Solar PV Hints, Tips & Troubleshooting

graememk

https://www.boards.ie/discussion/comment/121248983#Comment_121248983

You can, sign up for a esb network account and you can see it. You don't need to be on a smart plan.

Having a battery is great, but with the high fit it's a lot harder to justify it. That could also spread out the peaks from the hob etc.

Mellor

https://www.boards.ie/discussion/comment/121249556#Comment_121249556

Costs aside, a battery is obvious the way to optimise you power. You'd want to be storing power to cover all of the peak usage, and then use the rest for day usage. But then there's that pesky payback time.

delmonte4

i want to connect a 2nd Dyness BX51100 battery to an existing setup and just want to clarify if I need to switch off my Solis Hybrid inverter when doing so, or will switching off the breaker between the inverter and battery suffice? Has anyone any experience adding an additional battery to a Solis inverter?

graememk

https://www.boards.ie/discussion/comment/121297126#Comment_121297126

Always best to turn everything off, Solar, Battery isolator, AC.

delmonte4

does The inverter pick up where it left off or need to be reconfigured settings wise do you know?

graememk

https://www.boards.ie/discussion/comment/121297899#Comment_121297899

Picks up where it left off.

Geeyfds53573

Hi all,

I've been away for a few weeks and have 2 more weeks until im back.

I set inverter to Feed in priority as I always do. It's a Solis 5 with calbs seplos. The battery has drained but I keep seeing 186B2 every few hours shows 0% or 15% (inverter discharge limit) SOC depending when I look at it

Alarm message: Can communication failure.

Followed by no battery alarm

Do you think it is ok to leave the errors popping up for the next two weeks I Dont have much choice unless Solis could pull the plugremotely

My feeling is the bms is protecting battery and I Dont see any discharge happening

Ummagumma_78

I have been looking to expand my system. I have 15 x 340W JA panels. I got on to original supplier and they have told me that they can’t source these panels anymore. They have said I would need panels to be same manufacturer and within 10-15W of current panels. Is this accurate on both the manufacturer and power output requirement. Bit frustrating as its difficult to get another supplier to support an array installed by a different company

10-10-20

https://www.boards.ie/discussion/comment/121353319#Comment_121353319

Hi! You need to match or better the Impp (current at max power point) and then look at the Vmpp across the string and ensure that it doesn't exceed the MPPT limit on the inverter.

REC solar have a good guide on it, but the rule about matching the W to within 10 to 15W isn't the best rule to work off (in my opinion).

I personally think that you could mix and match the manufacturers in the string fine. Beyond voltage and wattage the other main differences between the manufacturers is the sensitivity of the cells to the varying light levels, so there might be some minor differences in low-light situations. Questionable whether that would be an issue or not as newer panels tend to be more sensitive (or productive) to lower light levels than the older panels anyway.

Anyway, here's the REC guide.

https://www.recgroup.com/sites/default/files/documents/module_mismatch_en.pdf

Ummagumma_78

Thanks for this. That’s really useful information. Array is split across 2 strings (9 +6) and I am planning on adding 4-5 panels to the 9 panel string. I have a Solis 5K hybrid inverter so from looking at the inverter data sheet I don’t see an issue with exceeding the MPPT limit with that configuration.

Interesting about the manufacturers. I got the feeling that maybe the original installer wasn’t too interested in the work (Enniskillen company and I’m based in Cork). I’ll look in to other installers in the Munster region but if anyone has a recommendation would appreciate it

pjordan

So here's a puzzler which some of ye might be able to shed light on for me as I'm almost descending into the rabbit hole of conspiracy theories to figure it out...

So I've had my Solar PV system installed for 3 years now (4.8kw system with 4.4 kw of battery storage, Solis inverter and Eddi water heating diverter). From day 1 it has been (afaik) configured to supplement mains power, then divert to Eddi or battery charge and finally to FIT. I have day/night rate, so I also use night rate electric to charge the battery at night.

And so to the puzzler....

Prior to installation of the PV system I was using in the region of 6000 units/kwh's of electricty PA (6300 in 2018, 6200 in 2019 and 6100 in 2020) charged at flat day rate. Since installation of the PV system my panels have produced 3566 units in 2021, 4114 in 2022 and currently headed for about 3800 units for 2023. However, my annual consumption from the grid for these corrosponding years per my electricty bills are 5800 for 2021, 5600 in 2022 and projected for about 4800 this year.

So where is my PV generation going or what could account for an apparent discreptancy of almost 3000 kw per annum? Or am I misreading something here? There is nothing notable that I can think of that might account for such a huge increase in consumption per annum. Initially, in the first year before the introduction of the FIT, I used time a second immersion in the garage to switch on daily for an hour or so when PV generation was at it's max, but I discontinued that when FIT came along and in the last year I've been credited about €400 for FIT. My Solis is configured to charge the battery between midnight and 7am on night tarrif. Accordingly my ratio of day/night consumption works out at about 30:70. As for potential big consumption items, We have an electric oven but don't use it any more than we would have before PV, We have a tumble dryer but only use it occasionally and again no major change in last 3 years. In winter our oil boiler comes on to heat underfloor during night and also to heat the hot water so Eddi is only really a top up/boost during daylight. In summer this is reduced to one half hour blast of boiler for hot water only early in morning. I've been working from home 3 days per week since Covid with 2 monitors going and a blast of central heating and a desk lamp occasionally but again nothing notably excessive. I've even installed Wifi switches for lights and TV/standby electrical items, etc during the night which switch off between 1am and 8am.

Now this is where the "conspiracy theory" possibilities come in. Since some time in the summer after the installation I've started noticing a low hum when I'm lying in bed at night. I've even tried turning off the main power switch but it persists. I'm just wondering is it possible that my meter is not properly configured for PV production and is somehow not accuretely measuring my actual consumption or the "hum" somehow indicates some sort of ongoing "leakage" from my system back into the mains, and I've been incorrectly showing over consumption for the past 3 years? Or perhaps my whole system is just configured incorrectly so that I'm over consuming electricty at peak? Either way it has me stumped and I'm just wondering am I missing something here? Be delighted to hear any thoughts or even queries by PM (I can forward any Excel sheets I've prepped to record all this)

con747

https://www.boards.ie/discussion/comment/121384626#Comment_121384626

Possibly issues with a ct clamp maybe? Others can advise you how to check it if it is.

Jonathan

https://www.boards.ie/discussion/comment/121384626#Comment_121384626

Do you have a smart day night meter yet? That will allow you to download a HDF file an see your usage (grid import/export) in 30min intervals.

If you don't, you can use an app to determine your realtime usage. Bear in mind that 3,000kWh/year a year is only a 350W base load. It racks up pretty quickly when left on 24/7.

championc

Take a day, any day, and look at the GRID graph from the MyEnergi App.

And count up the kWh that you exported over the 12 months.

The question is whether you are exporting when you expected to, or wanted to.

You could be charging your battery and dumping it straight back out to the grid..

You could have a backwards MyEnergi grid clamp, and so be heating the Eddi whenever you are importing power.

The graph will reveal everything. Data never lies !!!

pjordan

https://www.boards.ie/discussion/comment/121385915#Comment_121385915

1302kWh exported to grid so far this year

graememk

https://www.boards.ie/discussion/comment/121389187#Comment_121389187

When did your smart meter go in?

testtech05

Guys a bit of a random one maybe someone has experience with...

A friend had an install done previously by a supplier who he was very happy with. 5kw Huawei inverter but no battery at the time. He now wants to add a battery and BMS but his original supplier seems to be quite a bit more expensive with the battery set up than some competitors.

His question is if other suppliers will go near it knowing someone else installed? I'm sure he will ring around during the week but I said I would throw it in here aswell in case anyone has experience.

pjordan

https://www.boards.ie/discussion/comment/121389316#Comment_121389316

It didn't, I'm still waiting on installation of a day/night smart meter. That export stat is from my Solis cloud report. I've detailed daily and monthly stats for PV power (Self Use, Charging Power and Energy Exported)and Consumed Power (Self Sufficiency, Battery Discharge and Power Imported) but I'm having difficulty intrepreting or spotting anything obvious or indicative in those stats that might show specific high consumption in a particular area

dumb_parade

https://www.boards.ie/discussion/comment/121389433#Comment_121389433

Is he willing to source the battery and bms himself. The install could be done by any electrician. I added a second battery to my system myself.

testtech05

https://www.boards.ie/discussion/comment/121392101#Comment_121392101

I hadnt even thought of this being an option for him, good shout. I will let him know. Thanks a lot.

DC999

https://www.boards.ie/discussion/comment/121392116#Comment_121392116

@HotSwap installed his own Huawei compatible battery + bms afaik. He might chime in here

HotSwap

https://www.boards.ie/discussion/comment/121392504#Comment_121392504

You don’t need an electrician; it’s just a DC cable and a data cable between the BMS and inverter. everything you need comes in the box. Just go to your local kelehers and tell them what you need.

kevinr7213

Hey, I'm looking for some battery advice, please. I am getting my solar PV installed on December 5th. System 5.66KW E/W split with a hybrid inverter, no battery. I have been reading through this thread and found it very informative, so thanks for that. Many of ye have built your own batterys and have very impressive systems. Im looking for a pre-built battery that I can hook up to the system myself. I dont have time at the moment to attempt to build a battery. I have seen Fogstar mentioned previously in the thread; at the moment, they have a black friday sale and have a 5kw battery for £999.

Specs are as folows:

https://www.fogstar.co.uk/collections/solar-battery-storage/products/topband-rack-battery-51-2v-100ah

Any thoughts on this, any advice appreciated. Thanks

samdeluxjones

https://www.boards.ie/discussion/comment/121385890#Comment_121385890

How exactly does that app work? You need the smart meter but do you also need a smart tariff? Can you add multiple meters?

Jonathan

https://www.boards.ie/discussion/comment/121411632#Comment_121411632

Nothing fancy. Just converts the 1000imp/kWh LED pulses into instantaneous power. Works with non-smart digital meters too.

Rob99

https://www.boards.ie/discussion/comment/121401185#Comment_121401185

I really rate the Fogstar stuff and the customer service responses when I had questions.

I was intending to get 6 of their rack batteries myself but when I discovered they would not physically fit in my loft I decided instead to build a couple of Seplos 280L kits.

If you can, I would get a rack cabinet for them as well, keeps everything nice and neat.

kevinr7213

https://www.boards.ie/discussion/comment/121412188#Comment_121412188

Thanks for the reply, appreciate it.

munsterfan2

Adding a second inverter, 12 more panels so I will have a 3.5kw & 2.5kw inverters, current inverter is hybrid, wired to fireman switch. Is there any reason I cant just connect a second fireman switch off this wiring as per image

Jonathan

https://www.boards.ie/discussion/comment/121435107#Comment_121435107

Check the model of the fireman switch. It might have a second pair of unused inputs/outputs.. Though with 12 panels you might be looking to go with two strings, in which case, your original idea sounds fine.

SD_DRACULA

Looks the same as mine so yeah it should have another input, projoy, I have 2 strings of 12 connected to it no problem.

If you look underneath you will see the - and + labelled there.