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Joeboy wrote: ↑Tue Sep 07, 2021 4:39 pm

Stinsy wrote: ↑Tue Sep 07, 2021 4:33 pm

Joeboy wrote: ↑Tue Sep 07, 2021 4:29 pm Could spec system size, short spur it on its own breaker and use 16A IP rated plugs with rotary isolator? Suddenly, not very plug and play. Safer though..

What you describe as: "short spur on its own breaker" is really a: "dedicated radial" in which case you're good to go and can use a normal 13A plug/socket if you chose (although a 16/32A commando plug is more likely to be considered suitable). The danger really only comes from mixing loads/generators on the same circuit.

Fair enough on the wording! Someone made the point earlier on 13A pins being live but I don't think the system will power on solar side until it detects.mains power?

I must admit to.pricing a 4th set of 3 JA 325W panels this morning before heading to Dundee.

Any device intended to be grid tied would cut off power in the event that it didn't detect grid voltage.

Solar panels are so cheap these days you'd be silly not to add a few more. Particularly with winter coming. It isn't about how much "peak" power you can generate it is about how much you can produce in bright-overcast conditions (typically 25% of your kWp). You'd be best extending your 2nd system being careful to include Tigo optimisers if there is a chance of panels being lit/shaded at different times.

What voltage/current is your charge controller rated at?

Gonna start another thread so as not to be hijacking!

Thanks Stinsy.

"Any device intended to be grid tied would cut off power in the event that it didn't detect grid voltage."

Do ya feel lucky punk? would you trust it not to develop some weird fault and have live plug pins??

Not me, hard wired to an outlet and that admittedly small risk goes away, dedicated radial too, the overload risk goes away.

Desp

I just had a look at the UK latest regulations myself (BS7671, 18th Edition, 2018), Stinsy is correct in that you cannot use a plug and socket in an existing ring main. But looks like there is no restriction of a plug and socket if its a dedicated circuit from the supply side which has been mentioned before, by Stinsy in an earlier thread.
https://camelot-forum.co.uk/phpBB3/view ... =241#p1668

So, those Euro legal devices may be legal if you,

a) Plug them into a dedicated socket from the supply side.
Or
b) Cut the plug off and wire it directly into a double pole isolated fused spur from an existing ring main as long as the cable of the existing circuit can take the potential additional current. Or you down rate the over current protection device as appropriate.


BELOW FROM THE LATEST REGS
551.7.2 A generating set used as an additional source of supply in parallel with another source shall be installed:
– on the supply side of all the overcurrent protective devices for the final circuits of the installation, or
– 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

(iii) The line and neutral conductors of the final circuit and of the generating set shall not be connected to
Earth

(iv) Unless the device providing automatic disconnection of the final circuit in accordance with Regulation
411.3.2 disconnects the line and neutral conductors, it shall be verified that the combination of the
disconnection time of the protective device for the final circuit and the time taken for the output voltage
of the generating set to reduce to 50 V or less is not greater than the disconnection time required by
Regulation 411.3.2 for the final circuit.

Plug them into a dedicated socket from the supply side.

Are you seriously suggesting installing a 13A socket on the supply side of a Consumer Unit? BS7671 will be referring to hardwiring any generator connected at this position. No-one will have a socket in this position so the plug-and-play concept is a non-starter.

Pat wrote: ↑Tue Sep 07, 2021 10:19 pm

Plug them into a dedicated socket from the supply side.

Are you seriously suggesting installing a 13A socket on the supply side of a Consumer Unit? BS7671 will be referring to hardwiring any generator connected at this position. No-one will have a socket in this position so the plug-and-play concept is a non-starter.

I am not suggesting anyone do anything that is unsafe or illegal, but if you can find a reference in BS7671 to only hardwiring a generator on the supply side, please publish it here as I cannot find such a reference.

This thread is discussing that "plug in" low power legal grid tie products exist for a lot of European countries that are not legal here because of our regulations. The fact they are legal in several western European countries suggests you are unlikely to get a lethal shock by touching the exposed pins of the plug connected to the generator. This seems to be the sticking point to the UK regulations because they don't allow connection of a plug and socket in a non dedicated circuit, but paradoxically you can legally hard wire it in a non dedicated circuit via a fused spur, subject to having appropriate cable size and overcurrent devices.

The way the latest regulations are written, there is nothing I can see legally to stop a plug and socket connection on the supply side to a generator. But
in reality if you are adding a new circuit on the supply side for a generator its very unlikely you would want to connect it via a plug and socket as you would be limited to 13A and have a live plug if the generator did not have sufficient protections.

My personal belief is that the UK regulations are not keeping up with the reality of commercial products becoming widely available. Already we have seen DNOs introducing fast track G99 battery inverter connections subject to them being G100 compliant. When previously they needed to be full G99 applications but loads of devices are being sold online and fitted without any DNO notifications. I recall one recent story in the press of a particular DNO doing an audit in a local postcode area and finding only half the houses with PV had been previously notified to the DNO. Even an Octopus Energy blog about joining Octopus Outgoing was saying the process was slow because many installations had not been DNO notified even if the installation had an MCS certificate.

Full disclosure: I am not an electrician but I took the appropriate exams to be allowed by building control to wire my own house.

But in reality if you are adding a new circuit on the supply side for a generator its very unlikely you would want to connect it via a plug and socket as you would be limited to 13A and have a live plug if the generator did not have sufficient protections.

This would be my starting point. Using a plug/socket arrangement to connect two generators defies all common sense.

The way the latest regulations are written, there is nothing I can see legally to stop a plug and socket connection on the supply side to a generator.

If you provide the necessary protections in such a circuit, it becomes by definition a final circuit. And according to the regulations," a generating set shall not be connected to a final circuit by means of a plug and socket-outlet".

Pat wrote: ↑Wed Sep 08, 2021 10:51 am Full disclosure: I am not an electrician but I took the appropriate exams to be allowed by building control to wire my own house.

But in reality if you are adding a new circuit on the supply side for a generator its very unlikely you would want to connect it via a plug and socket as you would be limited to 13A and have a live plug if the generator did not have sufficient protections.

This would be my starting point. Using a plug/socket arrangement to connect two generators defies all common sense.

The way the latest regulations are written, there is nothing I can see legally to stop a plug and socket connection on the supply side to a generator.

If you provide the necessary protections in such a circuit, it becomes by definition a final circuit. And according to the regulations," a generating set shall not be connected to a final circuit by means of a plug and socket-outlet".

There are some additional regulations under section 712 specifically for PV Supply Systems.

712.411.3.2.1.1 On the AC side, the PV supply cable shall be connected to the supply side of the overcurrent protective device for automatic disconnection of circuits supplying current-using equipment.

The way I interpret this is that the PV inverter is a supply side item, therefore its not on the load side, therefore its not on a final circuit. And otherwise it would conflict with the first part of 551.7.2

551.7.2 A generating set used as an additional source of supply in parallel with another source shall be installed:
– on the supply side of all the overcurrent protective devices for the final circuits of the installation

But neither of those refers to adding a socket. Indeed my PV is connected upstream of the consumer unit (using a connection block) in parallel with the main supply.

Pat wrote: ↑Wed Sep 08, 2021 2:39 pm But neither of those refers to adding a socket. Indeed my PV is connected upstream of the consumer unit (using a connection block) in parallel with the main supply.

So's mine and its probably against MCS rules to use a plug and socket anyway.

But I suspect the electrical regs will in time change to allow low powered solar plug in devices if these things become mainstream, especially if they are legal in some western European countries. In a similar way that you used to need an earth rod for an EV charger but now chargers have become safer and the latest regs had to have an amendment so you don't need one in certain circumstances.

AMENDMENT 1 TO THE 18TH EDITION ON ELECTRIC VEHICLE CHARGER INSTALLATIONS
The regulations have changed around the earthing of electrical charging equipment at electric vehicle charging points, making the installation of EV charging equipment safer, easier and quicker and will reduce the cost of installations for both the consumer and the installer. This is due to advances in technology that weren’t available when BS 7671:2018 was first published.