Ever seen those cheap Chinese generators that you often see at car boot sales?

You know, those "6500W" 3-phase generators with an name resembling a cross between processed cheese and an 80's German techno band? The ones that some people buy without realising what "3-phase" means? (other than it has a volt meter that goes up to 450V AC and sockets that don't fit 13A UK plugs?)
Well, I bought this one brand new for £150 and he even delivered it to my house from the car boot sale. He drove off, thinking, "Tank god I got rida dat ting, so I did!" - (yes he was Irish).
But I had a cunning plan...
Remember these?

I've been playing with backup generators for a while. Starting with this one:

The generic Chinese 650W single phase, 2-stroke smoker. £35 from a car boot with free grass in the fuel filter.
It kinda worked with one of the chargers but that wasn't enough, although the fumigation of the neighbourhood was.
So I sold that at a car boot (for £50, minus the grass in the fuel filter) and got one of these:

It was a bit better. Even more noisy but being a 4-stroke engine, easier to start and largely smoke-free. Still only good for running one charger. So I sold that and bought the soft cheese techno generator.
With three extension cables and some adapter plugs, each phase can run a charger at 15A (400W) for a total charge rate of 1.2kW. The thing will run the chargers at up to 20A each (540W / 1.6kW) but it's prone to cutting out after about 30 minutes. At 1.2kW it seems happy to run continuously.
The latest in 2016 spreadable dairy synth electricity looks like this:



Quite a lot of 16.6kHz ripple from the (digital?) AVR.
But with a EMI filter on each extension lead, you get rid of the ripple and are just left with a 50Hz triangle wave. Close enough to a sine wave to not start a fire, I guess.


Beats the gnarly SIP generator waveform...

The harmonics on that couldn't be filtered and almost cooked an energy monitor that I was using. I sold it to an Irishman and as he drove off I thought, in my best Japanese, "Kamisama! Nuguushimashita... Aaa, yokatta, yokatta!" (God! I got rid of it. Thank goodness!)
So now I can actually charge my house battery at night, in a power cut. It still requires ear defenders and, at 1.2kW, it will still take 16 hours to fully recharge the battery. But should the occasion arise, the neighbours will be in no doubt that I have electricity and they don't.
