230 Generator poweringfuseboard & earthing

[electric will]

Why are they wired like that anyway? Is it for safety being used on building sites etc? It looks like a center tapped earth transformer but at 240 instead of 110

 

[Marvo]

Yeah, as E54 says, linking the N-E is bad/dangerous advice if the generator is internally configured as shown in the drawing above (V-O-V).

From the link you gave in post #13, can I assume you hired this generator? If you did then your best bet is to take it back and change it for one that's suitable for your application. Hopefully it's as simple as speaking to their tech staff and finding an alternative that's fit for purpose, it's in their interests as well to give you the right genny because the minute you link the N-E on that one they're going to be left with a pile of scrap as well as you'll be missing an eyebrow or two.

 

[Marvo]

They're wired that way because trailing leads or cables are particularly prone to damage, especially if the genny is mobile. If someone gets a shock from the trailing cable to earth then they'll only receive a 120v whack instead of a 240v one. Personally I'm not convinced this is their primary motivation, it's possibly also cheaper to manufacture this way...I'm not sure.

 

[aaelectric]

Marvo thanks for advice, i think your right about that as when i measured the voltage between ne utral & earth & live & earth it was 110v but with load connected it was no voltage from live to earth bit 240 from neutral to earth.
didnt know there was diffrent systems but u learn something every day.so this kind of generator is reLly only for power tools etc not for feeding a db. Do you know of one that can feed a db

 

[Knobhead]

Not on a V-0-V generator it won't!! lol!!!

Come on! At least it won’t be running light.

(No pleasing some people)

 

[electric will]

The more I think about the use of v-0-v generators the more concerned I'm becoming, what about people that use them to run caravans where is no hook up and I know some one that uses one to power a horse box while their away at shows, I'm also aware that there is a rcd in a small cu but then only single pole mcb's etc, surely this isn't safe at all??

 

[Marvo]

If you use them for a mobile caravan or horse box (why on earth do you need power there, there's already 746watts available without a genny ) that has no other incoming supply, they can be perfectly safe if the earthing is correctly installed. The bottom line is they're best just used for portable power with a trailing cable which is what they were designed for.

 

[Marvo]

Is this thread anything to do with you or is it a coincidence?

Thought it was worth highlighting cause there might be some useful info there for you as well.

There's some scary generator threads around this evening :-0

 

[electric will]

No marvo, neither thread is anything to do with me, I was just interested in the generator wiring diagram you posted, that's when I got thinking about the horse box-I fitted a inverter to horse box, well lorry once and they also used a generator because the inverter thrashed the batteries, don't get what you mean about the 746watts already available?

 

[Knobhead]

Will use this and look up horsepower

 

[electric will]

Will use this and look up horsepower

i clicked a little after I posted. Didn't know the exact figure but guessed it'd be to do with hp to watts.

 

[Marvo]

Sorry electric-will it was a joke but not a very funny one.

There's a link in the other thread I highlighted to the iet website and an article on portable generators but for some reason they don't mention V-O-V configuration, they only show generators as a single winding.