So now I have a solar PV system how do I make the most of it???

Hungerdunger

don0301 wrote: »

theres one thing I'm not interested in

the dribble you come out with

Drivel ????

jamesingram

zeupater wrote: »

Cue Zeupater ...
. have you been in the loft with the OWL and checked the Power reading against the calibrated inverter yet ? .
Z

Don have you tried this ,(surprised if you haven't) You're obviously interested in monitoring your system , this would give you a feel of the accuracy of your OWL. rather than trying to do it on paper.
alternatively via Graham's gen. meter method.

I share Z's views placing the sensor inside the CU might upset the readings a bit. It may be (or could be put) in the trunking below the pv main ac isolator.

Still I was surprised by your 3.5kW max ac output the other day.
hence why I'm questioning the accuracy of your Owl setup.
though I agree you do have a good orientation/pitch for this time of year. with lower temperatures improving the situation.

my system 4.32 kW array (3.68kW TIC/DNC)
didn't get above 2.5kW today but generated 11.7kWh ,
hasn't been above 2,5kW all week
(SE , 2400@35deg / 1920@22.5deg (1 hour shading at peak on smaller array) not best set up for max. output at the moment.

cheers

don0301

jamesingram wrote: »

Don have you tried this ,(surprised if you haven't) You're obviously interested in monitoring your system , this would give you a feel of the accuracy of your OWL. rather than trying to do it on paper.
alternatively via Graham's gen. meter method.

I share Z's views placing the sensor inside the CU might upset the readings a bit. It may be (or could be put) in the trunking below the pv main ac isolator.

Still I was surprised by your 3.5kW max ac output the other day.
hence why I'm questioning the accuracy of your Owl setup.
though I agree you do have a good orientation/pitch for this time of year. with lower temperatures improving the situation.

my system 4.32 kW array (3.68kW TIC/DNC)
didn't get above 2.5kW today but generated 11.7kWh ,
hasn't been above 2,5kW all week
(SE , 2400@35deg / 1920@22.5deg (1 hour shading at peak on smaller array) not best set up for max. output at the moment.

cheers

hi James

I'm very aware of the accuracy of my monitor.

In fact I'm the only person who has put maths to "paper" ref. post 1102. to explain my findings.

I accept my maths is a bit "fag packet" in so much as I guessed the day hours that my system is not/or low generating, which i declared in that post. Yet, I still feel my maths is there or thereabouts.

I'm still waiting for my main protaganist to prove my maths wrong with actual figures, rather than words....cue zuepater?

The fact is my maths puts my monitor at approx. 6% overreading. as near as damn it, within the stated error of 5% by the manufacturer (caveat depending on current measured, but if considered overall during a 24 hour period a reasonable assumption).

regarding z's assumption about the readings being "affected" within the CU, I would like to say this (which I've said before elsewhere on this forum I'm sure, but will repeat)

at first, when i noticed the 113W constant reading at night or non generation, I considered the inverter might be faulty ( 113W at my setting of 230V on the owl monitor equates to almost exactly 0.5A, according to the destruction manual my inverter should pull 0.23W!). the installers returned, and with a much more accurate ring sensing device, found exactly the same reading i did with my owl. so not the owl then....

they then wrote to the manufacturer of the inverter for advice, who replied asking me to switch off all fuses at the CU, except the inverter one, note the house electric meter reading outside, then leave overnight, and note in the morning. after 13 hours overnight, the meter reading had not moved even .01. so no problem with the inverter drawing power incorrectly then! or generating at night!

i then removed the clamp from the "live feed" and replaced in exact same position but not connected to wire. 0 reading. so no outside influence affecting it! i then removed the sensor, and 0 reading! so presumably nothing wrong with the owl monitor calibration.

so, the explanation from the manufacturer that "messy" sine wave at very low current badly affects the owl (and any other ring sensing) monitor seems robust!

all this is fairly irrelevant tho, because i know this nuance, as per post 1102, i factored it and removed it from the equation.

as to my 3.5kW reading, it wasn't constant but it was real. i consider it an overreading of 5% therefore my best guess is it (my inverter) was actually producing about 3.325kW. hardly much difference.

as an aside, today i pretty much had 2.8-2.9kW (owl monitor) constantly from about 09:30 to 14:30 or so today. I produced 16.4kWh (as measured by my gen meter) so my monitor really isn't that far out when no night/no generation error.

I've stated many times i use the owl for reference, not as a "meter" as z puts, as i quickly realised its limitations.

this has been a long post, so i reserve right to edit it in the future, but think (most) of what I've put makes sense. wake up, you at the back!

jamesingram

don0301 wrote: »

hi James
i then removed the clamp from the "live feed" and replaced in exact same position but not connected to wire. 0 reading. so no outside influence affecting it! i then removed the sensor, and 0 reading!

I presume you mean you did this with all mcb on and normal house loads running? to show no interference from these loads

Perfectly fair , you know the potential errors of your monitor .
You use it to get a feel for generation without having to go to into the loft. Simple enough
Still be tempted to hold it (the owl) up next to the inverter just to see
what the difference is though:)

cheers

don0301

jamesingram wrote: »

I presume you mean you did this with all mcb on and normal house loads running? to show no interference from these loads

Perfectly fair , you know the potential errors of your monitor .
You use it to get a feel for generation without having to go to into the loft. Simple enough
Still be tempted to hold it (the owl) up next to the inverter just to see
what the difference is though:)

cheers

yup, all done with the installers there, as we tried to figure what was going on.

regarding the difference at for say 3.5kW reading, i would be gobsmacked if it was more than 5% error. willing to take bets

to date i dont have a ladder to get in the loft, (enough bets pay for one tho ) so I'm afraid I fail there

tbh I dont care, i know my gen meter reading, i have the owl for idea of generation, and chucking stuff on for free

I'm happy, its certain other people who aren't

don0301

Cardew wrote: »

your? or you are? or you're?

i? or I?

pertinent? or pertinent.?

funny how you never correct graham's many more errors

but then you don't admit to your own errors, so I *wink* guess I *wink* shouldn't be surprised

https://forums.moneysavingexpert.com/discussion/3738661

but glad your picking up on the game, fun isn't it?

don0301

Originally Posted by zeupater
Cue Zeupater ...

.... But the issue is that if the voltage was set correctly at least the Power displayed would be accurate and the accumulated energy incorrect as opposed to both being wrong .... have you been in the loft with the OWL and checked the Power reading against the calibrated inverter yet ? ..... remember, you have already stated that the accumulated Energy reading is available on the calibrated TGM, so why the obsession with using the OWL as a meter as opposed to a monitor as most others do ??

I have absolutely no idea where the installers placed the sensor within the Don's consumer unit, but as previously posted, I have experienced similar increased inaccuracy when our sensor is close to the henley block, this likely being a combination of field disruption caused by the block itself & partially sensing the field generated by the current from the load in the house ..... I would therefore anticipate that there would be an equivalent effect from having a similar sensor fitted within the house consumer unit ....

What would I do ? ... simply compare the Power on the inverter to the Power on the OWL and set the OWL's voltage parameter to whatever would give the closest reading, or get the installers back and have them change the wiring configuration to provide the ability to fit the sensor(s) outside the consumer unit. Whichever way, I'd take the manufacturers advice ... "OWL Monitors are intended as educational aids in the understanding of the cost of operating electrical appliances in the home, to stimulate behavioural change in how we use electricity in the home, and not to replace your accurate electricity revenue meter." (http://www.theowl.com/index.php?page...isplay-monitor) ... and not attempt to use it as a meter ....

HTH
Z

zeupater wrote: »

It's extremely likely that it probably would be the case that 'both ways' would be the same way considering that if there is a difference between the readings then it could be due to the voltage being set incorrectly and most who are reading this would probably accept that to be the case .... have you tried it yet to see if it helps ?? ....

HTH
Z

your "Sir Humphrey Appleby", right?

link:

http://en.wikipedia.org/wiki/Humphrey_Appleby

tip: try maths instead of bullsh1t

Martyn1981

grahamc2003 wrote: »

Ignoring all your nonsense and just addressing this point ... well isn't it very easy to get an accurate estimation of the generated power from the generation meter at its 0.1kWh resolution?

If he's generating 3.5kW, then that's just 1.714 minutes to wait for the meter to increment 0.1kwh (I'd appreciate a maths whizz like you or Don to check the maths please), so no need to wait 15 or 20 minutes (don't know what was going through your head with that one, unless you think Don is pulling your leg). So instead of Don spending about 18 hours on these boards, he could take say a 5 minute break around lunchtime when the sun is strong and his owl is reading 3.5kw, and measure how long 2 or 3 0.1kwh increments take.

Seriously! That's your solution, seriously?

So rather than Don comparing 6 hours of cumulate data, he should time his TGM (assuming he has decimal places - I think he has, not sure) and hope that the instantaneous kW's stay steady (no clouds etc), and then work backwards. Why not simply use the 2 months of data he has? Surely he should aim for long term accuracy, not short term errors?

Plus as far as I can see it, Don is spending most of his time on here 'dancing' with you, and having to point out info that has already been discussed, but for some reason you were still unaware off. As I read these posts, Don is quite confident in the readings (+/-5%), it was you that stirred this issue up, trying to claim that the figures were untrue (why?). Well since then several other people have posted data that support high generation when steep panel angles are involved.

If you let us PV'ers play happily, rather than trying to spoil the game all the time, we wouldn't have to keep going into overtime, would we?

Smile, today should be sunny.

Mart.

Martyn1981

jamesingram wrote: »

I presume you mean you did this with all mcb on and normal house loads running? to show no interference from these loads

Perfectly fair , you know the potential errors of your monitor .
You use it to get a feel for generation without having to go to into the loft. Simple enough
Still be tempted to hold it (the owl) up next to the inverter just to see
what the difference is though:)

cheers

Hiya James, that's an interesting idea, and something I tried when I got the Optismart. Slightly tricky as I've got 2 inverters, and one of them has an alternating screen, so a quick bit of mental arithmetic needed.

My TGM is reading higher than the inverters by 1%. Apparently not unusual, as the manuals for both inverters (SMA's) state that their readings are for information only, not as meters. I've heard of differences as large as 5% between inverters and TGM's.

Interested to know what others have found. My TGM is still 1% higher than the 5+ month totals on my inverter screens.

Mart.

HalloweenJack

hmmm dont your invertors switch off at night/ no output? mine does...