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Has anyone got some basic information to new comers about invertors please. What are the pros and cons and how does one instal them. Can any one reccomend a manufacture. Are they really cost effective. I am thinking about ruuning my Toshiba Tecra 8000 linked to some GPS software on the passenger side for my wife to navigate.
 

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You asked for basic information?

Well they take in a small dc voltage, usually 12volt to suit our vehicles, and poke out a much larger voltage, usually about 220 - 240 volts alternating at 50 cycles. The more load you want to put on it the more the cost.

However the load is an important consideration with invertors as not all give out a perfect waveform like you would have on a national grid style electrical installation, commonly referred to as 'mains electric'. some are almost square like, others are saw tooth and so on. So before you shell out, do tell the supplier what you intend to run on it, as some invertors will damage the equipment plugged in to it. Cheap is not always best with invertors

If your only running inductive loads, there’s not a lot to worry about, however not strictly in that category, I do run the mobile charger and the power supply to my laptop off mine.
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Averywildwildcamper said:
.........as some invertors will damage the equipment plugged in to it. Cheap is not always best with invertors
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We wish we'd had your advice before we bought ours.
It did for the toothbrush charger with us.

Gillian
 

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Steve, couldnt you put a 'choke' inline with the inverter to smooth out the wave? I think I know what Im talking about :dontknow:
 

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You could add a choke, but ideally you need a scope to check on your results, but invertors are so cheap these days its not worth the hassle, besides experimenting with your new inverter before the warranty is out, isn't recommended.

I still think its best to shop around for the appropriate capacity unit and check its the supplier that their model is suitable, then if something happens the onus is back to them.
 

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Cheap Invertors

I recently purchased a Belkin 300 watt invertor primarily to power the portable colour TV, charge up the laptop etc. The manufacturer's literature said it was fine for these uses but when I used the TV the picture had a green hue across the top of the screen.
I checked both the battery input and the invertor output voltage with a digital multimeter, all was ok. I tried other mains accessories and they were fine.
As this invertor produces a modified wave I can only assume that the TV doesn't like it :cry: I spoke to the dealer who said that some TVs were more suseptable to modified sine waves than others.
It got me thinking, what if it damaged other electronic devices such as the laptop or DVD
Guess what I'm buying now !! ...an invertor with a true sine wave output. Yes, it's a lot more expensive but for peace of mind it's worth it.

Has anyone else had problems with cheap invertors ? This one cost around £50 and as far as I'm concerned it was a waste of money.

Jim
 

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I run a 600w cheapie with no problems and use it for my laptop, I admit I get the occasional line across the TV screen but it does no worry me. As for the colour tinge on your screen Jim that sounds more like a magnetic influence and is typical of the degauser not working correctly on startup, from my limited knowlege of the matter I would not have thought it would be the modifide sine wave doing it but more likly to be the extra surge needed for the degauser, hence my reason for useing a 600W.

There must be a TV engineer out there that knows the answer?

Ken S.
 

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Thanks for the input Ken,
it sounds quite possible that it is the degauser that isn't working properly on start up , I never thought of that, but it still begs the question why a manufacturer of invertors can say that their product will operate up to a 19 in TV, (mine is a 14 in and is rated at 45 watts. ) when it obviously doesn't take into account of the high surge on initial start up and fails to degause properly.
Your advice about buying a 600 watt unit is good advice for anyone contemplating buying a unit and using a TV.
Before I posted here I had already sent off for a 600 watt true sine wave unit which I don't regret as I think in the long term will be safer for delicate electronics and give better performance.
Anyone want to buy a 300 watt invertor, one careful owner, little used .?? .... lol

Jim :D
 

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All good advice above.

We started our 'flirting' with inverters by trying a couple of from Maplin. The first one we bought was a 100W 'modified sine wave'. Now although that sounds better than a 'pure sine wave', it isn't! In truth the output's never seen a sine wave, let alone been modified from one! It blew up BOTH of our toothbrush chargers, and overheated trying to recharge our walkie-talkies.

The seond one we bought was a 100W sine wave version, a LOT more expensive but didn't blow anything up. Anyway, we needed more juice for our desktop PC so returned it and went for a 300W Mobitronic sine wave inverter (we sell them on our shop)

We've had NO problems at all with that unit, it's usually very quiet (some load types make a bit of a hum) It's been reliable and is a good German build.

Another thing to watch out for is the continuous load compared with the surge capacity (the Mobitronic is 300W / 600W) A large surge capacity allows item (like fridges) to startup without overloading the inverter. Most are overload protected these days.

Another bit of advice is that inverters run at their most efficient at about 1/3 of their stated continuous load.

Hope this helps
 

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Inverters - problems, problems!

:?: Having weighed up the pro's and cons we eventually decided that an inverter would be the best way of powering our new 15" Sharp flat screen TV.
We bought a Nikkai 600w modified sine wave inverter costing a very reasonable £40+ from Maplins. We were assured that it was more than capable of running not only the TV but also a digibox and a camcorder recharger.
We wired it up to our twin battery set up for a quick test but found to our dismay that it didn't work!
It produced a clicking sound from the TV transformer (240v to 12V) and produced nothing but a blank screen. There was a similar reaction from the camcorder recharger unit which also resulted in a pulsing red light on the camera itself (its normally a steady red light for 3 seconds or so before turning to green to show its charging up)
Luckily there appears to be no damage to either unit. :(
Before we return the inverter, I'm wondering whether its the modified sine wave thats causing the problem? Any ideas anybody?
 

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We have a 15" Sharp flatscreen also. It runs perfectly on a Moore 300watt modified sine wave inverter. Your 600 watt Maplin must be faulty. Moore inverters are expensive but from speaking to people they always seem to deliver.
 

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I run my Sharp 15" Aquuos LCD from a cheap 150w inverter, never a problem.

Still beats me that this is a 12v TV and there is not available a lead we could just plug into the 12v suppply! Seems Sharp are missing out here. Surely there must be somebody who can produce a lead for these popular TVs?

John 8)
 

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Hi

Buy modified sine wave and it as a few limitations very few but here they are.

It cannot run the toothbrushes, It cannot run Automatic washing machines due to (thyristors) It doesnt like Combined TV Videos (thyristors in the joint power supply)

Occasionally the no name brands version of modified sine wave is bad far nearer to square wave.

I have run the following all from modified Sine wave invertors with no problems(Good brand Sterling, not that dear either)

Fridge full size domestic

Microwaves 3

Heaters (just testing)

Hot water Truma Boiler

HairDryer

Computers several

Chargers many NOT toothbrush

TV 17 " Flatscreen LCD

DVD Player

Paystation 1 and 2

Printers

Fax

There are several ways around the toothbrush Charger charge when hooked up, buy a small Pure sine invertor.

Pure sine wave should be you last resort for several reasons in general use they cost you far more ah (ie batteries flatter quicker) Expensive if they are not the only answer.

Your motto should always be

Modified (Quasi sine) wave first Choice.

Pure sine wave LAST resort.
 

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BTW I have recently tested the Cheap Nikkai Invertors from Maplins


150W £14.99
300w £19.99
600w £39.99

Checked most of the above items and again no problems. Now in the last 3 days have had to buy 7 for friends and family!

All definately work OK with sterling Quasi sine wave.
 

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GeorgeTelford said:
Hi

Buy modified sine wave and it as a few limitations very few but here they are.

It cannot run the toothbrushes, It cannot run Automatic washing machines due to (thyristors) It doesnt like Combined TV Videos (thyristors in the joint power supply)

Strewth George, have you got an Automatic washing machine in your MH? You must have a large inverter they take about 3Kw.

All the best,

John
 

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Hi

No no big auto washer in mine, but it is done in some Yatchs and motorhomes.

George
 

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Jabber.

It is not just a question of a lead to enable a Sharp Aquos to run on 12 volts. I e mailed Sharp on this point some time ago and they informed me that, because of fluctuations in voltage in motorhomes, their particular TVs need to be run through an inverter.

G
 

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Hi!

Averywildwildcamper said:
...If your only running inductive loads, there's not a lot to worry about...
I think you wanted to say "non-inductive loads" here... :wink:

I have a cheap (Taiwan-made) 150 W inverter. It says "modified sine wave", but I haven't checked that with a 'scope yet. (Strange, I actually own an oscilloscope but have not yet thought of it... Will do next days.) So far I have tested it with:

- Laptops (Compaq, Dell and HP, but no Siemens)
- Charger for electric shaver (Braun)
- Mobile phone chargers (Siemens, Nokia, Panasonic, Samsung)
- Digicam (still photo) chargers (Sanyo)
- Portable cassette player (Sony kids version)

No problems occured so far. Except that on hot summer days the inverter goes on overheat with the laptop. And with the cassette player there was an audible hum on the speaker.

Don't know why but it seems that especially toothbrush chargers are sensitive. And I have heard several reports about Siemens laptop power supplies not working on modified sine.

Best Regards,
Gerhard
 
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