Solar Panel Guide Discussion

zeupater

John_Pierpoint wrote: »

http://www.bbc.co.uk/programmes/p017y1zq

http://www.bbc.co.uk/programmes/b01s09z3

Hi John

You would have thought that both the BBC and the guest academics would be aware that fuses (and later breakers) had been developed so as to create a sacrificial, easily repairable 'weak points' in the circuit between the early Victorian era and now and would therefore have taken a fraction of time to have mentioned it instead of portraying Victorian 'overload', 'electrocution', 'fires' & general communications Armageddon to the general public as if it would still be the case .... sounds more like a daily newspaper's approach than what would normally be expected of the BBC ...

Z

Martyn1981

Martyn1981 wrote: »

Will keep an eye on voltage today, but it's definitely fluctuating more than 2 years ago, when it was a more 'solid' 242V.

Just a quick update. Voltage seems to be staying around 239-245 since Saturday. But I may have made an error!

I checked the voltage on Sunday at 2pm and 5pm, both times around bottom 240V. But it's since occurred to me that both times might have caught slightly higher demand, whereas between 2pm and 5pm might have been lower demand, and higher voltage (have I got that the right way round?).

So maybe, nothing to really go on yet. I'm also starting to think that the combination of freak spikes, 5.1kW and high voltage 253V+ is probably more than a co-incidence.

Anyone know if high export is 'instantly' diluted by the local grid, or might last long enough to create its own problem.

Lastly, generation on that day was fine from the WNW system, about what I expected. And looking at the playback feature on the SolarEdge monitoring site, I couldn't see any zero periods, so the 'shutdowns' must have been short enough to be absorbed into the larger time period.

All quite interesting - as long as it doesn't keep happening or become a serious issue. Or as my mother used to say, 'it's all fun and games, till somebody loses an eye!'

Mart.

zeupater

Martyn1981 wrote: »

Just a quick update. Voltage seems to be staying around 239-245 since Saturday. But I may have made an error!

I checked the voltage on Sunday at 2pm and 5pm, both times around bottom 240V. But it's since occurred to me that both times might have caught slightly higher demand, whereas between 2pm and 5pm might have been lower demand, and higher voltage (have I got that the right way round?).

So maybe, nothing to really go on yet. I'm also starting to think that the combination of freak spikes, 5.1kW and high voltage 253V+ is probably more than a co-incidence.

Anyone know if high export is 'instantly' diluted by the local grid, or might last long enough to create its own problem.

Lastly, generation on that day was fine from the WNW system, about what I expected. And looking at the playback feature on the SolarEdge monitoring site, I couldn't see any zero periods, so the 'shutdowns' must have been short enough to be absorbed into the larger time period.

All quite interesting - as long as it doesn't keep happening or become a serious issue. Or as my mother used to say, 'it's all fun and games, till somebody loses an eye!'

Mart.

Hi

Our supply is hovering around the 246.7 (+/-0.5) mark at the moment, it was around 243V earlier ... when our inverter quickly swings from ~1kW to ~4kW due to cloud edge effect it doesn't make any difference to the supply voltage that I can distinguish from the normal fluctuations ...

HTH
Z

spgsc531

Cardew wrote: »

There really isn't much point in attempting to use logic with those two.

'ad hominem' sums it up.

The script writes itself cardew:

spgsc531 wrote: »

Ignoring everything else, this really did make me chuckle. Well done cardew.

John_Pierpoint

zeupater wrote: »

Hi John

You would have thought that both the BBC and the guest academics would be aware that fuses (and later breakers) had been developed so as to create a sacrificial, easily repairable 'weak points' in the circuit between the early Victorian era and now and would therefore have taken a fraction of time to have mentioned it instead of portraying Victorian 'overload', 'electrocution', 'fires' & general communications Armageddon to the general public as if it would still be the case .... sounds more like a daily newspaper's approach than what would normally be expected of the BBC ...

Z

I think in fairness to the BBC in the second link to the whole programme, they do explain the difference between Quebec, where lots of the system was knocked out, and the UK where there are multiple connections to most locations. The electricity network man explained that they would have 20 minutes in which to open up all the interconnectors before the induced current arrived, in the hope that the massive additional surge could be dissipated without burning out too much of the kit.

Presumably a PV panel owner would be best advised to switch off both the circular bi pole switches next to the inverter, and then pray during the remainder of the 20 minutes, that the voltage would not jump the gaps to get at the isolated inverter?

By coincidence the breakfast series "Don't get done get Dom" featured a woman on a farm, who had her system burnt out "by a power surge" and then received a £2,000 bill. She thought the two events were in some way related.

Needless to say the programme was short on technical detail and simply turned out a joust between the BBC and Scottish & Southern Energy. How ever I did notice that she was on a three phase supply, not exactly the typical consumer.

orrery

And these things are often not easily protected against - you can't assume that a fuse will always protect you. Fuses will only protect against over-current (and then after a delay) and not over-voltage (unless you get some pretty meaty suppression in there too).

I remember hearing of a case where a woman ran a business in a remote set of serviced offices out in a village somewhere. Her fax machine would blow up regularly. BT spent some time investigating and concluded that - somewhere along its length the fax line ran alongside some other cables for a significant distance and that over-voltages were being induced on the line. Not sure if it was ever resolved, but I'd guess that the problem would be trivial compared to that induced by a solar storm..

Hadrian

I thought this forum was about Solar Panels, what the heck is all the above blather about??

KevinG

Hadrian wrote: »

I thought this forum was about Solar Panels, what the heck is all the above blather about??

Strangely not, the forum is "Green & Ethical MoneySaving" although sometimes you do wonder.

Martyn1981

KevinG wrote: »

Strangely not, the forum is "Green & Ethical MoneySaving" although sometimes you do wonder.

Hiya Kevin, you're not wrong there, and I'm one of the guilty ones!

Still, in my defence, this is a green and ethical forum, on a web-site in a country where over 80% of people support renewables.

And the favourite renewable with 85% support and only 4% opposition (though it's hard to believe reading these threads sometimes!) is ......... drum-roll ............ solar. :T

Mart.

spgsc531

Hadrian wrote: »

I thought this forum was about Solar Panels, what the heck is all the above blather about??

The blather was because zeupater (& cardew) wouldn't admit to being wrong.

To explain the lengthy responses it's probably fair to point out why.

cardew has a very vocal anti-FiT (Feed in Tariff) stance. Fair enough.

He also has a regular tendency to state 'facts' that are clearly wrong to further his 'cause'.

He will never admit he is wrong, and also has a tendency to 'slink off' when proven wrong then resurfacing a while later.

For some bizarre reason zeupater decided to attack me because he decided I was personally attacking cardew. In defending cardew he felt he had to defend the wrong figure, which ended up with his protracted obfuscating posts. It is now clear that zeupater is also not able to just simply say the figure is wrong.

The figure is important because unless checked cardew has a habit of posting 'facts' that are wrong, that could mislead people. For this reason alone, I have tried to point out when this has happened. Apologies to those who don't like it, I feel it is very important.

Spgsc