Changeover switch wiring help please

[Rory_d]

Hi guys 

 

Need a bit of help please, does anybody know how to wire this particular changeover switch please? I've attached a picture of the switch I've got. I can't find a wiring diagram for this particular one so any help is very much appreciated! Need to get this working desperately, 

 

Thankyou all in advance!

[David Mack]

Any reason why you can't wire it as the markings on the front say?

Bit surprised you need a 125A mains switch though!

[GUMPY]

It's written on it 🤔

[MtB]

54 minutes ago, Rory_d said:

Need to get this working desperately,

 

I'd suggest getting it working correctly, rather than desperately.

 

 

[Rory_d]

I don't know how it goes to he consumer unit. Can't understand why there's a bus bar, my theory of wiring it up doesn't match this layout at all. I can see the markings on it but need a diagram how it goes to mains hookup socket etc 

My understanding of it layed out as it is is that if the Inverter is on then I would assume the hookup socket will become live due to the bus bars.

[matty40s]

20 minutes ago, Rory_d said:

 

My understanding of it layed out as it is is that if the Inverter is on then I would assume the hookup socket will become live due to the bus bars.

I would assume you need to get someone competent to fit it.

[Rory_d]

I'm more than capable if i've got a diagram

[BEngo]

There is a huge gap between capable and competent.    If you were competent you would be able to draw the diagram you seek yourself  based on the clearly labelled item you have. 

 

Whether or not the things you describe happen up and/or  downstream of the c/o switch will entirely depend on the way your boat is wired. 

 

N

 

[GUMPY]

10 minutes ago, Rory_d said:

I'm more than capable if i've got a diagram

Obviously not, if you were you would understand it 🤭

[Rory_d]

Forget I even asked

[Tony Brooks]

50 minutes ago, Rory_d said:

I don't know how it goes to he consumer unit. Can't understand why there's a bus bar, my theory of wiring it up doesn't match this layout at all. I can see the markings on it but need a diagram how it goes to mains hookup socket etc 

My understanding of it layed out as it is is that if the Inverter is on then I would assume the hookup socket will become live due to the bus bars.

 

I agree that you probably need professional assistance because you think that you have bus bars, but I can't see any on that small image you posted. Just like inverters and solar controllers the screws you see are probably in something like a length of chock block connector under the plastic cove. That means they are all insulated from each other.

 

The image is too small to see if you have the line and neutral marked on each pair of terminals, but I think they are. The line and neutral cables that run to your consumer unit are at bottom right. You still have to ensure the integrity of the earthing and that is more complex, depending upon if the generator/inverter is neutral earth bonded or not. As we have said, you show every indication of needing professional assistance.

 

 

[jonathanA]

30 seconds with Google to find a diagram fus_sco125.pdf

 

Which seems to answer the concern I had about whether there was a chance of mains and generator being connected together simultaneously even briefly. 

 

If your trying to fit this in a standard CU with a bus bar from the main switch then you will need to remove that.

I would strongly suggest you heed the advice of consulting someone knowledgeable 

[David Mack]

It's a switch to allow domestic 230V ac circuitry to be supplied either from the mains or from a generator. It comprises two switches connected to a common red toggle, so that one input is connected and the other not. So the two inputs go into the marked terminals at the top, and the two outputs at the bottom are linked (by bus bars) so that there is one output connected either to the generator or to the mains, but never to both. That much should be pretty obvious from the markings on the front.

 

So in a boat situation you would presumably connect the output of your inverter to the generator terminals, and shore line to "mains". Then connect the "load" terminals to the input of your consumer unit.  If that wasn't obvious to the OP then he should get someone competent to fit it.

[Tracy D'arth]

I do hope it is break before make!     

Bang!

[Eeyore]

On 16/10/2022 at 19:18, Rory_d said:

Hi guys 

 

Need a bit of help please, does anybody know how to wire this particular changeover switch please? I've attached a picture of the switch I've got. I can't find a wiring diagram for this particular one so any help is very much appreciated! Need to get this working desperately, 

 

Thankyou all in advance!

Best to install this in a separate din style housing and connect the "load out" to the existing consumer unit input. Disconnect the existing mains in from the consumer unit and move it across to the new box.

Several reasons:

There is no apparent "centre off" position on the change over switch, so the existing master switch in the consumer unit will continue to fulfil that function.

The change over switch (even if it did have an off position) would require modifications to the existing consumer unit, such as cutting out part of the bus bars and installing flexible links as required. Not necessarily a straight forward job; and impossible to comment on without pictures of the existing consumer unit. 

Edited October 18, 2022 by Eeyore