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#163320 - 05/06/07 09:03 AM generator set up and termination
britspark Offline

Registered: 05/28/05
Posts: 54
Loc: southampton united kingdom
just been out to look at a stand alone three phase generator,
now that in itself is the easy bit, stnading there looking at it, but this particular client wants it wired to a DB tehn to feeed a commercial vehical ramp and compressor.

luck would have it that the unit has a neautral!!

if it didnt he would have no chance,

my dilemma is;
the building has a single phase TT supply in place with various lighting and socket outlets connected to it, and a really nice buck boost single to three phase unit to run the hot room.

what codes (uk) would i have to use to allow me to connect the gen set to the building,
earething arrangements, breaker sizing, on load starting, etc etc.

it is a long time since i have had to tackle such a job, its usually a stand alone gen set with an interlock isolation unit and a autostart unit linked via the main DB.

and the main thing is (in the client part0 is the costing

what is was thinking (no drawing yet)
ground rod on the frame of the gen set, try to get a good Ze
35mm four core SWA to a 12 way 200amp DB with a D curve main MCB.
then feed all the equipment from that

Gen Set details
a 1956 V8 cummins diesel = 150 / 170 AMP three phase out.
its a big bugger!!

Any Ideas


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#163501 - 05/09/07 03:17 AM Re: generator set up and termination [Re: britspark]
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Gensets like that are a little out of my league too, but wouldn't you want to tie the earth back to the main TT earth rod for the installation? The neutral would have to be bonded at one point only as well, of course.

#163521 - 05/09/07 01:21 PM Re: generator set up and termination [Re: pauluk]

Registered: 12/08/05
Posts: 862
Loc: Titirangi, Akld, New Zealand
In New Zealand we usually connect generators up to the Neutral and Earth bars with a generator Neutral and generator Earth lead.
See 4th photo where the E and N leads are bolted to the E / N bar.

I have to say that these are temporary set ups in case of HT cable faults to 11 kV ditribution transformers.

See the photo's on this ECN thread i posted early last year.

Our NZ regulations are very close to th UK regulations as far as i'm aware

Regards, Raymond
The product of rotation, excitation and flux produces electricty.


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