inverter inevitability? (1 Viewer)

imabitcamp

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Nov 24, 2018
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good morrow ladies and gentlemen!

now , I've just fitted a microwave and purchased a " so called" 1500 watt, 3000 peak inverter.
after my initial surprise," Christ it's tiny, I've seen much bigger ones"
I got it all properly connected etc, I then test the damm thing, by means of pathetically attempting to boil an inch of water in a jug.
after twenty mins of gazing through a mesh oven door I finally opened it to still be able to stick my digit in said water.
( my mother in law would be able to raise the temperature higher by just staring at it) .
I know these things DO work, I've been in vans and seen them.
now, more to the point guys.

1. am I right in assuming I'm a Berk for buying Chinese rubbish? ( you get what you pay for) ?
2.it should ideally be a pure Sine wave inverter, of higher quality and real, true performance and size?

I await your replies guys.
all the best , to you all and enjoy the rest of your weekends.
 
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imabitcamp

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ps.
sorry guys, it's only an 800 watt m w.

cheers.
 

funflair

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Is the inverter "pure sine wave" or "modified sine wave" in my experience a "modified or square wave" was useless at running a microwave OK the light came on but that was about it.

So the answer might be a brutal YES, our microwave will boil two mugs of milk in 4 minutes but the Pure sine inverter cost nearly £700.

Martin
 
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imabitcamp

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cheers fellas.
yes I've two big leisure batteries.

I've seen 12 volt microwaves for sale on evilbay for about 120 pounds.
And on inspection they appear to be a standard microwave with an inverter grafted on the back of them.

any views on this dudes?


thanks already though

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funflair

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cheers fellas.
yes I've two big leisure batteries.

I've seen 12 volt microwaves for sale on evilbay for about 120 pounds.
And on inspection they appear to be a standard microwave with an inverter grafted on the back of them.

any views on this dudes?


thanks already though
I wouldn’t ;) get a decent inverter and it will run all sorts of thing, batteries allowing as @SteveandDenise says.

Martin
 
Oct 7, 2015
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I got a 3000/6000 pure sine wave off e bay last year for about £150 works a 800w micro wave no problem I have 2 120 amp batterys
 
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imabitcamp

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hey lofty!
that sounds perfect.
you haven't got the eBay item number have you?

cheers.
 

Khizzie

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Took my microwave out and sold it, hardly ever used it so used the space and weight available for another cupboard... LOL
 
Oct 7, 2015
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hey lofty!
that sounds perfect.
you haven't got the eBay item number have you?

cheers.
Hi cannot find exact but one made by this firm ne thin I did find that improved power was to have both batterys using short leads to inverter ie two lives and two earths, and not relying on the batterys in parallel and one set of leads.
 

scotjimland

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Frankly , if you don't use EHU, a microwave oven is more bother than it's worth.. normal leisure batteries were never designed for heavy loads.. an 800 watt cooking power micro pulls about 85A, that kills them .. for that you need traction or starter batteries..

I've never had one in any motorhome, but fitted one in my caravan simply because nearly all sites now have EHU which is included in the pitch price.. so makes it worth while.

12v microwave, will need heavy cables.. size will depend on run and load.. for example, a 4 mt. cable run with a load of 85A, acceptable loss 2%, would require 70mm cable .. think welding cable size.. :confused:
 
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Lenny HB

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Not only does your inverter need to be a pure sinewave it is also probably too small. A 800 watt microwave will probably draw over 1600 watts on start up, also cheap inverters often trip way before their rated power. You need to fit a decent quality 2000 watt inverter which means spending £600+ also probably need to increase your battery bank if you only have 2 batteries, as Jim says overload the batteries and you will kill them fairly quick.

It's pot luck if a cheap inverter will work or not where as a decent one will give a decent pure sine output, cheap ones the output is not as pure as they claim. I use a cheap one the output is not that good but far better than a modifide sine one, does what I need but if replacing I would spend the extra on a good one.

A lot of the better microwaves have inverter technology and only draw around 30% more power on start up but they tend to be the bigger expensive microwaves.
 
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Lenny HB

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Looks like you have used your 5 free posts new to pay your subs if you want to carry on posting, well worth it.

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Microwave ovens are rated by their output (cooking) power and not by the power taken from the mains or an inverter. An 800W microwave will be taking 1200W - 1500W from the mains. To run comfortably an inverter needs a little headroom so a 2000W inverter will do the job. If the oven has a conventional fan-assisted oven built in that too needs to be taken into account (if you intend to use it).
 
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Frankly , if you don't use EHU, a microwave oven is more bother than it's worth.. normal leisure batteries were never designed for heavy loads.. an 800 watt cooking power micro pulls about 85A, that kills them .. for that you need traction or starter batteries..

I've never had one in any motorhome, but fitted one in my caravan simply because nearly all sites now have EHU which is included in the pitch price.. so makes it worth while.

12v microwave, will need heavy cables.. size will depend on run and load.. for example, a 4 mt. cable run with a load of 85A, acceptable loss 2%, would require 70mm cable .. think welding cable size.. :confused:
But wouldn,t you have to be incredibly stupid not to put the inverter next to the battery (or as near as possible) and just run mains cable
 

scotjimland

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But wouldn,t you have to be incredibly stupid not to put the inverter next to the battery (or as near as possible) and just run mains cable

I think you misunderstood my post..

My post is in reply to the OP who said he was thinking on a 12VDC oven.. not a 240v oven using a 12vdc- 240vac inverter

so the answer is no.. if you have a 12vdc oven it has to be fed with... 12vdc. not 240vac
I've seen 12 volt microwaves for sale on evilbay for about 120 pounds.
 

funflair

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But wouldn,t you have to be incredibly stupid not to put the inverter next to the battery (or as near as possible) and just run mains cable
I can only agree BUT of course there are incredibly stupid people out there, our van had 8 metres of welder cable 70 or 80mm square to the inverter and if it wasn’t voltage drop that stopped it working it was the cheap modified wave, so it all came out and fitted properly and the bonus was I got spare cable for connecting batteries.

Martin
 

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