Inverter for TV ,notebook.

I need an inverter for TV, computer ,12 volt to 240 volt
.I have been told to buy 1500 watt inverter, the prices of them differ I am not sure what I need. any advice out there.
Thankyou Broometime.
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Reply By: rooster350 - Saturday, Aug 30, 2014 at 10:14

Saturday, Aug 30, 2014 at 10:14
1000w should be plenty to run those 2 things, computer does not use much and it depends on the size of the tv as to how much it uses..a 42 inch lcd uses around 120w
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Reply By: Member - John and Val - Saturday, Aug 30, 2014 at 10:21

Saturday, Aug 30, 2014 at 10:21
Hi,

Rather than buying an inverter to provide 240V from your 12V, suggest it's far better to buy a 12V power supply for the laptop. If the tv has an external power supply, replacing that with a 12V one would be the way to go too. Have a look at the rating plate on the laptop supply - it will tell you it's output voltage (probably about 17, 18 or 19V) and also its current rating (probably 3 or 4 amps). On ebay you'll almost certainly find lots of suitable power supplies - if you don't like ebay, at least use it as a catalogue!

If the tv has an external supply, same thing applies. If it does not have an external supply then a 240V inverter is one way to go, though getting a 12V compatible tv may be a better (and maybe cheaper) option.

If you do finish up buying an inverter, it should be a pure sine wave one, and NOT a (much cheaper) square wave or "modified" sine wave one. These generate a lot of interference and are not good for sensitive electronics, especially the laptop. You do NOT need a 1500W one for a tv or laptop - 150W is ample.

You may find Electricity for Camping a useful read.

Cheers

John
J and V
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Follow Up By: baznpud (tassie) - Saturday, Aug 30, 2014 at 10:29

Saturday, Aug 30, 2014 at 10:29
Agree with above, we run a tv and laptop off the 400w one in our van, and it's more than enough.
baz
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Follow Up By: Freshstart - Saturday, Aug 30, 2014 at 10:29

Saturday, Aug 30, 2014 at 10:29
Agree with John. We don't use our inverter any more. Only had it for the laptop. Purchased a 12V cigarette lighter type lead for the laptop from ebay for about $22.

But we don't have a TV. Everything now runs off 12V and we have plenty of USB outlets for charging as well.
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Follow Up By: Member - geoffqld - Monday, Sep 01, 2014 at 05:48

Monday, Sep 01, 2014 at 05:48
I use a 300watt pure sine wave inverter and that runs my tv, charges my computer, phone, kindle etc. It also runs my 2 x11watt fluros and will run my Cpap with humidifier. Works well for us.
Geoff
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Follow Up By: Freshstart - Monday, Sep 01, 2014 at 08:48

Monday, Sep 01, 2014 at 08:48
I forgot one important point. Doing it all in 12V gets rid of the problems that some people have with the grounding with 240V AC.
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Reply By: Member - Bruce C (NSW) - Saturday, Aug 30, 2014 at 10:24

Saturday, Aug 30, 2014 at 10:24
Hi Broometime,

You say you need it for the TV and computer.

Is the computer a laptop?.
if so you can get a 12 volt power supply which plugs into a cig socket for the laptop.
That is better than using an inverter as, using an inverter you will be using at least 2 devices which cause losses. The first is the inverter the second will be the transformer which will reduce the inverters 240 back to 19 volts or whatever the laptop is.

This is the one I have

I also have a 12 volt TV which I bought for around $140 dollars. All this is more efficient and cheaper than a good inverter, unless you want the inverter for other jobs as well, then that is another matter of course.

Hope this is helpful.
Cheers, Bruce.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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Follow Up By: Member - Bruce C (NSW) - Saturday, Aug 30, 2014 at 10:37

Saturday, Aug 30, 2014 at 10:37
Yep, heading says notebook.
I must be blind or something. LOL.

Cheers, Bruce.
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restless and lost on a track that I know. HL.

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Follow Up By: broometime - Saturday, Aug 30, 2014 at 15:07

Saturday, Aug 30, 2014 at 15:07
Thanks everyone for all the helpful information.
Cheers Broometime.
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Follow Up By: craigandej - Sunday, Aug 31, 2014 at 14:46

Sunday, Aug 31, 2014 at 14:46
Hi Bruce,

With your laptop power adaptor, can it be set to 19V? Also is the amperage 3.5 at all voltages? I cant find any details of the adaptor on Projecta's website.

Thanks
Craig
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Follow Up By: Member - Bruce C (NSW) - Sunday, Aug 31, 2014 at 16:27

Sunday, Aug 31, 2014 at 16:27
Hi Craigandej,

Yes it can be set to 19 volt and in fact has several voltage settings which are easily set by the user on the back of the unit.

The user selectable voltage settings are as follows.

15V 16V 18V 19V 20V 22V 24V all at 3.5 amps.

I have been using it for around 3 years now with no problems whatsoever.

Cheers, Bruce.
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Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 31, 2014 at 17:03

Sunday, Aug 31, 2014 at 17:03
Bruce, as you would realise, the big advantage of a universal charger with selectable voltages is that it can always accommodate a computer upgrade.
Cheers
Allan

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Follow Up By: Member - Bruce C (NSW) - Sunday, Aug 31, 2014 at 19:06

Sunday, Aug 31, 2014 at 19:06
I hadn’t thought of upgrading Allan but of course you are right.
A simple problem requires a simple solution does it not.

Totally agree with your comments further down, and John and Val’s comments also.

Cheers, Bruce.
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Reply By: Member - Boobook - Saturday, Aug 30, 2014 at 16:02

Saturday, Aug 30, 2014 at 16:02
All of those answers and none offer the correct advice to offer a solution that will definitely do what you are asking. This forum is good for telling you answers based on poster's solutions, even if they have little to do with the original question. Doh.

Firstly do you already have the TV? If not and you are ok with a small one then John and Val is on the money. Get a 12V capable one. For the Laptop you can get 12V converters but they are often expensive and may not work if you get a new PC.

If you want to use a 240V TV or can't get a 12V one in the size you want, and your existing computer 240V adapter then you need an Inverter and you have to start with their power use.

Look up the power use in 'watts' on both the TV and Computer.
If you don't ever want to use the PC and TV together, use the which ever power rating is highest and add 15 - 20%. Eg if your TV is 500W and your laptop is 100W then use 500W, add 20% ( 600W) and that is the minimum size inverter you need.

If you want to use both at the same time then add them up, and add 20%. So 720W is the minimum you need to run both at the same time.

Next you need to decide on a modified Square wave ( often marketed as Modified Sine wave) or true Sine wave. Modified ones are smaller and cheaper but may not work with all electronic devices. Laptop power supplies and TV's are very sensitive.

I would advise a true sine wave. The higher the power, the more expensive, so you can't just randomly pick say 1500W. It'll cost a ton and be huge.

Next you need to determine if you have enough battery power. Divide the number of actual watts by about 10 to get your approx amps. So if you do use 1500W of TV and Computer, that is about 150Amps. That'll drain a 100AH battery flat in 20 minutes to try to get high efficiency devices.

I think most newish small TV's ( 18 to 28 inch) will be 80 - 150W depending on size efficiency and most laptop power supplies are 60 - 100 watts.

Hope this helps.





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Follow Up By: Member - John and Val - Sunday, Aug 31, 2014 at 08:09

Sunday, Aug 31, 2014 at 08:09
"All of those answers and none offer the correct advice to offer a solution that will definitely do what you are asking. This forum is good for telling you answers based on poster's solutions, even if they have little to do with the original question. Doh."

That's a bit sour Boobook!! Yes - you did get trounced a bit on the other thread, but no need to let off steam here! You are one of the more highly respected members of the EO community - lets keep it that way!

We don't know enough about the original poster's requirements or his electricity supply to offer specific suggestions. Is the PC a full size one from home? A laptop? A tablet? Is the tv a little portable? Is it cinema sized? Does he have the battery capacity to handle a big inverter anyway? (He probably isn't aware that if the proposed 1500W one is fully loaded it will draw as much current as the vehicle's starter motor!)

But we can make general recommendations like avoiding inverters by using 12V power supplies where possible. And for sensitive gear like PCs and TVs we can recommend avoiding switchmode devices such as square wave inverters and "modified" sine wave ones (have you seen the waveform supplied by these?)

While I have no argument with your maths, I do hope the OP doesn't gain the impression that it's ok to draw hundreds of watts, hour after hour, without considering his battery capacity and recharging capability.

Fortunately the power ratings printed on power supplies indicate their maximum capacity, and not the continuous power drain of the device they are powering. Typically, after an initial starting surge a small laptop or tv will only draw around 2 or 3 amps at 12V.

I think we've done pretty well and I certainly wouldn't change anything I've said.

Cheers

John

J and V
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Follow Up By: Member - John and Val - Sunday, Aug 31, 2014 at 08:13

Sunday, Aug 31, 2014 at 08:13
Oooops.... I missed it too Bruce - the pc is a notebook. Definitely a candidate for a little (<$30) 12 volt power supply.

Cheers

John
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Follow Up By: Member - Boobook - Sunday, Aug 31, 2014 at 08:53

Sunday, Aug 31, 2014 at 08:53
John

My post referred to how everyone made assumptions, about the users needs. For example in your case that he doesn't already own the TV and can buy a new one.

Also did you read my post or blast in and answer as usual?

how on earth can this part of my post "Next you need to determine if you have enough battery power. Divide the number of actual watts by about 10 to get your approx amps. So if you do use 1500W of TV and Computer, that is about 150Amps. That'll drain a 100AH battery flat in 20 minutes to try to get high efficiency devices."

lead to this observation

"While I have no argument with your maths, I do hope the OP doesn't gain the impression that it's ok to draw hundreds of watts, hour after hour, without considering his battery capacity and recharging capability."

I advise that you read the posts that you respond to first. You seem to have a habit of shooting first.
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Reply By: Member Andys Adventures - Saturday, Aug 30, 2014 at 17:48

Saturday, Aug 30, 2014 at 17:48
Hi Broometime, I think you will find all LCD LED TVs are 12 Volt. They all come with transformers for 240V. I just bought a LED-LCD tv and made a connection to suit the tv and connected it to a 12v battery. As for the note book you can get a cable that will plug into a cig lighter and charge it.
Cheers Andy

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Reply By: Motherhen - Saturday, Aug 30, 2014 at 22:13

Saturday, Aug 30, 2014 at 22:13
Hi Broometime

The television we purchased (a cheapie from eBay) runs direct from 12 v. My husband just removed the converter and wired it in. After running my laptop from an inverter, when it died while travelling, I received the best advice from members here to purchase the 12 v power supply. I now have one which cost $12 from DealExtreme in Hong Kong.

1500 inverter is a big beast, and overkill from small appliances.


Motherhen

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Follow Up By: Motherhen - Saturday, Aug 30, 2014 at 22:14

Saturday, Aug 30, 2014 at 22:14
Times like these a ten minute edit function would be wonderful.

1500 inverter is a big beast, and overkill FOR small appliances.
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Follow Up By: broometime - Sunday, Aug 31, 2014 at 11:53

Sunday, Aug 31, 2014 at 11:53
I have a 28inch 240 volt TV and a laptop that I wish to run when off road a few days at a time. My van has 2 x 105ah Full River batteries and 120watt solar panel, led lights ,fridge on gas. Thanks for all the helpful info , just have to decide maybe go pure sine 300 watt inverter $120 or new 12volt 28in TV round $300 and 12volt cord for lap top.
thanks broometime.
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Reply By: Allan B (Member, SunCoast) - Sunday, Aug 31, 2014 at 14:37

Sunday, Aug 31, 2014 at 14:37
Hi Broometime,

No maths, just advice..............

Forget the inverter, get a new 12 volt LED TV and a 12v universal power supply for the laptop.

Your existing 240v TV will probably draw twice the power of a current 12v LED model and eliminating the inverter will also improve the power efficiency. Also, inverters can be problematic and introduce interference to the TV.

Bear in mind that the larger the TV, the more current it will draw so get the smallest acceptable size. Typically, 19"=30W, 28"=40W. They can be bought for less than $200.
Cheers
Allan

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Reply By: Member - geoffqld - Monday, Sep 01, 2014 at 06:00

Monday, Sep 01, 2014 at 06:00
We found that the wiring of our caravan 12v, from external, was too light for our load, particularly running the 8 amp cpap overnight. It would soon load down the voltage and the low voltage cutout on the cpap would operate, I reckon the cpap would be equal to the 28" tv. The way we got around it is to use the inverter at the batteries in the ute and run an extension cable to the ac input to the caravan. Works very well, never had a problem, just had to turn off the microwave at its power switch to reduce the current draw.
Geoff
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