David Lock

Please bear in mind this is from "Electrically Challenged" of West Sussex

We still have a few power cuts around here and it's nice to have a bit of power to keep going. I keep wondering about getting a genset as the smaller ones are cheap as chips now.

But....... if I got a mains inverter I guess I could run it off the car battery but would I be able to keep car engine running to keep the battery charged as it provided the power source for the inverter?

I assume I couldn't take too much power as it would just overwhelm the car's charging system.

So is this feasible or just bolloxs please?

I would plan to plug it directly to the battery of a 1.9 TD engine.

Here are the sort of things I am talking about.

http://www.mdsbattery.co.uk/departme...partmentID=113

Thanks, dl

kingofturds

iTrader: (1)

£184 for a 2.5kw inverter Have you considered buying a generator?
I got a 2nd hand 2.5 kw generator for 80 quid but you can buy them new for around 200 much less trouble

David Lock

I did have a second hand gen set which I bought when I used to hire out marquees and some customers wanted a power source. But it was bloody heavy to haul about, pull start and hard work!! The small power inverters are pretty cheap which is why I asked about them. Also no worries about knocking holes in garage wall for exhaust pipes. dl

kingofturds

iTrader: (1)

what sort of equipment are you planning on running on it ?(how many watts) you have a diesel which will have a heavy duty battery. I used to have a 500w inverter and that thing sucked the life out of the battery of my diesel laguna.

David Lock

Probably 1500w max. Mostly to keep my pond filter going in summer if it's hot and a few lights if needed. No real power stuff like kettles. Did you keep the Laguna engine running? - that is my main question. Thanks, dl

andy97

iTrader: (1)

1500watts is equivalent to 125Amps/hour. What is your alternator rated at?

You would need to run the car engine, even a diesel battery arent rated that high a current.

kingofturds

iTrader: (1)

When camping yes never had any problems but you could here the tone of the engine change. Engine off however it would suck the battery dry in 30 minutes. I assumed you were wanting it for home use that's why I suggested a cheap generator

David Lock

Thanks guy. Will be seeing my garage mate in a few days so I will see what he thinks (he has just bought a 5.5kw gen for £600). Yes for home use. dl

AndyC_772

iTrader: (2)

There's nothing about hours - to draw 1500W from a 12V source, an inverter would have to pull a minimum of 125A, continuously.

It's actually quite an interesting problem if you're into electronics, though. For example, a resistance in the cable between inverter and battery of just 0.1 Ohms would mean you actually get 750W of useful power, and another 750W lost as heat in the cables. Hope you like the smell of burning plastic and have a fire extinguisher handy

You're talking about an amount of power about the same as the starter motor draws when cranking over the engine. Even if the inverter really can handle that much current, I wouldn't be cheerfully clamping its leads to the battery with alligator clips - chances are you'll never get them off again as they'll be spot welded in place!