Deye sun-12k-sg04lp3 inverters in parallel mode drawing power from grid despite fully charged batteries

[domelos16]

Hi everyone,

I'm currently experiencing an issue with my solar setup and could use some advice. I have two SUN-12K-SG04LP3 inverters configured to run in parallel mode. The inverters are set up according to the diagrams provided, and everything seems to be connected properly.

However, I'm noticing that the inverters are drawing power from the grid even though my batteries are fully charged. The amount of power being drawn from the grid varies, but sometimes it goes as high as 1.5KW or even more.

For additional context, all of my devices are connected to the backup load, and I have the "Zero export power" setting configured to 40W. Despite this, the inverters still pull a significant amount of power from the grid. I'm not sure why this is happening or how to correct it.

Has anyone else encountered a similar issue or have any suggestions on how to resolve this?

Thanks in advance for your help!

PS. Currently, I have everything set based on voltage (V). My batteries never discharge below 46V, so according to the "Time of Use" settings, they should discharge down to this voltage level. I do not want to charge the batteries from the grid—only from PV if there is sufficient energy.

I’d also like to add that the power draw from the grid usually begins when it starts getting dark and the energy from the PV is insufficient. Initially, the draw oscillates around 150W per inverter.

Additionally, I am not exceeding the "Max A discharge" limit, so this should not be causing any issues either.

 

[Oldphile]

I had a different problem with my Sol-Ark; idle current was too high. I did a factory reset and problem solved.

 

[XO4001]

Try zero export to CT.

 

[domelos16]

I had a different problem with my Sol-Ark; idle current was too high. I did a factory reset and problem solved.

Hymmm maybe I will try that

Try zero export to CT.

it didn't work either.

More observations:
In the morning when the sun rises, the inverters are charging the battery, supplying the load, and also drawing energy from the grid...
Why is this happening? Shouldn't it work like this: prioritize the load first, then charge the battery, and send any surplus to the grid?

 

[LydMekk]

Please post photos of all your screens on the unit under Battery and Grid etc.

 

[domelos16]

Please post photos of all your screens on the unit under Battery and Grid etc.

 

[domelos16]

I also noticed that for a few seconds, the flow chart shows a negative value in the home load (as I mentioned before, everything is connected as a backup load). I wonder if this is a bug or a correlated issue


But it's usually like that:

 

[shadowmaker]

So how much it draws daily? 1-3kWh?

I think your "zero export power" is little high being 80W. You can use 40W or even 10W, but the lower you set it, the more fluctuating your "zero" power point will be. Mine was 40W and by lowering it to 20W I reduced my daily import power from ~2kWh to ~1,5kWh. Not really important as my yearly usage tend to be ~100MWh few years ago and daily usage could easily be over 600kWh.

 

[Oldphile]

View attachment 237549

I'm seeing the same condition that I had; the delta between power sourced and load is too high.
(1680+949+441) - 2760 = 310 watts. Where is the 310 watts going? The inverter is more efficient than that.
Factory reset worked for me.

 

[shadowmaker]

I have some grid import/export fluctuations as big loads get connected/disconnected all the time, but Deyes seem to try to compensate those so that after importing few hundred W (or a kW or two) in "zero export to CT" mode it sells immediately same exact amount back so on average things stay really close to zero.

If your grid usage is steady ~400W then something might be wrong and factory reset might help like @Oldphile already said.

 

[domelos16]

So how much it draws daily? 1-3kWh?

I think your "zero export power" is little high being 80W. You can use 40W or even 10W, but the lower you set it, the more fluctuating your "zero" power point will be. Mine was 40W and by lowering it to 20W I reduced my daily import power from ~2kWh to ~1,5kWh. Not really important as my yearly usage tend to be ~100MWh few years ago and daily usage could easily be over 600kWh.

About 6-7 kWh.

I just experimented a little with that earlier to see if it made any difference (before, I had set it to 20W).

I'm seeing the same condition that I had; the delta between power sourced and load is too high.
(1680+949+441) - 2760 = 310 watts. Where is the 310 watts going? The inverter is more efficient than that.
Factory reset worked for me.

Okay, I'll give that a try (though I need to learn it first) :D

I have some grid import/export fluctuations as big loads get connected/disconnected all the time, but Deyes seem to try to compensate those so that after importing few hundred W (or a kW or two) in "zero export to CT" mode it sells immediately same exact amount back so on average things stay really close to zero.

If your grid usage is steady ~400W then something might be wrong and factory reset might help like @Oldphile already said.

Yup i will try to reset it.

 

[domelos16]

@Oldphile @shadowmaker Factory reset didn't work. Do you have any other ideas? The flow chart still shows an invalid value after summing.

 

[Oldphile]

@Oldphile @shadowmaker Factory reset didn't work. Do you have any other ideas? The flow chart still shows an invalid value after summing.

I can only guess. Maybe power cycle reset, although that didn't work for me.

 

[shadowmaker]

Do you have external CTs connected next to your utility meter? You need those if using "zero export to CT". If using "zero export to load" those external CTs aren't required, but maybe they could clear your flow chart anomalies (or maybe they are reason for that).

Have you ensured that there is real world daily (even hourly) usage of 6-7kWh? I can see real hourly usage from my PoCo app.

 

[domelos16]

I can only guess. Maybe power cycle reset, although that didn't work for me.

Do you mean to turn off the inverters, wait 30 seconds, and then turn them on again? If so, that didn't work either.

Do you have external CTs connected next to your utility meter? You need those if using "zero export to CT". If using "zero export to load" those external CTs aren't required, but maybe they could clear your flow chart anomalies (or maybe they are reason for that).

Have you ensured that there is real world daily (even hourly) usage of 6-7kWh? I can see real hourly usage from my PoCo app.

I don't have external CTs; I'm using 'zero export to load.' I will try to check my energy meter to see if the data (energy bought) is correct. I will consider installing CTs.

PoCo app?


It's driving me crazy ;/

By the way, what is the idle power consumption for SUN-12K-SG04LP3 inverters? Is it around 100W per inverter?
Is it possible to synchronize the data received from loggers?

 

[Oldphile]

Do you mean to turn off the inverters, wait 30 seconds, and then turn them on again? If so, that didn't work either.


I don't have external CTs; I'm using 'zero export to load.' I will try to check my energy meter to see if the data (energy bought) is correct. I will consider installing CTs.

PoCo app?

View attachment 239188
It's driving me crazy ;/

By the way, what is the idle power consumption for SUN-12K-SG04LP3 inverters? Is it around 100W per inverter?
Is it possible to synchronize the data received from loggers?

A Sol-Ark 15K has a 90 watt spec'd idle current. The 2 inverters appear to be similar in size (watts).

 

[Lener]

Most inverter has an option “output source priority, “ you want to change that option to inverter.

 

[houseofancients]

A Sol-Ark 15K has a 90 watt spec'd idle current. The 2 inverters appear to be similar in size (watts).

The are the same, albeit 3 phase 230/400.

These inverter pull always 20w from the grid to counter reactive loads, and use 60-70w each.
If grid is connected they will always pull self consumption from the grid

 

[shadowmaker]

PoCo app?

Phone/computer application where you can see your consumption/production from your power company (PoCo). They read my utility meter every day multiple times and I can see today's details (one hour intervals) tomorrow morning 8.00 ->.

If using only zero export to load, are you sure you don't have any home loads not connected to your backup load?

I'd connect those external CTs to see what's going on between you and utility. Then you can try "zero export to CT" which need those external CTs to work.

 

[domelos16]

A Sol-Ark 15K has a 90 watt spec'd idle current. The 2 inverters appear to be similar in size (watts).

The are the same, albeit 3 phase 230/400.

These inverter pull always 20w from the grid to counter reactive loads, and use 60-70w each.
If grid is connected they will always pull self consumption from the grid

Ok, then the maximum combined idle power should be around 200W.

Most inverter has an option “output source priority, “ you want to change that option to inverter.

Could you elaborate on that? I can't find a similar option in Deye inverters.

Phone/computer application where you can see your consumption/production from your power company (PoCo). They read my utility meter every day multiple times and I can see today's details (one hour intervals) tomorrow morning 8.00 ->.

If using only zero export to load, are you sure you don't have any home loads not connected to your backup load?

I'd connect those external CTs to see what's going on between you and utility. Then you can try "zero export to CT" which need those external CTs to work.

I don't have access to my utility meter via the app; I need to order it from my power company for installation. For now, I checked it manually and wrote down the numbers. I'll check again tomorrow and compare them with the measurements from the inverters.

Everything is connected as a backup load.

 

[LydMekk]

Still, install your CTs. Turn off the inverter before doing that.
Then report back after a day.
Remember the correct way acc. to the manual.

 

[copec]

Did you want grid peak-shaving enabled?