G83 - who says?

[Ivan]

Does anyone know who is entitled to certify a piece of equipment to G83 standard?

I assume that anyone can test and certify a product, as it's too specialist to be covered by a legally-required qualification or training.

For example, this company http://www.aelgroup.co.uk/ - did the G83 certification for Windsave. From what I can see, they have no specific qualifications or experience in G83-related matters, but are simply an electronics design/manufacture company.

[PhatBob]

Having a grub about on the Ofgem site it kind of suggests to me that the G83/1 certification is a subset of the EMC regs, so my first port of call would be your friendly neighbourhood EMC test lab.  They don't seem to advertise G83/1 testing on many of the sites but I'm guessing that's because there's probably not as much call for that particular test.

[Ted]

I know that SMA and Fronius do their own G83 certificates 'in house'.

If you have the right knowledge, competance and equipment I can't see that it would be a problem.

[ecogen]

G83/1/1 doc. 5.9 states that, Type testing and producing a test certificate is the responsibility of the SSEG manufacturer.  As the market develops for each particular type of SSEG then recognised test houses will undertake the task.
The SSEG is required to meet compliance with all relevant EU directives and the CE marking label applied.
The manufacturer upon request shall have available a verification test report detailing that the SSEG meets the requirements of the ER G83 doc.
The report must detail the type and model of the test unit, the test conditions and the recorded results. All of these details are for completing a typical test sheet shown in Appendix 4. As an example Ted posted a test sheet for an inverter here http://www.navitron.org.uk/forum/index.php/topic,4438.15.html
In the G83 annexes each type of SSEG has it's particular test requirements detailed, notably difference between solid state and rotating machines.
The manufacturer may choose to carry out these tests himself or employ the services of a test house.
The test sheet has a comments page at the end. It is here where you can explain how and where the test results were obtained if you were to use more than one test company or method in meeting compliance, together with limitations outside the products control.

It does appear that anyone one can take it upon themselves to meet the requirements of G83, however it is just not economically viable to do so especially in respect to an inverter.
The equipment test certificate is just one part of the SSEG installation, albeit a substantial majority using an inverter based system, however the whole system needs to meet the recommendation. Directly grid coupled rotating machines are dependant on their prime mover characteristic and this may not be exactly repeatable from one site to another, as can be the case for hydro. Therefore G59 may be considered. In practice and when over 16 A phase G83 Stage 2 process seems to blur into G59 as site witness testing of the protection seems mandatory by DNO's. Site relay tester DVS3 mk2 is £500 a week to hire.

As an example, the idea of using an induction motor and a "solar" relay to meet compliance with the recommendation.
1) No power factor control. Requirement between 0.95 lead, 0.95 lag. Unless otherwise agreed with DNO, in which case PF control equipment is essential.
2) Quality of supply (Partly dependant on prime mover). A motor is tested and CE certified to operate as a motor. Using one as an alternator will require type testing as an alternator. Compliance with EN61000-3-2 and EN61000-3-3. Part of EMC Directive.
3) Measurement of short circuit parameters.
4) Protection relay WILL require DNO witness testing on site as part of the commissioning. Does the relay meet requirements of IEC 60255-5 or equivalent standard?
These are the main stumbling blocks, there are many more but less of a problem.

OK how do we meet the requirements of G83 with this.
1) Design and build a circuit to measure power factor and switch in capacitors to maintain within spec.
Same standards and tests used in LV and EMC to be applied to all circuits.
2) Under automatic control, Excite the induction alternator by switching in capacitors, synchronise with the grid and close breaker. This method minimises inrush or "outrush" current, hence Flicker Pst. Using suitable test kit, test to EN 61000-3-2 and EN 61000-3-3. (Harmonics and Flicker)
3) Excite the induction alternator to rated voltage apply a full load. Using a suitable calibrated current recorder, apply a short to the alternator. Produce a current decay plot.
The plot will need to show the highest value of peak short circuit current. From this test, values needed to complete G83 Table 3 can be obtained. Refer to IEC 60909-1.
4) Arrange a commissioning date with DNO and hire a DVS3.
5) Best of luck.

If you are doing all this yourself does CE marking apply? As this "product" is not being placed on the market I would think not.
The reason for mentioning this is section 5.9.2 specifically states the SSEG unit shall comply with all relevant EU Directives and labeled with a CE mark.

Ted has written some excellent posts regarding G83 and grid connection in general which I can't fault and would advise others to follow.
I for one am a believer...... Hallelujah Brother (tic) *&%!*.

[scott]

if in doubt do not connect to the grid unless it has a certificate
saying its passed UK G83/1 or G59/1
any good inverter will also have
VDE126 AS4771 UL1741 etc

[ecogen]

if in doubt do not connect to the grid unless it has a certificate
saying its passed UK G83/1 or G59/1
any good inverter will also have
VDE126 AS4771 UL1741 etc

Thanks for the reply Scott, not everyone speaks to me, In the street most give a wide berth and others just step over me. I wonder why? (sniffs arm pit) PAGHH. What a relief, there was me thinking the problem was more serious!

Inverter Certification and type testing general arrangements. 
Note 2, Scope. For generators greater than 16A phase the DNO may choose to use G83, if it is considered more appropriate than G59. eg 10kVA wind turbine or 5KW PV.
Inline with this in Annex C. C1. Inverter manufacturers may type test their products that are over 16A phase.
Up to what limit under G83? The DNO's policy decision and issue of an internal reccomendation. 18KW single phase, 50KW three phase by some?
G59 type testing? First I have heard. Take for example G59 6.5 Test and commissioning. Connection to LV system. Protective equipment need not be witnessed by DNO. Tests must be carried out on site. Testing before installation is not acceptable.

I am of the opinion that although there may be no need for LV system protection witness testing, most installations are.

AS 4771 data transmission equipment operating in the 900 MHz, 2.4 GHz and 5.8 GHz bands and using spread spectrum modulation techniques?
The following standards may be more relevant to a "good inverter" if placed on the AUSTRALIAN market.
AS 4777.1 Grid connection of energy systems via inverters - Installation requirements. 
AS 4777.2 Grid connection of energy systems via inverters - Inverter requirements. 
AS 4777.3 Grid connection of energy systems via inverters - Grid protection requirements.

GOD I'm sad........and smelly!

[EccentricAnomaly]

if in doubt do not connect to the grid unless it has a certificate
saying its passed UK G83/1 or G59/1
any good inverter will also have
VDE126 AS4771 UL1741 etc

Isn't this a particularly useless answer in the context of the original question which is about how you get the certificate in the first place? 

Perhaps it would be better to answer the original question by, for example, imagining that the OP had a source for big steel boxes full of what appear to be perfectly good inverters at very reasonable prices but they only had, say, Martian certification at the moment.  Or something like that.

[sleepybubble]

if in doubt do not connect to the grid unless it has a certificate
saying its passed UK G83/1 or G59/1
any good inverter will also have
VDE126 AS4771 UL1741 etc

Isn't this a particularly useless answer in the context of the original question which is about how you get the certificate in the first place? 

Perhaps it would be better to answer the original question by, for example, imagining that the OP had a source for big steel boxes full of what appear to be perfectly good inverters at very reasonable prices but they only had, say, Martian certification at the moment.  Or something like that.

Scott seems to be mostly full of useless answers, most of which seem to end in 'contact me for full spec and price'. Anybody would think he was taking advantage of all the hobnobs still recovering from Glastonbury to litter the boards with a quick rash of spam advertising.

[SteveH]

if in doubt do not connect to the grid unless it has a certificate
saying its passed UK G83/1 or G59/1
any good inverter will also have
VDE126 AS4771 UL1741 etc

Isn't this a particularly useless answer in the context of the original question which is about how you get the certificate in the first place? 

Perhaps it would be better to answer the original question by, for example, imagining that the OP had a source for big steel boxes full of what appear to be perfectly good inverters at very reasonable prices but they only had, say, Martian certification at the moment.  Or something like that.

Scott seems to be mostly full of useless answers, most of which seem to end in 'contact me for full spec and price'. Anybody would think he was taking advantage of all the hobnobs still recovering from Glastonbury to litter the boards with a quick rash of spam advertising.

 Funny....  Thats just what popped into my head too....

[billi]

good to see a healthy Forum with self healing tendencies ...

Billi

[knighty]

http://www.g59-test.co.uk/page6.html

found that a couple of days ago and thought of this thread..... but then I couldn't find the thread

have been waiting for it to pop up since then :-)


can I ask what you want to connect ?  I'm desperat to connect a genny to the grid... and I'm sure there must be a better way than grid tie invertors... but I can't find it    (for a reasonable price.... not £25k etc...  fingers crossed for more like 5k)

[oliver90owner]

Knighty,

Wind genny, or diesel/biofuel/etc?

Windy Boy, the 5 kW, 4 blade self-build plans from the US use a system which might be certifiable.

Regards, RAB

[ecogen]

Knighty,
Thanks for posting the link, John is well known in the industry, he has been G59 testing for many years. You are unlikely to find anyone with anywhere near his knowledge and experience in this field. His service will cost you less than you can hire a T&R DVS3. The most relevant point is that he is known to DNO engineers confident that the job is done properly and an easy time had by all. Well worth the money in my opinion. However, I doubt he will take too kindly to clueless amateur self installers calling him up to pick his brains. Not aimed at you personally.

You can indeed ask what you need to connect. There are basically two rotating options, both G59 for sure, one definitely G83 and the other a possible if you are willing to jump through a few burning hoops and take a chance.
5K? Yes, possible up to 3 to 5KW for the electrical component side only. But to start with I need more info as to the size and type of prime mover as this is a critical part that directly effects the electrical output. "a genny to the grid" returns many possibilities, hemorrhoid cream being one.

[knighty]

hi, thanks for the reply/info/questions

I had planned to build a large generator using a 3 phase induction motor and something like one of those solar relays to connect to the grid... I was pretty confident in getting that working (belt driving the motor with an overrun clutch, actuator to take power on/off)

I'm pretty sure plenty of people do it that way  illegally, there's plenty of information about it on the net.... but no one who's actually doing it....  a bit more digging and it looks like the DNO will laugh at me if I want to have that certified ?

so far.... I have a huge old engine (1960, 11 litre straight six) which is perfect to run on beef tallow (which we produce loads of)

this is as far as I have got... I don't want to go any further until I know what I'm doing.... good information is very hard to find...

as for power output... we can happily use all the heat and power produced, so the only real limit is the grid connection.... initially i was thinking something like 30kw would be nice (across the 3 phases).... but maybe 18kw would be better to fit in under G83 (6kw per phase)?

it all really depends on cost...I have the money to spend, but business is pretty quiet right now... still making a profit but if I go spending 30k it will take a long time to build the bank balance back up again and it's more of a risk than I'd like to take...

[ecogen]

This project is G59 territory. I take it that this is a farm standby AMF installation and your DNO is Northern Electric. The first thing, contact NE and ask to speak to an engineer that deals with distributed generation. He will have access to all the infrastructure information appertaining to your site. Bear in mind that AMF systems come under G59 even though they are not in parallel with the mains. The DNO should have been notified before the installation was commissioned to have the opportunity to inspect and witness test  the change over equipment if desired. They probably will not be bothered after such a long time but if this has not been done don't open that can unless necessary.
If you are the only feed off the transformer all well and good. If the transformer has others connected this will limit the amount of export they will allow. Rough guide 25% of transformer KVA. Rural areas are more prone to the problems of voltage rise from distributed generation.
You must provide power factor control (easy to do), the range together with voltage will be stated by the DNO. Fault contribution will need to be assessed, your generators electrical performance characteristics may be required. Reinforcement of cable and switch gear may be required to accommodate fault infeed. You will need to provide a point of isolation under DNO control. This may take the form of a breaker to isolation standards. That's some of the connection requirements the rest is mainly process. The application will probably go through their design team for approval, it is important to get it right first time as requests for further information may attract extra charge.
Charging structure and rates are available upon request, if not on the web already. A written agreement for connection will be issued which will state responsibilities and conditions you will be legally obliged to comply with. Installation may then commence followed by inspection and witness testing

Converting your generator to parallel operation is easy to do.
1)The engine will need an electronic governor. These typically come in two parts, an actuator and a controller. Some modern units have the actuator and controller integrated into one. The latest engines have management systems which have the facility for remote speed control built in.
Fix the actuator as close to the injection pump as possible, this will keep the connecting link weight low to minimise it's inertia. The link connects to the throttle arm on the pump which currently will be fixed by an adjusting screw. You may have to obtain or fabricate a new arm if the existing one is too short or inaccessible. A load bank will be required to set up the governor to the characteristics of the engine. Adjustments are made to several parameters, the key one being PID gain which if correctly adjusted gives fast load response, minimal overshoot, no hunting and stable fine speed control for synchronising. The electronic governor enables the Generator controller to synchronise and load ramp.
2)Alternator. Years ago this was a problem because you needed to have some system to provide voltage droop. Generally this was provided by a droop enabled AVR and a droop CT fitted to the red phase. This was the minimum requirement needed to parallel alternators. If you were connecting to the mains then a power factor controller was also needed. A reactive load bank was required to set up the droop correctly or more importantly the same amount on all alternators so that they will proportionally VAR share.
Today all this is past and modern Generator controllers have all this built in. It is merely a matter of CT calibration and setting up correctly, it can all be done by a laptop on site.
You do however need a remote volt trim capable AVR. If your alternator is an old compound regulated type and not fitted with a remote volt trim diverter AVR, then it will be necessary to look for a generic type AVR that can be adapted to suit. Try here http://www.roperelectronics.co.uk/  I guarantee George will have a unit to suit.
3)Generator controller. Deep sea , Comap, Woodward, Deif, Megacon, DSF and  more to choose from. To start with I recommend looking at Comap http://www.ipu.co.uk/engine_info.asp?id=164903#pcm  Intelegen plus IG PCM, IG AVRi. This will get you on and off the mains and control power factor. Load control may require additional kit.
4)Suitable breaker or contactor for synchronising and the all important G59 relay.
5)Auto reclose circuit to reset G59 relay after 60 sec or to DNO requirement.
6)Install to BS7671 wiring regs. Earthing can be the supply earth if the generator does not island, subject to DNO agreement. Other wise you will have to supply your own earth to meet with approval. Neutral harmonics will need to be considered.

Provide documentation on plant operation and maintenance, wiring diagrams ect. Rat and mouse traps must be provided, note cats are not considered a suitable alternative.
Get liability insurance. 
This is only intended as a short outline guide of what you need to do. Best to engage the services of a professional company. There is a chap Generator Graham who posted recently who had a good rant about generators and mentioned G59. His web link was to a generator company. May be worth a try? No association.