PV Installation

[Darkone]

Hi people my first post on this forum.

I need advise with a proposed PV installation on my house.

I have a quote with a company to install the system for me which I am quite happy with, the only problem is one of the sub-contractors they use which happens to be the electrician. It is a personal thing and I do not want him on my property. Unfortunatley the PV company only employ this electrician.

In my past life I was/am an electrician, but this is not my line of business today. I am quite capable of installing the AC side of the installation and complying with the 17th regs. I would class myself as a "suitably qualified person". I still have various pieces of test equipment which have up to date calibration.

Reading through the miriad of posts on PV wiring I cannot see much of a problem on doing the work myself, even the PV company are happy with me doing my own work.

I know I going to be “slated” by the “must have qualifiaction paperwork” people, but please be gentle with me!

What would be the “pitfalls” and hurdles that I would have to overcome to stay on the right side of the law?

 

[Graeme Harrold]

If your not registered with a competant persons body, all you have to do is pop down the to your Council offices and notify them of the proposed work and hand over a heft cheque to cover the electrical and buildings works. Chances are you will not have the necessary equipment, qualifications or experiance to fit and complete the paperwork to qualify for your FIT payment...........

or

choose another installer.

or

bite the bullet and watch the sparky like a hawk.......

 

[dansk]

It gets messy (ish) under MCS, as you will be classed as either a "supplier" or "sub contractor" and this means putting agreements in place.

If i was you i would select another PV company if thats the case - im sure theres plenty more fish in the sea to choose from.

 

[Darkone]

If your not registered with a competant persons body, all you have to do is pop down the to your Council offices and notify them of the proposed work and hand over a heft cheque to cover the electrical and buildings works. Chances are you will not have the necessary equipment, qualifications or experiance to fit and complete the paperwork to qualify for your FIT payment...........

or

choose another installer.

or

bite the bullet and watch the sparky like a hawk.......

Hi Graeme, sadly the last two suggestions are not an option I am afraid.

As for filling in the paperwork I do have a friend who is qualified BS7671 and would keep me right on that side of it. My test equipment that I have are, earth loop tester, insulation (megger) clamp meters etc. What other specific equipment would I need to get the job done?

 

[Graeme Harrold]

Youll need a DC clamp meter, Irradiance meter and some way of taking the panel temp. As Dansk mentioned, option 1 is going to be messy, and it may result in you not getting the FIT payments.

 

[Darkone]

PV company say they are quite happy as long as I complete the paperwork (Part P, Bs7671 etc) they do the irradiance and panel testing. As far as I can make out it will be my signature on the inspection and testing report. Electrical testing hasnt changed much over the years it's just worded differently and the paperworks got more confusing, as has everything else.

 

[malcolmsanford]

Would there be RCD protection for this installation ?

 

[Darkone]

Would there be RCD protection for this installation ?

Hi Malc:smiley2: Why this question?

 

[Graeme Harrold]

I think because you made no mention of an RCD tester in your list of retained kit...............

 

[Darkone]

I think because you made no mention of an RCD tester in your list of retained kit...............

Ahh rumbled :biggrin5:

My mate has one though which I can use, and a clamp meter, and spare loop tester etc.

I believe that it may not be neccessary to fit an RCD as the inverter has a transformer, although I think there may may be a cause to fit one because of REG 551.7.2, yes/no

I noticed quite a discusion on this forum with regards some of the Inverter manufacturers specifing 100mA RCD when the UK has 63mA

Malc boy seems to be on the ball with this lot, I was pretty interested with his views on Earthing the array frames and PME.
I recently had a discusion on PME with a a supply company forman in charge of updating overhead supply lines to properties. He commented on how many pole earths in the main lines were missing and that he thought that the PME system may not be as good as it should be, food for thought

I have had discusion with my proposed PV installer and they say they are now only fitting Class II insulated systems and the inverter they use has a transformer, and that the array frame should be left floating, As you all know The DTI's Array Frame Decision Tree says "leave floating" I wonder how good the Class II panels are?

I am scratching the old grey cells on this and trying to get myself upto speed on the whole issue of the new regs. Be gentle with me

 

[Eco Deal]

sounds like it is alot of hassle just because you dont want a certain person in your home which is understandable but it would be easier to get a diffrent MCS company in to do the work , save all the trouble

 

[Worcester]

@Darkone you really have two choices here:

1) Instruct the supplier you currently favour that if they want the work they must find another electrician.
or
2) Find another installer. try Find a solar installer - UK Solar Installers | Solar PV | Solar Thermal | Quotes | Local Installers | Solar Power | Feed in tariff | RHI |

That's it, everything else will cause you significant problems, and cost you more in the long term.

 

[malcolmsanford]

As you saw I'm personally not impressed with the DTI introducing German standards into our industry and manufacturers not adapting their instructions for the UK market, but that is another discussion.

As you know 551.7.2 does recommend the use of an RCD for generating sets in parallel which a PV array is, but like all our regs it seems to once again be open to interpretation. Some think as you are reversing the flow into the installation the top of the protection device becomes the supply side and the bottom of the device the load, IMO that is not correct a protection device is not designed like that and the supply should enter the bottom. So if I were doing an install and utilised an existing MCB in a CU I would class that as load side of all protection devices and fit an RCD as per the reg which is a 30mA type, that though is just my opinion and my interpretation.

As you are fitting an inverter that has simple separation there is no need to fit an RCD to protect the circuit, if as the DTI suggests that you fit a small single enclosure which will be separate from the main CU. Of course if the manufacture insists on RCD protection you need to fit it and that would be your 100mA one. But if you bury the cable within a wall or partition less than 50mm and it does not have protection as to regs 522.6.6 then you need the additional protection of a 30mA one.

As for earthing you don't require it as you say for an inverter that as simple separation via a transformer. Yes the panels are class II and the DC cable is double insulated so therefore the array frame would not be classed as an exposed conductive part and therefore not earthed.

 

[Darkone]

sounds like it is alot of hassle just because you dont want a certain person in your home which is understandable but it would be easier to get a diffrent MCS company in to do the work , save all the trouble

Ohhhh I do like a chalenge, It's enjoyable getting up to speed with the whole issue of PV as it is a long time since I put together and designed a project.

@Darkone you really have two choices here:

1) Instruct the supplier you currently favour that if they want the work they must find another electrician.
or
2) Find another installer. try Find a solar installer - UK Solar Installers | Solar PV | Solar Thermal | Quotes | Local Installers | Solar Power | Feed in tariff | RHI |

That's it, everything else will cause you significant problems, and cost you more in the long term.

Unfortunatley the supplier is one of my customers and he has given me a "cracking" price on the PV system, so going to another installer will cost a lot more.

If I don't go down the install the AC side myself I may push them to find another electrician, I have a lot of fellow sparky's as friends but none of them are doing PV although they all do electrical inspection and certificating.

Can someone point out the difference between a standard qualified sparky and one who installs PV?
Is it just the MCS cert?

 

[Worcester]

@Darkone see the comments here: http://www.electriciansforums.net/p...mcs-solar-pv-company-who-not-electrician.html

 

[grandfortune]

just employ another electrician, all he has to be is part p registered, that it, simples, if your PV company want the work they'll get another spark anyway just for this job. if your stuck i'll do it for £180 + 36p per mile, that's what another company pays me.

 

[SolarCity]

once in the loft knock a wooden board up around 800x600, mount a rotary isolator and put your cable to that, once thats done, everything is prepared for the PV installers to come in and mount the inverter onto the board along with DC isolator

Of course, the board needs to be fire retardent.

 

[Graeme Harrold]

Of course, the board needs to be fire retardent.

Or covered with flame board...............