Solar PV Hints, Tips & Troubleshooting

Mickeroo · 28-01-2021 2:33pm

gomamochi1 wrote: »

Just got this from myenergie about the solar pv/ battery/ eddi conundrum that I am having=

'If it is an AC coupled battery we can work along side it, with it being a DC battery, we cannot measure the input and output of the battery. Therefore you have to clamp after the inverter meaning there is no way to differentiate between PV and DC Batteries for the eddi,

There is lots of people worldwide with a hybrid PV system with a DC battery, However we currently do not have a way of measuring the battery independently to the PV. '

There should be setting in the zappi called Export Margin or something like that. Set that to 50w and it will ensure it only diverts when there is at least 50w being exported to the grid. This will stop it drawing on the battery.

Apologies, missed where you said eddi rather than zappi there, I would expect the eddi has a similar setting though.

slave1 · 28-01-2021 3:04pm

gomamochi1 wrote: »

Just got this from myenergie about the solar pv/ battery/ eddi conundrum that I am having=

'If it is an AC coupled battery we can work along side it, with it being a DC battery, we cannot measure the input and output of the battery. Therefore you have to clamp after the inverter meaning there is no way to differentiate between PV and DC Batteries for the eddi,

There is lots of people worldwide with a hybrid PV system with a DC battery, However we currently do not have a way of measuring the battery independently to the PV. '

I've become disillusioned with my hybrid/battery setup, getting it gutted next week and the hybrid and battery are going with just conventional inverter in it's place.
If you have a low demand household and want to have a net zero Grid day then perhaps fine with ~8kWh of batteries but the economics are not there...

championc · 28-01-2021 3:07pm

The Eddi and Zappi work in totally different ways and should not be confused.

The Eddi only reads the GRID connection, and grabs any excess which may be heading for export. So with an Eddi, the production source of this excess is immaterial. So the Eddi looks to keep your export at ZERO.

The Zappi (in ECO+ Mode) is designed to divert excess coming from a Solar PV Inverter, once that excess exceeds 1.4kW. The Zappi (in ECO+ mode) has no real interest in the Grid.

If you have both and we're generating 1.3kW of excess, it would go to the Eddi irrespective of whether the Zappi had priority over it, until such time as that excess becomes 1.4kW

If anyone has an AC coupled battery, a Zappi can be set to Avoid battery Charge or Drain.

You night be able to "fudge" a Hybrid Inverter by setting a lower charge rate meaning that the onboard hybrid battery could be charging while also giving excess for the likes of a Zappi or Eddi

slave1 · 28-01-2021 3:08pm

gomamochi1 wrote: »

Just got this from myenergie about the solar pv/ battery/ eddi conundrum that I am having=

'If it is an AC coupled battery we can work along side it, with it being a DC battery, we cannot measure the input and output of the battery. Therefore you have to clamp after the inverter meaning there is no way to differentiate between PV and DC Batteries for the eddi,

There is lots of people worldwide with a hybrid PV system with a DC battery, However we currently do not have a way of measuring the battery independently to the PV. '

MyEnergi are constantly working on the software side of the house, you can micro manage your devices to match your flexible energy tariff now, not much of an advantage here with just day/night rate but in the future with Ocotpus like setup I'll certainly have the car plugged in and be paid to charge it up thank you very much!

randombar · 28-01-2021 3:16pm

slave1 wrote: »

I've become disillusioned with my hybrid/battery setup, getting it gutted next week and the hybrid and battery are going with just conventional inverter in it's place.
If you have a low demand household and want to have a net zero Grid day then perhaps fine with ~8kWh of batteries but the economics are not there...

Snap, if I was to go again I'd go with a standard inverter and look to put in a separate AC to DC converter / BMS. Gives the required control needed to manage eddi, zappi etc.

championc · 28-01-2021 3:20pm

slave1 wrote: »

If you have a low demand household and want to have a net zero Grid day then perhaps fine with ~8kWh of batteries but the economics are not there...

I believe they are there, once you get Lithium batteries, and St the right price. I had nearly 18kw of lead-acids but only 50% is usable, and after that, it's difficult to charge up beyond about 85%. So you're down to 35% of your initial 18 !!!

Get LiFePO4's and you can use 80% safely. So I've 10kW and can use the guts of 8kw. And they charge at whatever full rate you can, right up to about 95%

So get them at the right money is key

slave1 · 28-01-2021 3:37pm

Right money is correct, you have an enviable AliExpress setup alright but the BMS and self install (not to mention storage requirement) would be well beyond the vast majority of the population.
I'm investing my ill gotten gains into more panels rather than storage, I also have both EDDI to divert into hot water and two EV's on the driveway so I suppose batteries make no sense for me but I was willing to try them out for a while to see

gomamochi1 · 28-01-2021 4:16pm

championc wrote: »

The Eddi and Zappi work in totally different ways and should not be confused.

The Eddi only reads the GRID connection, and grabs any excess which may be heading for export. So with an Eddi, the production source of this excess is immaterial. So the Eddi looks to keep your export at ZERO.

The Zappi (in ECO+ Mode) is designed to divert excess coming from a Solar PV Inverter, once that excess exceeds 1.4kW. The Zappi (in ECO+ mode) has no real interest in the Grid.

If you have both and we're generating 1.3kW of excess, it would go to the Eddi irrespective of whether the Zappi had priority over it, until such time as that excess becomes 1.4kW

If anyone has an AC coupled battery, a Zappi can be set to Avoid battery Charge or Drain.

You night be able to "fudge" a Hybrid Inverter by setting a lower charge rate meaning that the onboard hybrid battery could be charging while also giving excess for the likes of a Zappi or Eddi

The zappi is the master on my system and the eddi and hub are slaves so I presume if i set export margin limits to 50w as above mentioned it should help/ stop the drain of battery in the mornings when there is no solar pv and battery is discharging to gaff after being charged overnight.
Is there any way to limit the hybrid solis inverter from discharging the battery to the grid- i presume i have fudged some setting on the solis with my messing around that has caused this to happen? As others dont seem to have the same prob as me with the same setup? Thanks

championc · 28-01-2021 8:35pm

slave1 wrote: »

Right money is correct, you have an enviable AliExpress setup alright but the BMS and self install (not to mention storage requirement) would be well beyond the vast majority of the population.

If people are thinking the same way as you, I can guarantee you that you are WAY overthinking things.

You simply connect all 16 battery cells together with the busbars provided in the kit. That's simply using a 14mm spanner or socket on the M8 bolts supplied. After that, you take a positive Red cable off one end of the battery string and a negative Black cable off the other end and connect them into your inverter. And if you get a BMS, you simply connect the Black wire to the negative end of the battery string and connect each positive battery terminal along the string, starting at the Negative end

That's it !!! 10kW of battery storage for about €1500 tops

gomamochi1 wrote: »

The zappi is the master on my system and the eddi and hub are slaves so I presume if i set export margin limits to 50w as above mentioned it should help/ stop the drain of battery in the mornings when there is no solar pv and battery is discharging to gaff after being charged overnight.
Is there any way to limit the hybrid solis inverter from discharging the battery to the grid- i presume i have fudged some setting on the solis with my messing around that has caused this to happen? As others dont seem to have the same prob as me with the same setup? Thanks

Again, maybe you are misunderstanding stuff. The Export Margin is an attempt to continuously export an amount out to the grid - the reason being that if you turn on a medium or large using device, your inverter may not reach as quickly to the increased load and may initially start importing power from the grid before your inverter catches up. So if your inverter is somewhat over producing, the overproduction (50w) will start to pick up the initial additional load

What time are you having discharge of your batteries that you are trying to prevent ? If it is pre 08:00, but you want to run off night rate until 08:00, then you should stay charging until 08:00. The minute to stop charging, the batteries will start discharging if there is no Solar power to satisfy the load required.

randombar · 29-01-2021 12:19pm

championc wrote: »

If people are thinking the same way as you, I can guarantee you that you are WAY overthinking things.

You simply connect all 16 battery cells together with the busbars provided in the kit. That's simply using a 14mm spanner or socket on the M8 bolts supplied. After that, you take a positive Red cable off one end of the battery string and a negative Black cable off the other end and connect them into your inverter. And if you get a BMS, you simply connect the Black wire to the negative end of the battery string and connect each positive battery terminal along the string, starting at the Negative end

That's it !!! 10kW of battery storage for about €1500 tops

Again, maybe you are misunderstanding stuff. The Export Margin is an attempt to continuously export an amount out to the grid - the reason being that if you turn on a medium or large using device, your inverter may not reach as quickly to the increased load and may initially start importing power from the grid before your inverter catches up. So if your inverter is somewhat over producing, the overproduction (50w) will start to pick up the initial additional load

What time are you having discharge of your batteries that you are trying to prevent ? If it is pre 08:00, but you want to run off night rate until 08:00, then you should stay charging until 08:00. The minute to stop charging, the batteries will start discharging if there is no Solar power to satisfy the load required.

Are you using a separate DC to AC converter for battery storage etc. or hybrid inverter?

unkel · 29-01-2021 1:06pm

GaryCocs wrote: »

Are you using a separate DC to AC converter for battery storage etc. or hybrid inverter?

Separate. Sofar ME3000SP.

Several forum regulars have the same battery inverter, graememk and myself included.

mp3guy · 29-01-2021 1:14pm

How do these DIY setups function in power cut situations?

unkel · 29-01-2021 1:18pm

How do you mean DIY setups? It's not like we've fabricated our own inverters, LOL! Sofar ME3000SP is fully certified for use in Ireland and, as pretty much any other inverter on the market, has anti-islanding built in. So grid down -> no power out of it

Except of course it does have a completely separate emergency power supply point that provides 3kW of power to a completely separate circuit. I have connected an outside external waterproof socket to this. It will work as long as there is juice in your batteries...

I have 3 main ways of getting AC power in or around my house in the event of a powercut:

1. Sofar EPS connected to my home attached battery (4kWh usable) - 3kW
2. Pure sine wave inverter connected to my car's battery (77kWh usable) - 600W
3. Cheap chinese inverter connected to my bike's battery (0.7kWh usable) - 1500W

mp3guy · 29-01-2021 1:35pm

unkel wrote: »

Except of course it does have a completely separate emergency power supply point that provides 3kW of power to a completely separate circuit. I have connected an outside external waterproof socket to this. It will work as long as there is juice in your batteries...

Does your PV still function to provide power then also or just battery?

unkel · 29-01-2021 2:05pm

No. My normal solar PV inverter (a Solis) also has anti-islanding just like any other inverter, so it will stop working when the grid is down.

mp3guy · 29-01-2021 2:12pm

unkel wrote: »

No. My normal solar PV inverter (a Solis) also has anti-islanding just like any other inverter, so it will stop working when the grid is down.

So grid goes down, you can run off what you have in battery storage, but if it's sunny you can't charge the battery or use the immediate PV power?

Probably a rare enough occasion for most, but an awful shame on that one day a year.

unkel · 29-01-2021 2:23pm

mp3guy wrote: »

So grid goes down, you can run off what you have in battery storage, but if it's sunny you can't charge the battery or use the immediate PV power?

Yep

mp3guy wrote: »

Probably a rare enough occasion for most, but an awful shame on that one day a year.

Very rare here in Dublin, but as I posted once the battery is empty, I still have my car's battery, which can run the essentials of my house for several weeks

We did have a powercut last year that lasted more than just 10-15 minutes (the first one in about a decade) and I tested all 3 systems and they were working. Was working from home from my workstation in the attic, powered from my car via a 25m extension cable and then I fried some stuff in my air fryer powered by my ebike battery

graememk · 29-01-2021 3:15pm

unkel wrote: »

Yep

Very rare here in Dublin, but as I posted once the battery is empty, I still have my car's battery, which can run the essentials of my house for several weeks

We did have a powercut last year that lasted more than just 10-15 minutes (the first one in about a decade) and I tested all 3 systems and they were working. Was working from home from my workstation in the attic, powered from my car via a 25m extension cable and then I fried some stuff in my air fryer powered by my ebike battery

I must figure out out much the DC -DC converter can handle on the eNiro.. could be a useful supplement..

where I am, we rarely get powercuts, 99% of the time its storm damage.
and then its back on within a few hrs.

I think we had one or 2 last year.

unkel · 29-01-2021 3:24pm

graememk wrote: »

I must figure out out much the DC -DC converter can handle on the eNiro.. could be a useful supplement..

Absolutely. Most are powerful enough. The one in the Tesla is 2.5kW

The car has jump posts just behind the front nose cone (which you can take off by hand, which is handy). These are part of a 50A fused circuit onto the 12V lead acid aux battery. Hence why I'm connecting to this circuit, using just a 600W inverter, don't want to pop that fuse (online vid showing it pop at just over 90A)

If I had bigger needs, I would piggy back on the direct connection between DC-DC converter and the 12V battery. You'd need 200A cables though, but the thought of pulling 2.5kW from your massive car battery is very sweet

mp3guy · 01-02-2021 12:23pm

unkel wrote: »

The car has jump posts just behind the front nose cone (which you can take off by hand, which is handy). These are part of a 50A fused circuit onto the 12V lead acid aux battery. Hence why I'm connecting to this circuit, using just a 600W inverter, don't want to pop that fuse (online vid showing it pop at just over 90A)

Which inverter do you use?

unkel · 01-02-2021 1:32pm

This one:

Linky

I paid £88 with free UK shipping (plus parcel motel costs, so a touch over €100 all in), but they seem to have gone up in price

Was a combination of it being a half decent make, reasonable price and pure sine wave (for charging lithium battery packs). There are far better inverters out there, but didn't want to dig any deeper for something I would rarely use. Would be handy for going camping though, can bring microwave oven or travel kettle, etc.

phester28 · 01-02-2021 1:59pm

unkel wrote: »

This one:

Linky

I paid £88 with free UK shipping (plus parcel motel costs, so a touch over €100 all in), but they seem to have gone up in price

Was a combination of it being a half decent make, reasonable price and pure sine wave (for charging lithium battery packs). There are far better inverters out there, but didn't want to dig any deeper for something I would rarely use. Would be handy for going camping though, can bring microwave oven or travel kettle, etc.

My Experience of China pure sine wave inverters is that they are good with one MAJOR issue. Expect them to be able to deliver about half the constant current rated and never go near the peak or surge as it may end in smoke. Of course there may be the exception.

Have watched knurlgnar24 on youtube for years. Good channel to introduce inverter repair

My 300W 24V is fine at a 200W restive load but the cooling fan will run about 95% of the time so its struggling even at that load to keep the fets (heat sync) cool.

gomamochi1 · 01-02-2021 2:03pm

unkel wrote: »

This one:

Linky

I paid £88 with free UK shipping (plus parcel motel costs, so a touch over €100 all in), but they seem to have gone up in price

Was a combination of it being a half decent make, reasonable price and pure sine wave (for charging lithium battery packs). There are far better inverters out there, but didn't want to dig any deeper for something I would rarely use. Would be handy for going camping though, can bring microwave oven or travel kettle, etc.

these maybe used more than you think as we are prob heading camping again this year with a spare leiseure battery in the van !

phester28 · 01-02-2021 4:32pm

gomamochi1 wrote: »

these maybe used more than you think as we are prob heading camping again this year with a spare leiseure battery in the van !

Anyone using these needs to understand what VA actually means. For example a 800W microwave draws about 13-1400 watts from the grid. Where as a travel kettle is a restive load so will be exactly what is written on the appliance.

Anything with a motor such as a fridge also has a huge inrush current and so you may find a fridge that has a 150w rating needs a starting rating of over 5-8 times that

phester28 · 04-02-2021 5:28pm

quick question on Solis inverters.

Mine shows 20W generation when the thing is in standby. (dark outside) etc. Is this typical as it will mess up the annual generation figures. By counting the 20w for the 18hours of the day (winter) that it is effectively shut down.

unkel · 04-02-2021 6:05pm

On the inverter itself? That's strange, mine just "switches off" - doesn't display anything once generation goes down to zero (when dark). Can't remember exactly but the stand by consumption is very low according to the specs, maybe about 1-2W

graememk · 04-02-2021 7:04pm

unkel wrote: »

On the inverter itself? That's strange, mine just "switches off" - doesn't display anything once generation goes down to zero (when dark). Can't remember exactly but the stand by consumption is very low according to the specs, maybe about 1-2W

Mine just switched off too.

But! If you go in the app it might still show the last reading it received. It's not recording 20w all night

phester28 · 04-02-2021 7:12pm

That could be it. I haven't checked on the inverter itself. Just the app. It shows 20W always. The graph ceases at 6pm so that could just mean all is well and the last value is what is continually displayed

unkel · 04-02-2021 7:16pm

I wouldn't trust an app over what it says on the inverter itself

graememk · 04-02-2021 8:52pm

phester28 wrote: »

That could be it. I haven't checked on the inverter itself. Just the app. It shows 20W always. The graph ceases at 6pm so that could just mean all is well and the last value is what is continually displayed

Like this (it's showing offline.. well it is dark)

Solar PV Hints, Tips & Troubleshooting

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