plug in solar isn't legal here in the UK as the legislation and government are a bit slow.
I have covered this in some detail in the legal part of the forum as well as updated the wiring requirements information on https://www.renewsolar.co.uk/company-information/blog/delving-into-bs-7671-section-712-and-solar-panel-systems/
As you know, you can have a electrician install a dedicated circuit, this would be installed on the supply side. however if you wanted to vacate this cost, then the other alternative is to follow the guidance:
– on the load side of all the overcurrent protective devices for a final circuit of the installation, but in this case all the following additional requirements shall be fulfilled:
(i) The conductors of the final circuit shall meet the following requirement:
Iz ≥ In + Ig
Where:
Iz is the current-carrying capacity of the final circuit conductors
In is the rated current of the protective device of the final circuit
Ig is the rated output current of the generating set
(ii) A generating set shall not be connected to a final circuit by means of a plug and socket-outlet
The first step is to remove the plug.
We can wire a different plug, like a commando. This removes the "live pin" risk.
Lets look at the math shown in the big book..
Iz, this is usually 2.5mm T&E, they can be radial or rings and you should know the difference. the conductor is the wire.
Iz = 24 amps
In = this is the breaker, or fuse. Typically 20 amp. but on a ring main it will be 32amp.
Ig varies and you will find this on the generator (inverter) as its current output AC.
In theory, (not in real life) the ring main is doubled up, therefore the theory is 50 amps current capacity (Iz) but in reality it is not.
We will look at the radial. which gives us 4 amps at (Ig.) this gives us inverter power of 920W.
Therefore we need to add protection to the circuit. a 4amp MCB will provide some protection, we also want RCCB and SPD and the cost runs up.
You also need dual pole. and good luck finding a 4 amp RCBO. they don't make them. the lowest is 6 amp.
On a ring 6 amp would run you a 1360w inverter.
So the plug we removed, should be correctly wired to an enclosure unit, thought the protection and then exit. it would go to a commando or AC Isolator which is hard wired in.
smaller inverters should be protected at a lower power. You may wish to return to the distribution with a 4 amp MCB.
Remember inverters have some protection built in, but if that fails, the "house protection" ( what I have said above) provides that fault correction as to stop wiring fires or inverter fire. I will repeat myself here, but for the costs you should be able to have a supply side installation carried out as the hardware is around £100-160..
conclusion....
Plug in solar is NOT plug in solar.
People are asking how to wire these into there homes, we do not offer advice on theses systems or how you could wire these into your home safety and legally. Our installations services and project management services offer installations and our consulting service offers advise from the paid services.
Replacement of a socket to a genport for connection with the protection circuit could be an option as well as a new circuit going to an isolator.
What is the difference? there is a BIG difference and installing a gen port is not just a matter of just changing the socket to the gen port. What wiring is there? whats the line loads? will I exceed the protection limits, will i void my protection for my entire home. These are just a few things that have to be considered.
less complicated is to call your local electrician and ask for a isolator to be installed on a new circuit, this can be on the Henley block where the power comes into the house, or at the consumer unit. you will want to have protection installed that works both ways to protect the home and items that are attached. then you can attach your inverter.
What to protect or install, is a matter of what your installing or going to install.
for example a 800w inverter will supply around 3.4 amps. a 1200w inverter 5.2 amps and a 3kw inverter 13 amps.
if you have multi installations on the cable ( bus line) then 3 800w and a 1200w will need to carry 15.4amps
Therefore the cable ( bus line) would need to support the load here and the wire between the bus and the grid attachment would also need to carry this load.
When going to replace a socket, you would be limited to the cable and circuit design and the load ( solar) you want to put into this circuit.
Do you present a fire risk or a protection risk? also this will limit the expansion of your solar as you would not be able to add more inverters.
AS you can see there are Pros and cons to the way you install.