12V to 240v inverters

[123hotchef]

what kind of size will I need to charge 18V batteries? is it worth getting the biggest I can afford just incase I want to boil the kettle LOL. yes I know I dont really want to boil a kettle but you know you never know

 

[wookie]

The problem with inverters is efficiency, they are fairly efficient at the higher end of their power rating (think 90%) but tend to be terribly inefficient at low outputs.

So if you have a big inverter but only really use it at a 1/10th of its rated output you'll be sucking plenty of Ah from your battery for very little AC, where as a much small inverter providing the same amount of AC will draw a lot less DC Ah from your battery.

 

[123hotchef]

I have a wee one in the loft 250W or something i need to dig it out and check the chargers

 

[Revs1972]

What brand of batteries are you charging ?

 

[chevy2]

I used to carry one in the van to charge batteries, approx 300 watts?
Worked ok on the makita 18v ni/mh charger but kept tripping when i changed over to 18v l/ion batteries n charger,
I reckon about 500w would about the min to cope with the modern 18v fast chargers?

 

[rikrobson]

what is the rating on the charger you want to use? A 600W inverter should do it, but you'll not run much else. A 1200W would be more versatile.

 

[123hotchef]

I have a few different battery types 12V LI 14.4V NiCad

I will did my wee one out and give it a bash before I invest in a big boy.

Any brands to avoid or go for?

 

[julianf]

Those blue IMAX chargers that are all over eBay will run from a DC source.

They are highly configurable, and, if you can devise a configuration for your chosen batteries, then that seems a simpler, cheaper, more efficient option.

Check the input requirements though - I don't own one, so it may be that you need headroom on the input side - I just don't know.


(a friend was using one at the weekend, so I got a brief introduction to them)

 

[123hotchef]

these are cheap http://www.ebay.co.uk/itm/1500W-Aut...id=100033&rk=4&rkt=8&mehot=pp&sd=272743738493

 

[julianf]

cheaper than the charger i was on about - i think my friend said it was about £40 (there are clones cheaper, but they have poor longevity - im told!)

 

[Kayos]

these are cheap http://www.ebay.co.uk/itm/1500W-Auto-Inverter-Car-DC-12V-to-AC-220V-Modified-Power-Converter-Sine-Wave/151913411890?_trksid=p2045573.c100033.m2042&_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=43782&meid=94d53360b4d648d8af4f9fb014eff0d6&pid=100033&rk=4&rkt=8&mehot=pp&sd=272743738493

Love the mains socket on them, I reboxed my old one so I could have a proper 13a socket

 

[123hotchef]

2000W a few quid more http://www.ebay.co.uk/itm/2000W-Pow...id=100005&rk=1&rkt=6&mehot=pp&sd=232324090759

 

[Shox Dr]

these are cheap http://www.ebay.co.uk/itm/1500W-Auto-Inverter-Car-DC-12V-to-AC-220V-Modified-Power-Converter-Sine-Wave/151913411890?_trksid=p2045573.c100033.m2042&_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=43782&meid=94d53360b4d648d8af4f9fb014eff0d6&pid=100033&rk=4&rkt=8&mehot=pp&sd=272743738493

Can they be used for long periods

 

[123hotchef]

Can they be used for long periods

read the small print 2000w is bull carp

Continues AC Output Power: 800W
● 30-minute AC Output Power: 700W
● Maximum AC Output Power: 1600W

 

[henry Kadzielski]

what kind of size will I need to charge 18V batteries? is it worth getting the biggest I can afford just incase I want to boil the kettle LOL. yes I know I dont really want to boil a kettle but you know you never know

Good morning 123hotchef.
To boil a kettle on a 12v to 240v invertor is a scary proposition. A normal kettle here in Au is between 1600w to 2000w at 240v. So assuming 100% efficiency (just for arguments sake)
P=IV
2000=I*12 so
I (current)=2000/12
1=166.6amps

That means you will require significant welding leeds from the battery to power the invertor plus the 12v battery will need to be 'QUITE' big.
I have a invertor setup in my service truck. 2000w with 50% overload. This will boil a kettle but boy does it knock the batteries about. The truck when not connected to mains has it's aux batteries charged through solar panels of which I have 6 total about 1200w in good direct sunlight. Be carefull what you ask for it will get expensive

 

[123hotchef]

Good morning 123hotchef.
To boil a kettle on a 12v to 240v invertor is a scary proposition. A normal kettle here in Au is between 1600w to 2000w at 240v. So assuming 100% efficiency (just for arguments sake)
P=IV
2000=I*12 so
I (current)=2000/12
1=166.6amps

That means you will require significant welding leeds from the battery to power the invertor plus the 12v battery will need to be 'QUITE' big.
I have a invertor setup in my service truck. 2000w with 50% overload. This will boil a kettle but boy does it knock the batteries about. The truck when not connected to mains has it's aux batteries charged through solar panels of which I have 6 total about 1200w in good direct sunlight. Be carefull what you ask for it will get expensive

Good morning or good evening for you mate,

I was not wanting to boil a kettle honestly but maybe in a real emergency use a angle grinder perhaps!
Looking at the cheap inverters they can only be used for 30mins at a time.

I brought one in NZ years ago and still have it but it is only a baby one.

 

[Robotstar5]

As we're discussing kettles , we have a low wattage (about 900W) camping kettle at the off-grid stables, it's only a back up for the gas ring powered one but will run off the generator or inverter, can't be without a cup of tea/coffee

 

[123hotchef]

As we're discussing kettles , we have a low wattage (about 900W) camping kettle at the off-grid stables, it's only a back up for the gas ring powered one but will run off the generator or inverter, can't be without a cup of tea/coffee

cold coffee is just fine lol! that is what the camping cooker is for

 

[123hotchef]

is that the small travel size kettle that takes ages to boil

 

[Robotstar5]

cold coffee is just fine lol! that is what the camping cooker is for

I'd rather drink cold tea than coffee.

is that the small travel size kettle that takes ages to boil

Yes, but it's only a back up in case we run out of gas for the 2 ring camping stove that we normally use. There is even a small microwave oven to run off the genny, Mrs Robo can be there 8-9 hours on a Sunday so at least I get chance to "play" in the garage if I haven't been drafted into doing jobs at the stables.