G83 - 6kW limit

[Ivan]

I'm sure we've brought this up before, but I've failed to find it with the search facility.

I'm looking for the document which says the G83 limit was raised from 3.6kW/phase to 6kW.....but I can't remember who would have issued it - Electricity Association (they're called something else, these days) or Ofgem. Ted will probably know the answer!

[guydewdney]

in norther ireland:-
http://www.planningni.gov.uk/index/policy/policy_publications/planning_statements/pps18/pps18_annex1/pps18_annex1_active/pps18_annex1_activeconsents.htm

[Ted]

NI are the only place to do that as far as I am aware. The rest of the UK is still 16A/phase but with the DNO having the final say (they will usually allow more if the local network will support it).

[Ivan]

I'm sure I read that it had been updated a year or so ago across the whole of england/wales. I was also told that it would happen about 6months before by someone in the Electricity Association during a telephone conversation. Maybe it never happened after all? Wonder who you petition to get it done?

Been doing a bit of digging - here's what I've found so far:


http://www.ena-eng.org/ENA-Docs/eadocs.asp?WCI=SignOn&WCE=frmSignOn

(this is a note accompanying the G83 standard):

THIS WAS AMMENDED IN JUNE 08 - wonder what the ammendment covered?

This Engineering Recommendation provides guidance on the technical requirements for the connection of small-scale embedded generators (SSEGs) in parallel with public low-voltage distribution Networks. For the purposes of this Engineering Recommendation a SSEG is a source of electrical energy rated up to and including 16 Ampere per phase, single or multi-phase, 230/400 Volts ac. A two stage connection process is described. Stage 1 covers the connection of a single SSEG unit, either single or multi-phase within a single Customer’s installation. Stage 2 covers the connection of multiple SSEGs in a close geographic region, under a planned programme of work. This Engineering Recommendation only specifies the connection requirements applicable to those SSEG installations that are designed to normally operate in parallel with a public distribution Network. Those installations that operate in parallel with the DNO Network for short periods (i.e. less than 5 minutes) or as an islanded installation or section of Network are considered to be out of scope, on the basis that it is not possible to devise generic rules that will ensure safe operation under all operating conditions. NOTE 1:    For the connection of embedded generators with a rating greater than 16 A per phase, for Islanding and short term parallel conditions the reader is referred to Engineering Recommendation G59/1 and Engineering Technical Report 113. NOTE 2:    For the connection of small embedded generators with a rating greater than 16 A per phase the DNO may choose to use this Engineering Recommendation if it is considered to be more appropriate than G59/1. For example the connection of a 5kVA PV array or 10kVA Wind Turbine. The generic requirements for all types of SSEG unit are defined in the main text of this Engineering Recommendation, whilst the specific requirements for each different type / technology of SSEG are defined in the annexes. The generic requirements relate to the connection, installation and Network design requirements for connection of a SSEG to a public low-voltage distribution Network. Annex A contains further information on Network design. Annexes B - F describe a methodology for testing the particular types of SSEG in order to demonstrate compliance with the generic requirements of this Engineering Recommendation. By satisfying the test conditions in the relevant annex the SSEG can be considered an Approved SSEG for connection to a public low-voltage distribution Network. In the event that there is no annex for a particular type of SSEG, the matter should be discussed with the local DNO prior to connection, taking guidance from the existing annexes. The Appendices contain pro forma that have been designed to simplify and standardise type verification, Connection Application (for multiple installations) and Confirmation of Commissioning. This document does not remove any statutory rights of an individual or organisation; equally it does not

[Ivan]

I think it's the Electricity Network Association that makes the decision. Shame they don't answer their telephones 'You call cannot be processed at this time, Goodbye'! I'll try again later.

[ecogen]

Quote [THIS WAS AMMENDED IN JUNE 08 - wonder what the ammendment covered?]

G83/1 amended to G83/1-1. following a request to the Distribution code review panel from Ceres Power/Smart power solutions.
Main difference is Earthing in clause 6.4. This was done primarily for Fuel cells allowing connection of one pole of the DC side of the inverter to earth, as long as the insulation between AC and DC sides meets simple separation given in section 5.3.3 of EN60664-1 for basic insulation.
A few other minor general amendments / corrections. The only one of significance being the declaration table in Appendix 3 requiring loss of mains to be proved.
e.g; A momentary disconnect of supply to prove LOM protection operates.
The introduction of G83/1-1 was delayed until June 08 to allow [edit BS EN 50438] to come into force.

[Ivan]

Thanks, George. Nothing exciting there, then.

I spoke to our DNO today (western power). First phonecall was to a snotty lady who insisted that I wrote and applied for a grid-connection. I explained to her that I only have to notify the DNO if it's under 3.6 (or 6kW?) but she insisted. I asked why Western Power take a different approach from the other DNOs and got a load of nonsense in reply. Later I had a call from someone else at Western Power, much more knowledgeable and much more interested. He said that as far as he knows the 6kW limit hasn't come in, but they do have an official distinction between 3.6kW/phase and powers greater than 3.6 but less than 50kW - which are called grid-connect1 and grid-connect2. He said they normally accept grid-connect 2 under G83 as well, unless there's some major problem with fusing or cabling.

[baker]

 Hi new to this
 i see that it is ok to connect a 6 kw inverter g83 to grid
also been told can install a 10kw generator and 6kw inverter and dump the 4 left over
can any one tell me
turbine 10kw shenzhou /controler with rectifier/aurora  interface with rectifier and turbine dump load/ 4kw diversion dump load  switchand dump doad
a 6kw aurora inverter 
how is this done
 

[Ted]

Hello baker,  have you spoken to your DNO about this?

In many instances the 16A per phase limit is flexible. If your local network is up to it they may accept 10kW under G83 - they have discretion to do this if they are happy with it.

[Other-Power]

Hi Ivan,

Recently been talking to a sparky who has a West Wind 10kW wind turbine installed.

He is connected to the grid via two 3kW Windy Boys.

Being a sparky by trade he knew that the line could take it even though he is on the end of the line.

The DNO, Western Power had to put in some extra line capacitance which was going to be charged at £10k.

Of course a battle between my friend and Western Power started, ultimately because my friend is a sparky he ended up paying £1200.

Basically its up to the DNO but just because they said no dosnt mean thats really it.  You may need to hire an electrical engineer or a good sparky to prove to your DNO that the line can handle it.

Just my experiences with the 16A phase 'limit'

Jonathan

   

[jango]

Y.e.d.l dno in my area told 4kwp is ok under g83 and if over 4kw up to 6kw just ring then 1st to check.

[oliver90owner]

Just think about it a moment... Our single phase domestic supply is fused at close to 100A.  Does this not mean the 16A per phase is a political decision rather than a  practical maximum?  Or is there a problem using a local normal stepdown transformer as a step-up device?

regards, RAB

[guydewdney]

No Rab - its a balance question - and size of local transformer. My transformer is only 70KVA iirc

[Ivan]

I think the problem is that if everyone in your street has 16A per phase solar PV, then on a sunny day, they might have 100 x 16A fed into grid, whereas if you have your electric cooker on, your neighbour may be cooking on gas, or having sandwiches, or still watching the news - so you don't necessarily get the sum of all the loads at once.....a bit like the banks lending rather more money than they actually have.

[Ted]

The DNO have* a wider view of the local network and will take loading, voltage fluctuation and harmonic distortion into account.  It could be that the first one or two people to get an installation are accepted OK but that future installs on the same segment of the grid might run into problems.

* well, are supposed to. At a meeting last night someone was recounting how they couldn't even get Western Power to recognise that they already had a 3-phase supply in place!