From the battery to the 12v socket?

Would being on charge stop the voltage drop issue?

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Is the tv actually designed to run off 12v? are you connecting via a voltage stabiliser? These will take in battery voltage and send out 12v almost independent of battery state. if you are just taking the raw dc from the motorhome then it sounds as if as soon as the battery voltage starts to fall below say 12.8, then the tv starts to shutdown.
The invertor will have greater losses as it will take 12v dc up to 240 ac then the tv brings it back down to what it like, hence the greater load on the batteries.
Whats the make and model of the tv, was it supplied specially for mh use?

Mike
 
Being on ehu will raise the dc voltage to about 13.8 and sustain the tv ( same as running the engine)

Some tv's do not like 13.8v hence the stabiliser,
Mike
 
Check the output voltage stated on the mains adaptor then check the actual voltage (off hookup) using a meter at the socket.
If the socket is less than the output voltage stated on the mains adaptor that's your problem.
 
A voltage reading at the TV when it starts to misbehave would be my starting point.
 
First thing to try (after checking wiring and the actual voltage at the socket in your MH) is to CUT OFF the usually very cheap and nasty 12V plug you have from the TV - I am assuming you have a cigarette lighter style plug on the TV?
I had a brand new TV that was intermittant but finally discovered the wiring inside the 12V supplied plug was very poor. Bought a replacement and fitted nice and securely - no drop out since (apart from when water pump runs, it flickers but not enough to turn off TV).

e.g.....

Link Removed
 
Thanks for all the responses
Tv was recomended in a thread on here.
Sharp 24" Smart LED TV DVD Caravan Truck Freeview Play Satellite Saorview PVR

I am plugging it into the factory fitted 12v cig lighter style socket. It reaches 2 other 12v sockets so tried it in all 3 and it behaves the same.

Re the voltage stabilizer I don't know what one is but assume if it's needed then CL will have fitted it?

I initially thought it was a bad connection in the plug or socket but it is always fine when driving which would be the worst time if there was a loose connection. I will check the voltage at the socket with no ehu.

If it is low what would be the possible fix / next step?

Thanks
 
Looking up what you have said you have it refers to a 12/24v charger adapter.

"Box contents - Sharp LC-24DHG6132KFM 24" TV with Built-in DVD Player - Feet with screws - Remote control - Batteries - Quick start guide - Manual - 12V / 24V Adapter (in car charger) - UK 3 Pin Plug - "

This could be faulty, also it states that it draws 25watts ie 2 amps. I would begin to wonder if its voltage drop in the wiring to the sockets. Easiest way to check is with a voltmeter into an adjacent 12v socket and see what it is giving you when the tv is on then turn off the ehu and watch it drop.
I wonder did any previous tv work ok?
Mike
 
Mike800966 said:
Looking up what you have said you have it refers to a 12/24v charger adapter.

"Box contents - Sharp LC-24DHG6132KFM 24" TV with Built-in DVD Player - Feet with screws - Remote control - Batteries - Quick start guide - Manual - 12V / 24V Adapter (in car charger) - UK 3 Pin Plug - "

This could be faulty, also it states that it draws 25watts ie 2 amps. I would begin to wonder if its voltage drop in the wiring to the sockets. Easiest way to check is with a voltmeter into an adjacent 12v socket and see what it is giving you when the tv is on then turn off the ehu and watch it drop.
I wonder did any previous tv work ok?
Mike
Click to expand...
Thanks Mike it's in storage for a few weeks while my drive gets done. Will try this when I get it back on the drive. There was crap little tv in it when we got it. It did work on our first trip yes but not for long as the leisure batteries were past it. I replaced them and fitted the new TV at same time.

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BigBetty said:
Thanks which wire did you replace? From the battery to the 12v socket?

Would being on charge stop the voltage drop issue?
Click to expand...
I had put a 12volt twin socket in and found the wire I had used was not big enough.
mine worked ok on EHU.
 
Thats the clue, it was a small tv before, you are drawing more current and the extra load on the wiring is causing the voltage drop.
I would also look at the wiring and the performance of the "new" leisure batteries as well
A simple voltmeter is a very useful tool.
Pity you are so far away
Mike
 
Mike800966 said:
Thats the clue, it was a small tv before, you are drawing more current and the extra load on the wiring is causing the voltage drop.
I would also look at the wiring and the performance of the "new" leisure batteries as well
A simple voltmeter is a very useful tool.
Pity you are so far away
Mike
Click to expand...
Thanks Mike. I have a volt meter. When I get her back on the drive I'll post up my findings cheers
 
Mike800966 said:
Looking up what you have said you have it refers to a 12/24v charger adapter.

"Box contents - Sharp LC-24DHG6132KFM 24" TV with Built-in DVD Player - Feet with screws - Remote control - Batteries - Quick start guide - Manual - 12V / 24V Adapter (in car charger) - UK 3 Pin Plug - "

This could be faulty, also it states that it draws 25watts ie 2 amps. I would begin to wonder if its voltage drop in the wiring to the sockets. Easiest way to check is with a voltmeter into an adjacent 12v socket and see what it is giving you when the tv is on then turn off the ehu and watch it drop.
I wonder did any previous tv work ok?
Mike
Click to expand...
Hi Mike
Ok so just tested this. I think so measuring DC V at a 12v socket with the ehu and the tv and heating few lights on.
I get 13.16 then i disconnect ehu and it drops straight away to 12.4 tv fails then checked again and its 12.1
 
.... then I Re connect ehu and get 12.95 then a few mins later it's back up to 13.16

Not sure if I am measuring correctly or what it tells us?

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What is the voltage measured directly off the leisure battery when it's 12.1 at the TV?
 
The TV is quite intolerant of a bit of a voltage drop isn't it ?
Only thing you can do is run thicker cables and even then you might not have much success.
I'd have thought a TV would work down to 9 or 10v before shutting down? when you say "flickers and cuts off" is that losing signal or switching off?
 
Richard and Ann said:
The TV is quite intolerant of a bit of a voltage drop isn't it ?
Only thing you can do is run thicker cables and even then you might not have much success.
I'd have thought a TV would work down to 9 or 10v before shutting down? when you say "flickers and cuts off" is that losing signal or switching off?
Click to expand...

Well we have mainly been using it to play DVDs when off site as the sat dish I have yet to figure out. But yes the picture starts flickering then it shuts down completely.

So are my readings fairly normal then?

Thanks
 
BigBetty said:
Well we have mainly been using it to play DVDs when off site as the sat dish I have yet to figure out. But yes the picture starts flickering then it shuts down completely.

So are my readings fairly normal then?

Thanks
Click to expand...
Yes half a volt drop shouldn't cause a problem.
What is the output from the power supply that came with the TV? Should say on it.

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Don't know then, it's a strange one.
A few long shots...

Is something big powering up and momentarily dropping the voltage?

Is the plug tight in the cigar socket?

Is the plug warm when you pull it out (especially the contacts)?

TV could be faulty or just a bad design. Same as I said earlier a bigger cable to the battery or doubling up the cable may help.
 
We had exactly the same problem, as soon as 12v is used elsewhere in the van the 12v sockets suffered first. Use a meter when there is no load and the voltage was a steady 12.6, plug something in and we were lucky to get12v. Tv now hard wired to EBL and recorder via inverter, all works fine.
 
the solution is to fit a buck converter with stabilised output into the feed wire to the socket. Any voltage drop in the wire or caused by the pump pulling the voltage down will affect some 12v TVs

the buck converter will increase the input voltage when below 12v and give a stabilised constant 12v output. Simple to install too, just take the 2 wires from the back of the socket and attach to the input and 2 new wires from the output to the socket. One suited to this task is likely the size of a matchbox
 
TheBig1 said:
the solution is to fit a buck converter with stabilised output into the feed wire to the socket. Any voltage drop in the wire or caused by the pump pulling the voltage down will affect some 12v TVs

the buck converter will increase the input voltage when below 12v and give a stabilised constant 12v output. Simple to install too, just take the 2 wires from the back of the socket and attach to the input and 2 new wires from the output to the socket. One suited to this task is likely the size of a matchbox
Click to expand...
Awesome thanks

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