Problematic Pv Array, Pulling Energy Off Nat Grid.

[Barx]

thye are built to a standard as well and do not register exported solar as energy used. Old stuff clocks backwards, digital meters just break eventually from what I have seen

I have to disagree to an extent. I have numerous so called 'tamper meters' that do indeed measure current either way as import. Thus leading to increased bills. Best way to test is the method mentioned above. When it is nice and sunny, turn all circuits off at consumer unit except solar. See if import meter increases. If the bills have increased as stated then that has nothing to do with any ct clamp and I suspect it is a tamper meter. I have seen at least 20 cases of these.

 

[ProDave]

Re electricity meters.

My own Siemens meter is an odd one. the red light still flashes when it's exporting but the display does not count up.

 

[Rigger]

Barx,  good info, but how can I prove it.

Import Export meter is a Landis+Gyr E110 - 5235A.

Import (t) is showing 1590 Kw and Export ® is showing 506kW.  This meter was installed at the end of March.

Power NI - my electricity supplier - would not accept readings from a analogue meter.

They said it had to be a dual meter that could show OfGen how much I was exporting from my system to the Nat Grid.

My question now is - Is the Landis + Gyr E110 - 5235A a tamper meter - that measures current either way as import, and how can I prove that to Northern Ireland Electricity, and finally to Power NI?

Surely the fact that I have two different readings shows that the meter is working correctly?  Or has the import been reading the export reading too?

I'll be monitoring the system over the next few day anyways.

 

[ProDave]

Confused meter reader?

I had an issue with a rental flat where for about 2 years the meter reader had got the day and night readings for E7 the wrong way round. It took months and 3 meter reader visits to convince them it was wrong.

 

[binky]

ok lets get terminology correct, your solar meter is known as the 'generation meter. it does not measure export, it measures electricty passing through it in one direcion as per any other OFGEM approved meter. If it is wired correctly the inverter will be connected to the left hand side and right hand side connected to your board.

The Landis and Gyr model you mention I've fitted hundreds of, it doesn't clock in reverse - could you imagine the fiddling possible for FiT claims if it did. Now its got dark, check it, your inverter system will be pulling about 10-30watts from the grid in standby mode, yet it won't be clocking anything. When we first started solar work, some people I subbyed in to give hand wired the gen meter the wrong way around, they didn't clock backwards.

 

[Barx]

Binky the 5235a can be configured to read import AND export. I've seen 1 configured this way out of the hundreds of of 5235a's I've seen. It alternates between the 2 reading every few seconds. IF the meter is configured this way I doubt it will be clocking like a tamper meter. So the mystery continues... I would still do the tests above

 

[Rigger]

Binky the 5235a can be configured to read import AND export. I've seen 1 configured this way out of the hundreds of of 5235a's I've seen. It alternates between the 2 reading every few seconds. IF the meter is configured this way I doubt it will be clocking like a tamper meter. So the mystery continues... I would still do the tests above

Barx - True. Although I am considering getting NIE out to check the wiring and configuration of the meter

Blinky - my terminology is correct.  I've got two digital meters - one generation - straight off the PV array - and the inverters are on the roof below each panel - Enphase Micro Inverters. via 3 core cable - live, neutral and earth.  All looks to be connected correctly.

So power comes from PV array - via enphase inverters, into generation meter (currently reading c1870kW).  Then into isolation switch.  Then into consumer unit, circuit breaker.  onto Busbars, and then back to the 5235A import/export digital meter.  Import reading was earlier today 1758kW and denoted with a T.  Export reading was 506 and was denoted with a R.

As Barx says, the unit changes the display every few seconds.

Live and neutral  outputs from 5235A meter appear to be correctly wired in, but can see incoming connections, nor any configurations which I imagine are under the tamper proof panel in the front below the digi readout panel. 

 

[binky]

the 5235A is not an import /export meter, it is a single rate meter without digital pulse.

http://www.landisgyr.co.uk/product/landisgyr-5235/

 

[NozSpark]

So you're missing 1202kWh???

Do you think you might have used it?

 

[Rigger]

Blinky - that's the wrong meter.  You've put up the E100.  Mine is the E110.  Small difference, but it's enough.

 
Mine is in the link below.

http://www.test-meter.co.uk/landis-and-gyr-e110-electricity-meter/

Noz,

I may well have used that extra kW's.  I've been racking my head, and I've been checking my online bills.  The increases started around Dec, when we got the panels installed.

I don't think the meter is at fault, seeing as the new meter was fitted at the end of March, and increases started before then.

So, Dec we got the panels fitted, and I think they are ok to be honest.  What we also got installed was though was a new biomass boiler, which has an electric ignition.

I'm pondering now whether this could have been pulling a lot of current during ignition phases.

The other option was the old analogue meter not being compatible with the solar PV generation, and instead of winding backwards - it has added the PV.

I'll be getting in touch with NIE about the compatibility of the analogue meter today.

 

[NozSpark]

So they think you've imported 1758 units since March? That does seem high...

I'd have thought that you should be exporting more than you import at this time of year... However I know very little about solar pv

 

[binky]

so Trigger it has a pulse (that's the LED on front) still doesn't count backwards.

Now if you want to bandy insults after correctly pointing out what was wrong and offering my extensive PV knowledge **** you

 

[NozSpark]

The meter in the link that you have posted does not measure exported units according to the specification sheet.... as binky has stated

 

[binky]

the clue is in the coding ie the 5235A bit which actually says what it is set for.

 

[Rigger]

Sorry guys - wasn't meaning to offend at all, just a bit of light banter - came across wrong - sorry again. Will use icons a bit more

I've been onto NIE and Power NI about both meters (is it likely that the old analogue meter would count up import and export?)

NIE assure me that the meter is configured for import and export - hence why I am getting two readings import (t) and export ® - but they would say that - wouldn't they.

That link I put up too, also states that those meters are for solar PV.

Type A granted, but why are you saying it's not configured to read import.

All I'm seeing on the diagrams in neutral/live in and neutral live out - with the meter across the live in and live out.

 

[ProDave]

Can you clarify, do you have ONE meter now, or TWO?

The normal set up is one meter for import, that would have been your normal meter before the solar PV was installed. 

Then when the PV was installed it would have had a generation meter, that is NOT an export meter.

They obviously changed your old mechanical disc meter for a digital one. does it have one display or two?  

If just one display is there a button to press to cycle the display function, or does the display cycle between two different readings?

 

[binky]

just cos NIE say it's configured, doesn't mean they are right LOL

check the lettering 5235A / K etc etc

 

[Rigger]

Ok - for clarification.

I have two digital meters.

One is a Yong Tai Long M12 digital meter for reading the generation straight off the the inverter tie-in from the PV array.

At the other side is the Landis + Gyr E110 5235A meter that has been configured to give two readings - t for import and r for export.  it automatically swithces between the T and R meter readings every few seconds.

Binky - point taken about the meter not being configured correctly - we are all human after all.  NIE have been contacted to make sure the meter is configured correctly.

I've also checked some readings from today.

Enphase system says that the panels have generated 15kW today - not great - but not bad.

Checked against the generation meter, and it's not far off really.

Then went and checked import export meter.

readings earlier (9am) were t-1767 and r-507  T=import R = export from Solar PV array.

Reading now (18:20) are t - 1768 and r 515.

So - I'm figuring this means that the meter is not reading both export and import as one, and is able to register the flow direction, and meter it each way.

 

[ProDave]

That looks to me like the metering is working properly.

you have imported 1KWh today which means for part of the day your consumption has exceeded your solar PV generation. Seems quite reasonable.

you have generated 15KWh of which 8KWh was exported, the other 6KWh must have been used within your house.

So I don't see a fault with your installation or metering.

 

[Barx]

This is the manual I read like...

https://www.solartradesales.co.uk/downloads/products/L_and_G_5235_User_ManualBrochure_info.pdf

Same model, different manufacturer stamp. They all share anyways