I am a new PV householder - advice please. Unbalanced strings and wrong inverter

[provr6]

Not to rock the boat here at all but on the smaller string (6 Panels) did they reduce the startup voltage to 185v?

What's is the calculation to determine the min'm start up? I think it's something to do with one of the voltage specs on the panel x the No. of panels.

Is it detrimental to lower the start up voltage to the inverters min'm start up voltage in all situations?

 

[juniperz]

Better to keep the boat rocking now, that will save them the expense of putting up the scaffolding again in a couple of weeks.

When the wires chaff through in a couple of years / the roof leaks in the next big downpour, and they have gone out of business. Who is going to pay for it then?

These faults are actually just as, if not more important than the string / inverter combination.

They will not be able to sign off the commissioning certificate or issue a buidling regs certificate with the way it is.

What does the last sentence mean? I believe that the installer has to notify Building Control within a month or so, but if they think they have done a satisfactory job, what is to stop them just completing the two certificates you mention? Will Building Control come and check?

 

[MickF]

I reckon it would be possible to visit any install any body chooses and find soemthing that could have been done better with it.

However if someone says 'what do you see wrong with this?' it would be wrong not to give them your opinion, up to them then what they do about it. At least most of those items are fairly easily fixable.

And all credit to juniperz to act on the advice he's been given.

 

[MickF]

What does the last sentence mean? They are making declarations that everything this is right, so they shouldn't

I believe that the installer has to notify Building Control within a month or so, but if they think they have done a satisfactory job, what is to stop them just completing the two certificates you mention?
Nothing at all

Will Building Control come and check? They won't unless someone asks them to

​

 

[provr6]

What does the last sentence mean? I believe that the installer has to notify Building Control within a month or so, but if they think they have done a satisfactory job, what is to stop them just completing the two certificates you mention? Will Building Control come and check?

I think the previous post is a bit misleading (not mickf's but the one above your quote). They will be able to sign it off and commission it even if it's wrong (in their eyes its not wrong).

In terms of notifying building control within a month or so, I think you are referring to the Part P certificate. They have to issue their certficates within 28 days of comissioning (date on the mcs certificate) to Building control who will then issue a Part P certificate either directly to you or to your installer (some installers will ask for this to come to them and only release when paid in full).

This won't affect your fit registration. Strictly speaking Building control shoud be notified before the work started (not for Part P but to check the installation was being done to building regs - Don't worry too much though). Building control won't be interested in coming out and will issue the part P without looking at your install (unless you ask them to).

 

[Somecamel]

What's is the calculation to determine the min'm start up? I think it's something to do with one of the voltage specs on the panel x the No. of panels.

Is it detrimental to lower the start up voltage to the inverters min'm start up voltage in all situations?

Better still use this Power-One String Tool

 

[juniperz]

Better still use this Power-One String Tool

That's what I said at the top of page 7. And did ;-)

 

[Somecamel]

That's what I said at the top of page 7. And did ;-)

My bad, I need to learn to read

 

[juniperz]

And all credit to juniperz to act on the advice he's been given.

I have just hit 50 posts in a Solar sub-forum - I think I need to get out more!

 

[juniperz]

I think the previous post is a bit misleading (not mickf's but the one above your quote). They will be able to sign it off and commission it even if it's wrong (in their eyes its not wrong).

In terms of notifying building control within a month or so, I think you are referring to the Part P certificate. They have to issue their certficates within 28 days of comissioning (date on the mcs certificate) to Building control who will then issue a Part P certificate either directly to you or to your installer (some installers will ask for this to come to them and only release when paid in full).

This won't affect your fit registration. Strictly speaking Building control shoud be notified before the work started (not for Part P but to check the installation was being done to building regs - Don't worry too much though). Building control won't be interested in coming out and will issue the part P without looking at your install (unless you ask them to).

I just had a chat with one of the inspectors from Building Control. He didn't seem too concerned about the risk of water ingress from the brackets lifting the tiles, or brackets or untied cables. Certainly didn't think a visit was necessary, though also suggested that if the installer is in a "compentent persons scheme" they could self certify for structure and weather proofing, and he had no jurisdiction. No idea whether my installer is in such a scheme, though they are quite a large firm, so maybe they are.

I think I am on the verge of giving up the fight and getting on with my life...

 

[provr6]

I just had a chat with one of the inspectors from Building Control. He didn't seem too concerned about the risk of water ingress from the brackets lifting the tiles, or brackets or untied cables. Certainly didn't think a visit was necessary, though also suggested that if the installer is in a "compentent persons scheme" they could self certify for structure and weather proofing, and he had no jurisdiction. No idea whether my installer is in such a scheme, though they are quite a large firm, so maybe they are.

I think I am on the verge of giving up the fight and getting on with my life...

I know how you feel. TBH all you've got to do now that's important is get your fit application acknowledgement - then you can get forget about it and get on with your life and wait for the cheques to come in :25:

 

[Robinwood]

cbw, i think we should go for another company!!

 

[juniperz]

Internal Shots, Startup Voltage, todays peak output.
https://picasaweb.google.com/106757...719SolarInternal?authkey=Gv1sRgCKaD3c-WrL6eDw#
So should I fiddle with the startup voltage for string 1?? I.E reduce to 185V from the 199V it is set to.

 

[babba]

Internal Shots, Startup Voltage, todays peak output.
https://picasaweb.google.com/106757129624294668901/20120719SolarInternal#
So should I fiddle with the startup voltage for string 1?? I.e reduce to 185V.

Do you want an answer to this or should I stay in my can ?

 

[MickF]

I got a "sorry that page not found" on the link..

 

[juniperz]

I got a "sorry that page not found" on the link..

Whoops - I forgot to make the page public - should work now:
https://picasaweb.google.com/106757...719SolarInternal?authkey=Gv1sRgCKaD3c-WrL6eDw#

 

[juniperz]

Do you want an answer to this or should I stay in my can ?

Oh, go for it...

 

[SibertSolar]

I find it interesting that this whole business about "reducing the start-up voltage" is seen as a positive function. Out of curiosity, what are people's opinions on how this is achieved, the impact of doing it, and any consequences/trade-off by doing so? The old chestnut that always springs to my mind is "you get nowt for nowt in this world".....

I also find it interesting that some inverter manufacturers talk about "low voltage start-up" but they don't talk about "low power start-up".....

 

[Noshocks]

I was at a power one training day recently, they dont advise reducing the startup voltage as it has been set to achieve optimal output from the MPPT, not to say it wont still work, just not as efficiently. It must be said that any installer that new there stuff would have sorted this at design stage, reducing voltages to inputs is not going to achieve the kwh's estimated in my opinion.

 

[Earthstore]

My opinion here, for what it is worth, some are being harsh on the OP, and some of the information he has been given is not correct.
I am sure that some posters mean well, but do you not think that it would be fair to let the installers complete the install and get it registered, from what I have seen in the photos, although not perfect it is a reasonable install.
Do not start messing with the inverter, if it is not booting up (which it appears to be) then get the installer to "fiddle" with it.

I have posted before about building regs, the installer does not instruct them to visit, some installers can issue a certificate, and some can not, but you do not need building regs, just structural calculations, wind loading, and a part P certificate, and the lack of structural calculations may only cause a problem if you decide to sell the property.
Should you choose to get building regs, in my area the cost is £112, so it may be worth it for piece of mind, but it is not mandatory.