G59 ENA application form help

[stubo300]

the only part of the G59 form i have left to answer is the section part 1a:

Peak asymmetrical short circuit at 10ms (ip) for a 3 short circuit fault at the connection point???

RMS value of the initial symmetrical short circuit (ik) for a 3 short circuit fault at the connection???/

RMS value of the symmetrical short circuit currant at 100ms (ik100) for 3 short circuit fault at the connection point????

any info would be great

many thanks

 

[BruceB]

The advice I have read from others is do not struggle to answer every question if you do not know the answer. If the DNO really are interested then they will ask you. Any answer you want ought to be available in the tech spec, the g83 certificate or the G59 certificate which are all downloadable. If the answer is not there it is probably not applicable.

Note that short circuit currents from PV are normally not an issue for the DNO by virtue of the design and/or laws of physics.

Regards
Bruce

 

[stubo300]

i phoned the DNO and they said that they can not process the application an less they have this information,

 

[BruceB]

You may be dealing with a jobsworth who does not understand the position. From the G59 certificate:

Fault level contribution
As SSEGs (small-scale embedded generators) for PV are inverter-connected, they are deemed to automatically comply with
regulations and no further tests are required.

The only thing I can suggest is a phonecall/email to sma to see if they can help.

 

[a1colly]

Has anyone else had any further dealings on this mater, I'm finalising my application for connection of 250KWP PV system and this has been requested before final approval. DNO have advised they aren't looking for accurate or precise figures just ball park and that they should be fairly low?

 

[SolarCity]

You shouldn't need to give details of this as long as you fill out section 1b is filled out correctly. And even then it should only apply to HV systems. Was this asked for after the initial application went in?

 

[a1colly]

Yes this has been requested after the application has been submitted. I've got a good relationship with the DNO hence why I only need rough calcs, but he does want the. Worked out rather than just details put in the box. The connection is to HV hence the need for them unfortunately.

 

[Worcester]

Then it depends upon how you are going to comply with G59 - are yiou using type approved inverters or a seperate G59 Relay?

If the former, then the information will be available in the Inverter's detailed G59 test results, if the latter then you'll need to get the details for the relay manufacturer.

Which DNO?

If it's WPD, then just gove your local area engineer a call.

 

[a1colly]

Hi yes it's via a separate relay due to the size of the install, the DNO is WPD, the area engineer is the one who has asked me to do the calcs, I'll check with the really manufacture to see if they can help out with the info.
Thanks

 

[tonyjones]

Hi a1colly I did a large scale solar design course with EcoSkies a few weeks ago, and one of the things they went through was how to fill in the G59 form. The answer they told us to use in the section 1a headed- Power station maximun fault current contribution is; "All 3 above are the same (1.5 x FLC) x no. of inverters, as electronic inverters incapable of providing short circuit current" or use the figure from the manufactures data sheet if they give it. The guy running the course was a hands on solar installer as well as a tutor and he said the DNO will accept that answer.
Hope that helps. Cheers Tony