That is exactly why there are regulations.
Yes. Your generatorās case will float in the middle, at around 115V relative to ground, because one leg (the one you tied to neutral) is now tied to the earth of the house (which is a very good earth), but the middle of the winding is tied to your generator case. So it will work, but nobody can touch the generatorā¦
Some people will couple such a device to the house, without a TN bond. Everything is still earthed, but earth and neutral is not at the same potential and your earth leakage equipment now doesnāt work properly.
Thatās why there are regulations.
Great, makes sense!
Besides an unknown earth-loop impedance that will throw the earth leakage a wobbler.
A neutral-to-earth fault can produce a short, and the MCBs that are rated to protect the house wiring are only in the conventional live wire.
It is also the convention to only switch the live in a plug socket, not the (now live) neutral, which means something that is switched off can still shock.
So you may or may not have working earth-leakage protection, and you definitely wonāt have adequate overload protection for certain faults.
Basically, an all-around bad idea.
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Thanks Phil, yes, that makes sense.
I know what to look for now.
Bundupower has a few FAW, diesel, 1500rpm, 4 pole generators.
and also LPG gas generators. They are 3000rpm, 2 pole, so probably less idealā¦but smaller and quieterā¦ Do you know if they are centre tapped? Bundu Power says they are inverter friendly.
In the absence of an explicit statement:
The only way to be sure is to test with a voltmeter.
Bad signs are wheels, suitcase types and plug sockets without an earth leakage unit.
Good signs are noise suppression measures and looking like it is a fixed unit and earth leakage protection for any plug socket or having no plug sockets at all.
Iād be 99.9% sure both those generators in your links are the correct type.
Your usage pattern can influence your fuel choice:
LPG has an indefinite shelf life.
Diesel can only be stored for 6-12 months.
LPG is a different animal, 3000RPM is fine.
The reason I harp a bit on 1500RPM, is because thatās optimum for a Diesel engine (trucks/lorries have their red line at 2500RPM for example), and the slower engine speed means less wear and tear on the engine. You can run a Diesel at 3000RPM, but it is not optimal. Petrol engines, on the other hand, have power and torque curves crossing around 4200RPM, so they run better at the higher RPMs. I think LPG is going to be similar, and as Phil said, it has other advantages as well.
There was a similar question on the Victron Energy facebook group this morning, with several people vouching for LPG (or natural gas, if you have it).
Thanks, Izak. That makes my decision much easier.
I think this is what I am going to get:
Generac 8.8KVA LPG gas generator
It is relatively quiet (62db), relatively light (175kg) and compact for the power.
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Please report back!
I was going to get one of the bigger ones for our Callcentre, but then Covidā¦
We were on the second floor and there was already central gas to the restaurants in the courtyard. Pretty sure it wouldāve worked great 
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I also am a LPG generator fan although have never used it to supplement my solar and batteriesā¦yet ! Other benefits of LPG gennies are:-
- As the engine does not use petrol, the carburetors cannot gum up and no blocked jets from dirty petrol. Also there is no ethanol in LPG to corrode components.
- Is quieter than a petrol generator.
- Exhaust gas from burning LPG has less noxious chemicals and thus there is less stink when running it.
- LPG does not degrade. Yes petrol in the gennies tank or storage container goes vrot !
One drawback of a LPG generator is that the same engine produces less power on LPG vs running it on petrol.
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@Phil.g00
Your idea on using DC into a MPPT to charge batteries got me thinkingā¦ 
How about using a normal/smelly/petrol/generator with ugly AC waveform output to feed a (large) step-down transformer with sufficiently rated rectifiers and smoothing capacitors and feed that smooth DC to the MPPT controller to charge the batteries. The Victron MPPT can then feed information to Venus to get accurate charge data.
Yes one would need a transformer of sufficient capacity plus most likely would need some inrush current protection as there will be a large surge current at start-up to charge the smoothing capacitors.
That is essentially what a wind turbine provides rectified 3ph, albeit at a higher frequency than 50Hz. ( excluding axial flux types)
The 50Hz from a standard generator may pose an issue; it would certainly have to be 3 phase at least, I think.
Obviously, the more sign waves (phases), the smoother the resultant DC when rectified.
(less ripple and less work for a smoothing capacitor).
These 96V DC generators are sold as EV distance extenders in China.
I have seen them advertised as having 27 poles.
Now, hereās what I donāt know for a fact, so I am guessing.
I think that means it is 9 ph AC before it is rectified, so that means so seriously smooth DC after rectification, (sort of like an axial flux generator, or maybe it is one).
( Caveat: if I am guessing correctly).
EdIt: I thought about it, and could very well be an axial flux generator.
Here is an informative link. Note the permanent magnets spin (they are set in the blue disc) with the Lister flywheel and you can have a stationery winding ( set in the grey resin disc) on each side of the spinning magnets. In this video he doesnāt take advantage of this with a winding only on the inside of the blue disc.
The Outback device is an MPPT.
One of the inverter generators could also be a good option - it has a 3 phase output, so less smoothing is required (and will have all the components to do so inside). If you can find an MPPT that can handle the output voltage (and is compatible with a wind generator), you should be able to wire it in directly. Then the only remaining issue is overriding the motor speed control, but that should be easy.
I assume you mean the DC that the inverter generator generates before going to the inverter.
This would be good and (if it indeed is 3 phase as you mention) then it sure would make rectification easier to smooth vs single phase. The permanent magnet/coil arrangement as shown in the Listeroid link above would work no doubt (there was a chap in UK who published plans on casting your magnets in fibreglass and winding your own coils) but this is too much of an effort ! Can someone confirm the DC voltage from a typical generator and if it is 3 phase ?
I guess one would have to not run it in ECO mode 
I just quickly googled a Honda 3000 inverter generator, it starts out as 3 ph, before rectification and inversion.
I donāt know the DC voltage but I assume it is at least equal to the peak AC voltage, which would be SQRT2 * 230V ish.
(But I donāt actually know anything about the inner workings).
Bear in mind that doesnāt have to be 3ph at 50Hz before rectification, though. A higher frequency will also result in smoother DC.
Exactly, which is why for something I may only need once a year, (if that), I am going to buy a cheap Asian ready-made DC generator.
I realize in ZA, ordering from China and actually receiving the item might be a tall order. That is why I am taking advantage of being in Ireland at the moment. I have resigned myself that I will probably have to arrange a shipping container when I retire.
So I am thinking about getting a cheap second-hand EV, to maybe go in that container.
Still undecided though.
(I think I have to own it for 6 months + and then I donāt pay silly taxes).
No, it must be at least 5V higher than the battery voltage for an MPPT input voltage and sufficient power.
That 12V output is neither.
You also cannot sell it immediately once you get to SA, I believe. It must be a vehicle you owned while overseas, and which you intend on driving in SA. You must keep it a certain number of years (I think?) otherwise they nail you with some pro-rata amount of what the tax would have been.
Thanks that would be the plan anyway.
Edit: I just looked up the red-tape nightmare that importing a vehicle could be.
I donāt want to furnish the taxman with any more info than he already has, so I think Iāll pass.