elecronic play pen/man shed

[glinjik]

Hi I'm in the long build of my man cave / play pen, (hide out from the Mrs) so last year put the foundation down not very big 11x4m so far this year I've got the roof on and most of the external walls up  so now im thinking of power it works a little different here i have 3 lines of 240ish vac and a fourth line of neutral each line is capable of about 5kw so all you do here is split the lines in  house its normal one line downstairs one up and the third for garage etc what I'm wondering is should i put an independent ground in, I'm thinking oscilloscope

[Benta]

With "3 lines of 240" do you mean true 3-phase service?
And yes, a real protective earth is a very good idea. I don't know your soil conditions, but if they're OK, an earth spear could be an option.

[Ian.M]

It sounds like your mains supply is three phase.  If you are interested in old machine tools (Lathes, mills etc.), most above the entry level hobby ones have three phase motors so you'd do well to run all the supply phases to your workshop.

Apart from a clean ground always being preferable for test equipment, if this shed is an outbuilding it may be dangerous to extend the house ground (PE) conductor to it and a separate local TT grounding system plus a RCD (GFCI) protected electrical distribution sub-panel for the shed may be necessary.  If the mains supply has TN−C−S grounding its a red flag!    If its attached to the house, you may have no  choice other than to extend the house ground conductor to it.   
 
Consult a fully qualified local electrician to determine if you *NEED* a separate grounding system or even if its permissible to install one, as it depends on your local electrical code (regulations), the type of grounding of the electricity utility company's consumer supply distribution network, the quality of its maintenance and the risk of utility company supply and grounding conductors being vandalized e.g. by copper cable thieves.

[Bud]

Driving a few ground rods around the perimeter is simple. Just do it and bring the  grounding wire in while you can, you can decide later if to connect it.

[Benta]

It sounds like your mains supply is three phase.

That's a 100% open question, which is why I asked specifically. I have no idea about the Russian codes.
It could also be that as power requirements increased, new separate lines very brought in to the house, but still running on the same phase. Anything's possible.
True 3-phase would be nice, of course.

[Benta]

Driving a few ground rods around the perimeter is simple. Just do it and bring the  grounding wire in while you can, you can decide later if to connect it.

No one knows what the soil conditions are in the OP's area. In rural Norway, it would not be very simple (you know, granite and such stuff).

[glinjik]

Sorry for not replying yes its true 3 phase i can run three-phase motors (although i don't have any need) the ground is clay very deep with a very high water table, so drainage is always key here as for regulations that's a joke you do what you like they supply 4 lines 3live and one neutral that are connected to a 3 phase electric meter after that you do as you please there are rules but nobody enforces or checks work

[CatalinaWOW]

While there may be no chance of authorities checking your installation there are good reasons for doing it right.  Your personal safety is one.  Insurance companies also are unforgiving of imprudent decisions.

The hard part, if everything is lax as you say, may be finding good advice based on local equipment and conditions.