Something does not add up..

[danesol]

Today my owl has measured 12.1 kWh generated from CT clamps, PVoutput logged from the inverter is showing 12.5 kWh that's a 1% difference in my calculations are correct

Helmshore sun trap ! 4.000kW

I'm not really questioning the smartness of my energy usage, im just not really seeing the difference in my import meter that i would expect based on my generation, maybe it is just me meter configured wrong..

Does your OWL work out what your actual export values are ??

As looking at your PVO account - they either arent posted or you have PVO settings set incorrectly ??

As said above - you wont see a great reduction in your electrical bills Jan-Feb and Nov-Dec, especially if your export percentage is high as well.

 

[danesol]

Hope you dont mind, but another observation just looking at your LIVE data - your voltage seems to go a little high - you may have to keep an eye on that when the production really kicks in, as your Inverter may start to shutdown if it gets too high.... assuming that (grid) voltage figure is accurate btw


ps> where is that Temperature value coming from too ??

hth

 

[Uklad]

The data on the PVO is direct from the inverter the TEMP is the inverter temp i think, i can not find a way to link the owl data into PVO.. so the export is just the same as generated.

on a side note about the grid voltage i have noticed its a bit high but for a few days in feb is dropped but came back up

Helmshore sun trap ! 4.000kW | Live Output

Is there anything that can be done about the high voltage

 

[danesol]

The data on the PVO is direct from the inverter the TEMP is the inverter temp i think, i can not find a way to link the owl data into PVO.. so the export is just the same as generated.

on a side note about the grid voltage i have noticed its a bit high but for a few days in feb is dropped but came back up

Helmshore sun trap ! 4.000kW | Live Output

Is there anything that can be done about the high voltage

Well as long as it isn't ambient temperature around the Inverter you are OK

With regards Grid Voltage, just keep an eye on it as it may cause an issue when fully generating, are there any other Solar PV arrays in your surrounding area that you know of on the same sub-station ??

If you do have issues - May onwards, you or your installer could try speaking with your DNO about lowering the grid a wee bit, as I personally found my DNO very helpful when I reported that voltage was too low in our road on every phase ( 216Vac ), however I suppose it did cost them a fortune in my repair bills so may have been over obliging in my case switching the network within 3hrs of the callout ( after checking other random houses in the road on each phase ) but are not obliged to do anything unless its outside std +/- tolerances.

 

[Uklad]

I know of 1 other system that is on the same sub station looks in the region of a 2kWh, i have long had issue with halogens popping way to soon and LED transformers not lasting long..

 

[danesol]

I know of 1 other system that is on the same sub station looks in the region of a 2kWh, i have long had issue with halogens popping way to soon and LED transformers not lasting long..

Well if you do have a voltage issue at some point, check with your neighbours as if they are also experiencing high wear & tear - as you may find that approaching a DNO in bulk, is a lot lot easier with a more favourable result, especially if they have to fork out for replacements like they did with me.

 

[danesol]

Is there anything that can be done about the high voltage

Other than DNO involvement, if its constant high voltage - you could consider one of these as they may suit your situation ;

http://www.electriciansforums.net/p...e-optimisers-pv-array-high-grid-voltages.html

 

[Gavin A]

The other thing to consider is that occasionally some installers have incorrectly connected the PV to the WRONG side of the consumers meter, so you're not getting the benefit of anything you generate (except the FiT).

How is your's wired in - a photo would help us and save a dozen posts asking for more detail.

yeah, rings a bell that one.....:redface:

looking at the figures again, it's not that unlikely that they're actually right though, given the rubbish march we've just had, could be explained by more lights being in use, or something being used more in the house - it's not that different.

Definitely worth keeping a proper eye on it though - we've had to replace a landis meter for someone recently that was reading much higher than it should, we put it on test in series with another meter and it's now reading around 50% higher than the other meter, having worked fine for 3 years.

 

[Worcester]

Definitely worth keeping a proper eye on it though - we've had to replace a landis meter for someone recently that was reading much higher than it should, we put it on test in series with another meter and it's now reading around 50% higher than the other meter, having worked fine for 3 years.

Hope it was his generation meter

 

[Uklad]

Hope it was his generation meter

I was wondering the same

 

[Earthstore]

The other thing to consider is that occasionally some installers have incorrectly connected the PV to the WRONG side of the consumers meter, so you're not getting the benefit of anything you generate (except the FiT).

How is your's wired in - a photo would help us and save a dozen posts asking for more detail.

I considered this too, but if his import meter is showing RED then it must be connected in after said meter.

 

[moggy1968]

contrary to the above your voltage will reduce from may onwards as the panels become hotter. max voltage produced is likely to be about now when the panels are cold.
current is more affected by the amount of light than voltage. Voltage is affected more by temperature

 

[danesol]

contrary to the above your voltage will reduce from may onwards as the panels become hotter. max voltage produced is likely to be about now when the panels are cold.
current is more affected by the amount of light than voltage. Voltage is affected more by temperature

I know what you mean, but your statement is contradicting basic Physics concepts now !

Voltage is effected by temperature but it is an indirect resultant change, not directly responsible, and current is directly influenced by either resistance or voltage which indirectly as you say is effected by things like radiation levels unless that is there are new laws recently discovered - lol

Just looking at his peak figs so far he peaked at 1pm with 3.615w @ 39.6deg at 253.1Vac Grid current - that's abit too high for my liking but you maybe right and it may reduce as the mths go by, but he seriously needs to watch this IMO ??

 

[moggy1968]

I think we might be ssaying the same thing in a different way danesol:smilielol5:

voltage is affected by the amount of irradiation but, not as much as current and the temperature of the panels in the summer will reduce their voltage output. at the moment, when sunlight is bright with little atmospheric polution but the air is cold panel voltage is likely to be at it's highest. After May it will probably be less.
The systems we have done I have figures for tended to max ot mar/april last year, not in the summer and thats because of the effect of temp on voltage.

basic physics is lab based, actual real life is not.
The laws of physics tell us a rock will fall at the same speed as a feather, but in real life they don't because of the presence of other factors!

 

[danesol]

basic physics is lab based, actual real life is not.
The laws of physics tell us a rock will fall at the same speed as a feather, but in real life they don't because of the presence of other factors!

They do in a vacuum, plus terminal velocity of all items falling to earth not acted upon via other forces will be the same :tounge_smile:

Now lets get back to Ohms Law ...... lol