Ecoworthy 5K (SRNE) sanity check. Can it grid-feed?

[SolarUKWM]

Could someone give me a sanity check here?

I have an Ecoworthy 5000 (SRNE HF clone) which makes _no_ mention of being able to feed energy back into the grid.

To be clear, I don't need or want that facility. But ...

The manual makes no mention of that being a feature. It says it has "back filling protection" which sounds good. Although, that could mean "it won't grid-feed if the grid goes away (anti-islanding, thumbs up!). But if the grid is there, sure, I'll feed into that ... (umm?)"

Does this model have the ability to grid-export?

[It gets longer here, puzzle along with me!]

My first doubt crept in when I found "setting 34". This is not in the manual, but exists on the unit. On other SRNE inverters, says "In Bypass mode, what to do with excess PV energy: DISable (nothing), LOD -- use it to run the load alongside grid, GRD -- feed it to the grid". Ummm? I went with "LOD" as the best option, and thought, well, at least it can't export to grid, might as well run the load.

My second doubt crept in when _something_ triggered my in-home-display for the electricity meter to stop saying "xxx W used now" (on a 0-10kW dial scale) and change to "xxx being imported now" (on a Negative-Something-watts - 0 - 10kW dial scale). As if it had detected "oh, exporting are we? Let me represent that!"

My smart-meter shows no export, although it could have been a _tiny_ export that woke it up. Not enough to meter as "1 unit" yet, but enough to alert it.

The conditions I _think_ this happened under were :-

1) Unit in bypass mode, running loads.
2) Battery charging from (grid and PV mix) from SOC 80% to 100% (Loads + charger absorbing all PV)
3) Charging stopped (PV now supplying more watts than the load used)
4) A little excess PV may have gone to grid _despite_ LOD setting.

I can understand the DIS/LOD/GRD logic: If there is PV left over -- in DIS, do nothing, it's wasted. In LOD -- allow _only_ enough to exactly balance GRID draw, no more. In GRD -- allow everything. In this way, it can help support the load (until the grid is not being used at all), or it can support the load AND export to the grid.

I think I've seen in Dave/EEVBlog's videos where this balancing act of trying to keep export at zero can fail by small amounts, as the system tries to measure and react to changes. "Mostly zero".

But this is all theoretical, and predicated on one thing -- that this device is even capable OF exporting. And I didn't think it was ... ?

Either that, or the internal current transformer for "grid" measurement is reading wrong, and it didn't know it _was_ exporting. (I already have issues with Solar Assistant reporting 'grid' readings that are significantly higher than I _know_ them to be, so I hope that's not indicating a problem where the inverter really _is_ mis-measuring!)

So, it thought it was "pushing back" against a 900W grid load, when in fact the load was only 350W. Shoulda stopped pushing at 350W of PV (you are running the load single handed!) but in fact would have pushed all the way to 900W (running the load and exporting).

If anyone can make sense of that lot, please chip in. Not sure quite what to test or measure at this point, or whether I'm chasing something that is a figment of something's imagination.

 

[ricardocello]

Eco 5000 is described as a Hybrid inverter, so to me, that means it can operate in parallel with the grid.
Which means it can back-feed, even if you do not want to.
“alongside grid” means it can back-feed to grid.

You have just described the problem with so-called “zero-export” using real world cause and effect. Well done!
There is nothing wrong with the CTs, it is physically impossible to react fast enough when loads switch off to prevent back feed.

 

[ricardocello]

As if it had detected "oh, exporting are we?

So, what will your power provider do now that they know? Is that an issue in the UK?

 

[ricardocello]

See
Post in thread 'Eco-Worthy Hybrid inverter'
https://diysolarforum.com/threads/eco-worthy-hybrid-inverter.74746/post-1213109

 

[SolarUKWM]

Eco 5000 is described as a Hybrid inverter, so to me, that means it can operate in parallel with the grid.

In "parallel with the grid" is okay -- and although I didn't know it could do that, I soon realised it was an option (when you have grid, but no batteries OR batteries are full, then PV + Grid can run loads -- cool!).

That is (in my head) a one-way thing. Two sources, driving one load.

Of course, what has now occurred to me is that in bypass mode, where load L+N terminals are connected pretty much to grid L+N terminals (subject to internal relays, current transformers) then what is good for the LOAD could end being sent to the grid.

so-called “zero-export” using real world cause and effect. Well done!

Damn ... not ideal.

There is nothing wrong with the CTs,

It's a faint possibility. Because in bypass mode, with the battery NOT charging and no PV production, GRID power should be identical to LOAD power, right?

But I get readings like PV: 0W, Battery -40W (the inverter self-use), Grid: 900W, Load: 400W ... (for avoidance of doubt, 900W is definitely nonsense, home-meter reports 460W, which is 400W of load through the EcoWorthy and 60W of other loads the EcoWorthy can't see) ... and I've reported this to Solar Assistant as a possible bug with reading the inverter, but not heard back yet.

I see reports of Grid draw that are anywhere from twice to four times the actual value. Haven't nailed down a pattern yet. Solar Assistant have the logs/GUI pictures to look at.

what will your power provider do now that they know?

No idea. I don't have an export agreement in place, or a tariff that recognizes exporting as something I should get paid for, so I'd rather not export!I If there were other loads on within the house, then it would just offset that and not show up at the meter. But once it's running the loads on the EcoWorthy, _and_ the 60-odd watts of idle-draw elsewhere that is on the "grid" side, every watt above that could potentially export.

I'll set it back to 34 = DIS and hope for the best. Rather an important feature to _not mention_ in the manual!!

 

[ricardocello]

It's a faint possibility. Because in bypass mode, with the battery NOT charging and no PV production, GRID power should be identical to LOAD power, right?

Right. Something isn’t measuring correctly.

No idea. I don't have an export agreement in place, or a tariff that recognizes exporting as something I should get paid for, so I'd rather not export!I If there were other loads on within the house, then it would just offset that and not show up at the meter. But once it's running the loads on the EcoWorthy, _and_ the 60-odd watts of idle-draw elsewhere that is on the "grid" side, every watt above that could potentially export.

I'll set it back to 34 = DIS and hope for the best. Rather an important feature to _not mention_ in the manual!!

Best case is that they won’t care about your minimal back-feed.

 

[SolarUKWM]

Post in thread 'Eco-Worthy Hybrid inverter'

Useful, thanks! I think that's the situation, right there.

The "old" meter I had may have not liked it, because it was a standard digital meter with no export facility. So it might see it as fault/tampering to spin-the-wheels backward. Even if it was an LCD digital one! Under that arrangement, you had to have a separate EXPORT meter fitted for solar etc.

The "new" meter (smart meter) has separate accounting for imported and exported power, because it's a thing nowadays. I still can't see any actual exported power, shows 0.000 kVa/kW, so it appears nothing got exported of note.

 

[SolarUKWM]

back-feed.

Although I'm trying to use the correct terminology here ... "exporting" is good. "Back-feeding" is dangerous.

The latter is when an inverter goes rogue (or is wired by a lunatic) and attempts to drive the grid side when there is no grid signal.

I'd rather be on the "accidental export" side than the other.

 

[ricardocello]

Useful, thanks! I think that's the situation, right there.

See post #30 in that thread.

The "old" meter I had may have not liked it, because it was a standard digital meter with no export facility. So it might see it as fault/tampering to spin-the-wheels backward. Even if it was an LCD digital one! Under that arrangement, you had to have a separate EXPORT meter fitted for solar etc.

The "new" meter (smart meter) has separate accounting for imported and exported power, because it's a thing nowadays. I still can't see any actual exported power, shows 0.000 kVa/kW, so it appears nothing got exported of note.

You might see around 1 kWh export over a month.

 

[SolarUKWM]

Ah yes, the mysterious option 34 is mentioned in that thread too.

L

Post in thread 'Eco-Worthy Hybrid inverter'

Sep 24, 2024

Thank you for your quick response, but what I am asking is : has anyone here who installed this system get contacted by the power company complaining about a feedback to the grid? Just want to make sure what Eco-Worthy has said is true, because if it is then the smart meter will not get a feedback power and thus the power company will not complain.

I have two of these units, I have them both running as single units , I have no issue with feedback power ( although there is an option from the user manual #34/to feeding extra power into the grid but I never use it I don’t if it’s...

• Lener

• 

 

[ricardocello]

Although I'm trying to use the correct terminology here ... "exporting" is good. "Back-feeding" is dangerous.

The latter is when an inverter goes rogue (or is wired by a lunatic) and attempts to drive the grid side when there is no grid signal.

I'd rather be on the "accidental export" side than the other.

You know, I’m going to start using “accidental export”, you make a good point.
The vendors don’t call it that, unfortunately.

 

[42OhmsPA]

Newer firmware on the 10kW (ASP) units from SRNE got rid of setting 34. Not sure if it also applies to the HYP (E W 5kW).
Are you sure you have the HF clone and not the HYP?

Could always ask @Bill Young from Eco Worthy for clarity.

 

[SolarUKWM]

Newer firmware on the 10kW (ASP) units from SRNE got rid of setting 34. Not sure if it also applies to the HYP (E W 5kW).
Are you sure you have the HF clone and not the HYP?

Could always ask @Bill Young from Eco Worthy for clarity.

Definitely the HF. Last picture in the thread is like mine, but mine is orange! Breaker on the side, TWO RS485's, on-off moves over to the left. Otherwise, same.

HYP has connectors for parallel operation (stacking for more current, split-phase/three-phase etc) and mine has blank-plates over all that.

https://diysolarforum.com/attachments/1000012504-jpg.259487/

Link to actual product

5000W 48V Pure Sine Wave Inverter | Off Grid Essential

Power off-grid life with a 5000W pure sine wave inverter. Features include 80A controller, high efficiency, and advanced protection.

uk.eco-worthy.com

 

[Mattb4]

Couple of quick points. There is no excess PV if you are only feeding loads and battery. Loads pull power. This should be your default setting for 34 (Dis). This does not allow any export. The other selection of hybrid (Mix LOD) and (On Grid) allows the inverter to operate in parallel with grid and anytime you are in parallel current can flow either direction. The grid is a huge load and will grab whatever it can if you are connected.

 

[SolarUKWM]

There is no excess PV if you are only feeding loads and battery. Loads pull power.

Hi -- in this case the PV production was showing on SolarAssistant as higher than load consumption. Battery draws nothing, (fully charged) -- so the excess PV must have been going to the grid for a short time. Not much, and not for long ...

Agreed if it's on DIS then that shouldn't be a problem, and that's where it's going to be staying!

 

[SolarUKWM]

anytime you are in parallel current can flow either direction.

I think this is what I came up against (theory vs. practice)

In theory: LOD means current won't flow back to grid because the unit will sense the to-from grid flow, and hold back so as to NOT send to grid. In practice: It could miss a little here and there.

Never selected To GRID, as that looks like trouble to me!

 

[SolarUKWM]

The vendors don’t call it that, unfortunately.

On the other hand, "backfilling" is when you use your mini-digger to put soil into the trench you dug. I've never heard it used outside of that context, until I saw the ECOWorthy manual.

 

[42OhmsPA]

Hi -- in this case the PV production was showing on SolarAssistant as higher than load consumption. Battery draws nothing, (fully charged) -- so the excess PV must have been going to the grid for a short time. Not much, and not for long ...

Agreed if it's on DIS then that shouldn't be a problem, and that's where it's going to be staying!

How much higher? It won't be 1:1 due to efficiency losses.

I ran my 10kW with grid connected for about a year, option 34 disabled, and never had an issue.

 

[SolarUKWM]

How much higher? It won't be 1:1 due to efficiency losses.

Note: Currently the panels are not in their final position, so are not producing as they should, and are the bare minimum to tickle the MPPT's input. More to be installed, and all in the proper spot, soon.

I'm used to seeing PV production exceed load on a sunny day. The excess usually goes into the battery, because I'm in off-grid (Solar-Battery-Utility) mode. So the battery draw goes down, through zero, and then starts charging instead. Then the reverse as the production drops off. Normal.

This was different, because I was in bypass mode (Grid) at that point _and_ the battery had charged up, so was no longer electrically there to take any PV at all. Then it got sunny.

Peak looks like 578W PV and 280W Load. Elsewhere, 500W/290W or 540W/328W

Even allowing for losses, that means some power went somewhere else. About 40-60W could export from the EcoWorthy's point of view and be eaten by "house loads" which are not protected by it. The smart meter would not view that as export, just a reduction in load from 60W to ... 0W.

After that, there's nowhere to go, so actual export-to-grid is the only option.

Although the In-Home-Device says 0.0 kWh exported, the smart meter says 000000 kWh/kVA exported, so it must have been a very small amount. Solar Assistant agrees, 0.0 export.

 

[Wolfpack7483]

Newer firmware on the 10kW (ASP) units from SRNE got rid of setting 34. Not sure if it also applies to the HYP (E W 5kW).
Are you sure you have the HF clone and not the HYP?

Could always ask @Bill Young from Eco Worthy for clarity.

I've got the HYP rebadge. Installed it in 2/24. Option 34 is available, although I've left it disabled. Just checked, and I do have the option to change it.

 

[SolarUKWM]

Grid: 900W, Load: 400W ... (for avoidance of doubt, 900W is definitely nonsense, home-meter reports 460W, which is 400W of load through the EcoWorthy and 60W of other loads the EcoWorthy can't see) ... and I've reported this to Solar Assistant as a possible bug with reading the inverter, but not heard back yet.

On the "there's nothing wrong with the CT's" point. Here's a graph of Actual Grid Draw (as measured by Smart Meter/In Home Device) against Reported Grid Draw. Above 1.1kW it's fairly accurate, about 80W over-reported, I'd call that good enough.

Below 1.1kW, increasingly over-reported. I've not seen it report below around 950W -- other than when there is _no_ load, where 0 = 0. As you'd hope it would.

I have no way of knowing if 1) This is a faulty sensor that can't properly get down to zero because of mis-reading, 2) This is Solar Assistant mis-interpreting a MODBUS register (log law vs linear, or something daft like split-precision reporting for low loads vs higher loads)

I cannot compare Solar Assistant numbers to the ECOWorthy to see if they agree/disagree, because the inverter user interface does not show _Grid_ current and power. Only Load, PV, Battery in-out.

If the sensor genuinely is misreading like that, it would make a nonsense of trying to balance PV and grid export to be "zero", as the inverter will think it can push back against e.g. a 980W draw (that doesn't exist) and end up exporting.

 

[ricardocello]

On the "there's nothing wrong with the CT's" point. Here's a graph of Actual Grid Draw (as measured by Smart Meter/In Home Device) against Reported Grid Draw. Above 1.1kW it's fairly accurate, about 80W over-reported, I'd call that good enough.

CTs are just coils. They typically have an accuracy rating like 0.5%.

Below 1.1kW, increasingly over-reported. I've not seen it report below around 950W -- other than when there is _no_ load, where 0 = 0. As you'd hope it would.

This chart is great, but the low end looks asymptotic to 980W, as you’ve said.
I hope that the device isn’t actually drawing 980W.

I have no way of knowing if 1) This is a faulty sensor that can't properly get down to zero because of mis-reading, 2) This is Solar Assistant mis-interpreting a MODBUS register (log law vs linear, or something daft like split-precision reporting for low loads vs higher loads)

Inverter firmware bug most likely.
Do we have official MODbus documentation for this inverter?
Perhaps they reverse engineered it in SA.

Edit: Found this:

https://solar-thailand.co.th/pdf/SRNE-MODBUS.pdf

Don’t see anything appropriate in there, unfortunately.
See next post.

I cannot compare Solar Assistant numbers to the ECOWorthy to see if they agree/disagree, because the inverter user interface does not show _Grid_ current and power. Only Load, PV, Battery in-out.

If the sensor genuinely is misreading like that, it would make a nonsense of trying to balance PV and grid export to be "zero", as the inverter will think it can push back against e.g. a 980W draw (that doesn't exist) and end up exporting.

Agreed, this will mess up the grid export balancing.

 

[ricardocello]

Ok, found this on scribd, more registers.

SRNE Hybrid Solar Inverter MODBUS Protocol V1 7 | PDF | Computer Engineering | Computing

This document specifies the Modbus communication protocol for energy storage inverters. It defines the serial port parameters as 9600 baud rate, 8 data bits, no parity. The protocol uses a master-slave structure with a universal address of FFH. Frame formats are provided for reading and writing...

www.scribd.com

Based on this list, I believe they only have CTs on the load side, not the grid side.

Which means they have to calculate grid power from PV, battery, and load power.
The calculation is obviously not being done correctly.

I’m guessing here, I don’t own any SRNE devices, others will need to dig deeper.

 

[SolarUKWM]

I hope that the device isn’t actually drawing 980W.

It really isn't. I would notice that. Current draw is not the approx 4A it would need to be -- and the utility co's smart meter would have something to say about it.

only have CTs on the load side, not the grid side.

That would be interesting to sort out. The numbers definitely don't add up. For disconnected/dark PV and no battery charging (full) ... Source: (Grid in) should equal Loads.

In bypass these should match -- the inverter seems to run off the battery (-40W) in this situation, not grid.

Thanks for looking though.

Firmware is Apr 7 2023, Primary V6.56, Secondary V2.01, Protocol V1.07 as supplied on new unit early Feb 2025.

Edit: I found a MODBUS/SRNE document v1.3 that references Register 214: "Grid Side Current: For 2nd Gen Machines" ?

 

[marionw]

It really isn't. I would notice that. Current draw is not the approx 4A it would need to be -- and the utility co's smart meter would have something to say about it.


That would be interesting to sort out. The numbers definitely don't add up. For disconnected/dark PV and no battery charging (full) ... Source: (Grid in) should equal Loads.

In bypass these should match -- the inverter seems to run off the battery (-40W) in this situation, not grid.

Thanks for looking though.

Firmware is Apr 7 2023, Primary V6.56, Secondary V2.01, Protocol V1.07 as supplied on new unit early Feb 2025.

Edit: I found a MODBUS/SRNE document v1.3 that references Register 214: "Grid Side Current: For 2nd Gen Machines" ?

0x213 is Grid Voltage Phase A
0x214 is Grid Current Phase A
0x215 is Grid Frequency
0x22A is Grid Voltage Phase B
0x238 is Grid Current Phase B
0x23A is Grid Active Power Phase A
0x23B is Grid Active Power Phase B
0x23D is Grid Apparent Power Phase A
0x23E is Grid Apparent Power Phase A