Isolator Switch wiring

[DSTransmissions]

Hi all

I'm trying to connect a diesel generator to a fusebox that then feeds into what was previously the mains meter, now cut off from the mains, in order to power the lights and plug sockets in a builder's hut on my yard.

I have a 3 pole isolator switch (this one - https://www.motorstarters.co.uk/en/25a-3-pole-sw-neutral-boxed-isolator - the smaller square one at the front, I think the accompanying data sheet covers both models pictured?), but I don't know which terminal(s) on the switch to connect the live/neutral/earth wires to for either the generator or the fusebox.

Can anyone help me out with a simple diagram or straightforward explanation?
Something like

T1- Live (generator)
T2 - Neutral (generator)
etc.

would be great

Also, does the switch need to be individually earthed or will earthing the fusebox be sufficient?

Some additional clarification -

* - The mains power is no longer connected and hasn't been for a long time. It wont be reconnected while this setup is in place. The wiring from the fusebox to the building itself was done by a qualified electrician, as was the wiring inside the building.
* - I'm using outdoor rated sockets/plugs/switches, waterproof where necessary
* - Building regs are not really an issue - the setup is behind two locked gates that only I have a key to and the building itself is not classed as a permanent structure, being essentially a jumped-up Portakabin.

I'm imagining the brand of generator/fusebox really doesn't make a huge difference in how this would be wired, which is a good job because I don't have either of those pieces of information to hand.

Any help greatly appreciated. Ta!

 

[Simon35]

How will the installation be connected to earth? Are there existing spikes in the ground? You need to make sure they are present and tested before you start lashing the genny in. I'm going to assume you don't have the appropriate test equipment so get an electrician, and for not much more money he or she will connect the genny.

 

[DSTransmissions]

Thanks Simon. The fusebox is already earthed to a metal fence post. Does the isolater switch need to be earthed as well?

Everything else is already in place, it's just this one last bit of wiring I need to do to finish it off and I'd rather do it myself rather than calling anyone out. It's all good learning y'know?

 

[securespark]

Not if you kill yourself in the process!

You don't switch earthing conductors by the way...

 

[JohnD]

The fusebox is already earthed to a metal fence post.

Haha!

I understand now!

It's a joke thread!

 

[Simon35]

Thanks Simon. The fusebox is already earthed to a metal fence post. Does the isolater switch need to be earthed as well?

Everything else is already in place, it's just this one last bit of wiring I need to do to finish it off and I'd rather do it myself rather than calling anyone out. It's all good learning y'know?

What kva and voltage is the genny?

Earthing isn't straightforward with generators.

The bit of wiring isn't all you need to do to finish it off. Testing is what you will need to do to finish it off. You can't do that if you dont know how an isolator should be connected. Please take this in the spirit it's meant and get an electrician.

 

[DSTransmissions]

**** it, if none of yous are going to tell me how to wire it I'll just guess then.

 

[endecotp]

If the system is not properly earthed, you may get shocks from the cases of any metal items that you plug in even if nothing is faulty. To make it worse, it only takes one device to be faulty and all of the others become live. (With an effective earth, something would trip before that happened.) There is quite a serious risk here; you might die.

If the metal fence post was being used as an earth electrode when you had a mains supply then it may still be usable now, but it would be best to check; a special meter is needed for this. More likely it's not really an earth electrode at all, but just something that had to be bonded to earth for reasons too obscure to discuss here. You must also consider if/how any earth electrode must be connected to neutral. Maybe your generator already does this; maybe there is a link you have to change etc.

I think that the switch you linked to is probably intended for 3-phase supplies; I take it you don't have a 3-phase generator?

 

[ban-all-sheds]

The fusebox is already earthed to a metal fence post.

WT*?

Has that been properly tested?

Building regs are not really an issue - the setup is behind two locked gates that only I have a key to and the building itself is not classed as a permanent structure, being essentially a jumped-up Portakabin.

They do apply re Part P & notifiability of electrical work.

There are no exemptions based on what the structure is - even if it is exempt from every other Building Regulation it is not exempt from either Part P or Regulation 12.

And locked gates are an irrelevance anyway.

**** it, if none of yous are going to tell me how to wire it I'll just guess then.

But you have been told how to wire it.

get an electrician

get an electrician

The problem is that you are one of those walkoffs who has decided before coming here what advice you should get, and who is refusing to even recognise advice which does not fit with what you have already decided to do.

Good luck - I hope that if anybody dies because of your wilful negligence it is only you, and not some innocent 3rd party.

 

[bernardgreen]

**** it, if none of yous are going to tell me how to wire it I'll just guess then.

in which case you may require advice from this site

https://www.resus.org.uk/cpr/

 

[davelx]

WT*?


There are no exemptions based on what the structure is - even if it is exempt from every other Building Regulation it is not exempt from either Part P or Regulation 12.

.

Surely Part P does not apply if this yard is not a dwelling and is not fed from or associated with a dwelling?

 

[bernardgreen]

Whether Part P applies or not there is a Duty of Care that requires the site to be safe to work in. And that means electrical installations must be safe and that requires that the person installing them has to be competent and have the necessary knowledge to design and install the system.

 

[davelx]

Whether Part P applies or not there is a Duty of Care that requires the site to be safe to work in. And that means electrical installations must be safe and that requires that the person installing them has to be competent and have the necessary knowledge to design and install the system.

Indeed - has anyone said otherwise?

 

[bernardgreen]

Indeed - has anyone said otherwise?

That was intended to try and convince the OP to get a competent person to connect the generator and not try to excuse any incompetence by claiming Part P wasn't applicable to a site.

 

[ban-all-sheds]

Surely Part P does not apply if this yard is not a dwelling and is not fed from or associated with a dwelling?

You are quite right.

Leave it with me and I'll see if I can invent an excuse.