Kilowatt Power

Hi all,

I wanted to share our recent experience with a Deye firmware update that went wrong and how Deye support resolved it. Hopefully this helps someone in a similar situation.

---

Date: 2026/04/28
Model: Deye SUN-8K-SG01LP1-EU

---

🔵 Original Firmware (Before Update)
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
HMI：VC.3.4.D
MAIN_1：V3.8.8.1
MAIN_2：V0.7.1.7

---

🔴 Failed Firmware Update - Resulted in COMM Error
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：1400-0017
HMI：0000-C384
LCD Type：0000

What happened: Deye remotely pushed a firmware update from their end. After the update, the inverter displayed a persistent COMM error and would not recover. We followed the standard troubleshooting steps of switching off PV, AC and battery power, waiting 5-10 minutes then restarting but the error would not clear.

We contacted Deye Support at [email protected] with the serial number, firmware details and photos of the LCD screen. They responded promptly and pushed a corrected firmware remotely.

---

✅ Latest Firmware - After COMM Error Resolution by Deye Support
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：6027-1724
HMI：0000-C384
LCD Type：0000

---

The inverter is now back to normal operation. Full credit to the Deye support team for resolving this quickly.

If you encounter a similar COMM error after a remote firmware update, my advice is:
1. Don't panic and don't replace the control board just yet. Check the forums first.
2. Contact Deye Support directly at [email protected] with your SN and firmware screenshots.
3. They can push a corrected firmware remotely to resolve the issue.

Hope this helps someone!

Date: 2026/04/28
Model: Deye SUN-8K-SG01LP1-EU
---
Original Firmware (Before Update)
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
HMI：VC.3.4.D
MAIN_1：V3.8.8.1
MAIN_2：V0.7.1.7
---
Failed Firmware Update — Resulted in COMM Error
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：1400-0017
HMI：0000-C384
LCD Type：0000
---
Latest Firmware — After COMM Error Resolution by Deye Support
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：6027-1724
HMI：0000-C384
LCD Type：0000

Hi all,

I wanted to share our recent experience with a Deye firmware update that went wrong and how Deye support resolved it. Hopefully this helps someone in a similar situation.

---

Date: 2026/04/28
Model: Deye SUN-8K-SG01LP1-EU

---

🔵 Original Firmware (Before Update)
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
HMI：VC.3.4.D
MAIN_1：V3.8.8.1
MAIN_2：V0.7.1.7

---

🔴 Failed Firmware Update - Resulted in COMM Error
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：1400-0017
HMI：0000-C384
LCD Type：0000

What happened: Deye remotely pushed a firmware update from their end. After the update, the inverter displayed a persistent COMM error and would not recover. We followed the standard troubleshooting steps of switching off PV, AC and battery power, waiting 5-10 minutes then restarting but the error would not clear.

We contacted Deye Support at [email protected] with the serial number, firmware details and photos of the LCD screen. They responded promptly and pushed a corrected firmware remotely.

---

✅ Latest Firmware - After COMM Error Resolution by Deye Support
Protocol Version：V0.2.0.1
Lithium Battery Version Number：V0.0.0.0
MAIN：6027-1724
HMI：0000-C384
LCD Type：0000

---

The inverter is now back to normal operation. Full credit to the Deye support team for resolving this quickly.

If you encounter a similar COMM error after a remote firmware update, my advice is:
1. Don't panic and don't replace the control board just yet. Check the forums first.
2. Contact Deye Support directly at [email protected] with your SN and firmware screenshots.
3. They can push a corrected firmware remotely to resolve the issue.

Hope this helps someone!

What is Inside My Inverter?
Hello Everyone
This thread is Made To Help you know the Inverter internals, Considering It A Good Judgment of its quality, Spec, and true capability in comparison between them.
In this thread, you will find pictures that contain inverters Model, MPPT Specs (Some of it), and weight
this information is gathered from Inverters Datasheets and Main Boards Sellers (MPP Solar Distributor) and Repair Videos and will add more Model when good intel found or Provided.
- From the included Picture (Considering it the True Voltronic design not a cheap Clone) :
1- it is noted that the VM III 4kw, 6kw Similar to the Original VM III with an extra Aluminum Cooler on the MPPT and One Less Bus Cap
2- VM II 5.6kw Almost Equal to VM III 6kw (Without The Extra Aluminum Cooler on the MPPT) But use different UI (VM II's) and Less Software Features
3- King II 5kw is similar to MKS IV 5.6kw but the MKS is A higher end Model (Extra Components)
4- VM II 5k Premium Close to VM III 6kw Twin but Have a separate MPPT Board (Preferd Among Technicians) and Extra Bus Cap
5- Felicity Solar Inverters Uses Different Design Than Voltronic (And Have Way Less Models) Closer In Design to Mks Models Components Wise (Separate SPS Board + Not Negative Liner Voltage Regulator + RTC battery on the Main Cpu Board Like Mks)
The Thread contains these 24v and 48v Models:
Felicity Solar: IVEM 3024 - IVEM 5048
Voltronic: King II 5kw - MKS IV 5.6kw - VM II 3k Premium - VM II 5k Premium - VM II Twin 5.6kw - VM III 4kw Twin - VM III 6kw Twin - VM III 5kW

Note: Voltronic Mix and Match and rerelease same model name with different/extra features Example (VM II: they added Twin, Premium, Premium Lite, Elite, Premium Plus).
Note: There is alot of Cheaply made inverter with same looks and models with cut down components and cheap semi conductors this Thread dose not factor those Models in the comparison and not responsible for any Misguiding from cheap clones.

Expert Feedback is Welcomed

Adding More Models (2025-5-16):
MPS-V 3500w Plus this model is a modded Voltronic clone (Probably from Sumry Factories) with separate MPPT, and have 12 Mosfet on the input section with VMII interface (Better than the Voltronic VMIII 4kw Models Component wise (more Bus Caps and Input Mosfets and one more transformer).

The easiest way i have found is to just limit the battery power in the system work mode for the particular time. I have mine set to 2000w for the evening so it cant deplete the battery as fast when using the oven or geyser.

Yes, your assumption is correct. With the CTs placed at position (B) before the automatic servo voltage stabilizer, they measure only the current flowing from the grid. During a power outage, when the mains contactor is open and the generator contactor is closed, the CTs at position (B) will read zero current because no grid power is being drawn.
As a result, the inverter, guided by the Chint DTSU666 smart meter’s zero-export logic, will not push power back to the grid or the generator alternator. The inverter will detect no grid demand (since CTs show zero current) and either reduce its output to match local load requirements or stop exporting entirely, depending on its configuration. This prevents the inverter from supplying power to the generator, avoiding potential inefficiencies or instability.

The most appropriate location for installing CTs for the Chint DTSU666 smart meter for zero-export management is (B) Before the automatic servo voltage stabilizer. This placement ensures the CTs measure only grid power, enabling accurate zero-export control without interference from the stabilizer or diesel generator. It avoids the drawback of option (A), where DG power could disrupt inverter operation, and is likely more practical than (C) due to typical wiring layouts.
Option (A) is less suitable because it measures both grid and DG power, which can mislead the inverter’s zero-export logic during grid outages. Your concern about the DG running at <30% load highlights this issue, as the inverter may attempt to supply power to the DG, reducing efficiency or causing instability.
Options (B) and (C) both focus on grid power, making them better for zero-export management. The choice between them depends on practical considerations (e.g., wiring access, space). Since the servo stabilizer primarily affects voltage, not current, placing CTs before the stabilizer (B) is typically more practical and standard, as it aligns with common inverter setups where CTs are installed close to the grid input.

I've had great success at a student hostel with the 4A version of these current limiting protective devices. Culprits get disconnected for 60s whenever the load exceeds 920W.

Yes. 3 CT coils are installed with the same polarity on each phase. Had to change the direction of all 3 CT coils when I realised energy was being exported to the grid. Shall get pictures when I next visit the site.

The 15kW load runs from 8am to 4pm. Maximum solar production is at 12 noon when the sun is directly overhead.
North East happens to be the building azimuth angle. I would however want to believe that direction becomes less significant as the tilt angle approaches 0°. I read somewhere that  a horizontal roof has a tilt angle of 0° and an azimuth angle of 0°
I want to believe so. It's correctly displaying V, A, %THD, Hz, PF, kW, kVAr, kVA, kW and import/export kWh and kVArh. Most importantly it's communicating with the inverter and preventing grid feed-in. Shall peruse the manual once more and go through all settings just to be sure.

The mounting structure is fixed. The 5° tilt angle was to allow for rain to naturally clean the panels. Having said that, I'll get the panels hosed down once again to completely eliminate the possibility of dust curtailing production.
Wasn't measured. Shall try getting readings with the clamp meter thermocouple probe at high noon.

I know my suggestion was a long shot and the efficiency shouldn't be as low as yours. Thanks for that efficiency curve. Haven't seen it before.
Do you have some sort of a monitoring app which can provide a full day V/A curve for each MPPT? That should at least tell you if you are lacking on the volts or amps. Something like this Solarman graph from my SunSynk inverter. I have ran a full load for the whole day and your site is pretty much doing the same from 8AM to 4PM. 

 

The 3-phase string inverter doesn't have the exact menu options as the hybrid but enabling unlimited export is still worth a try. I doubt if the utility meter will enter into tamper mode as a result. The worst that can happen is for the meter to count exported energy forward. 
The string inverter has options for a limiter or smart meter. Opted for the Eastron CT smart meter.
Thanks. 
SUN-25K-G03 is a grid-tied inverter. Everything is on the grid side, after the main incomer MCCB. 

The grid standard does not specify the maximum size . It normally just sets the limits on min and max volts at which point the inverters must disconnect. The standard also sets the frequency limits of operation. That is normally set by the grid supply authority. By using more panels mean you are increasing the voltage so for the same load the amps will be lower. Further more panels as indicated would just mean less power from the grid. 
Not sure which grid standard one would apply in the country where the system is installed but don't see a problem using the ZA grid standard or the EU standard. AUS also fine but I think they are stricter on the volts and freq limits. Their standard might also include a system where they have control over the inverter to switch it off if grid ties are moving the network into an unstable region. 
G83. 3 or G100 standard should  also be fine I think. Have not looked at other standards. 
My 2c on what I can remember which at times is dangerous. 
 

Some clarity and information about wiring and using of SPD'S in DC and AC curcuits. We had a discussion and concerns as where and how the SPD'S should be wired in solar combiners and AC db boards. This article in LikkedIn presented by ONCYY tier1 producer of dc and solar protection devices.
https://www.linkedin.com/pulse/why-surge-protector-preceded-fuse-circuit-breaker-onccy

I've had great success at a student hostel with the 4A version of these current limiting protective devices. Culprits get disconnected for 60s whenever the load exceeds 920W.

I've had great success at a student hostel with the 4A version of these current limiting protective devices. Culprits get disconnected for 60s whenever the load exceeds 920W.

Correct statement and to just add to it,  it is essential that cables between battery and inverter needs to be short as possible as the de-rating with longer cables is actually very real. I use these formula to determine cable size in mm².
Current/3 = Cable size in mm² up to 5 meters. For example: if the current is 200A, then the cable needs to be:  200/3 = 66mm² for 5 meters so closest cable size is 70mm².

I've had great success at a student hostel with the 4A version of these current limiting protective devices. Culprits get disconnected for 60s whenever the load exceeds 920W.

Yes, but the Axpert machines can only entertain the Pylon RS485. This is opposed to Deye/SS that can entertain Pylon Canbus as well. 

It looks to be a Seplos BMS in your battery so google that.

Off the top of my head, your PS4 power supply cannot "ride through" the 20ms transfer time of your SNA 5K inverter.
Not sure but try changing the AC input voltage range setting from APL to UPS to reduce the transfer time from 20ms to <15ms. 

 

Off the top of my head, your PS4 power supply cannot "ride through" the 20ms transfer time of your SNA 5K inverter.
Not sure but try changing the AC input voltage range setting from APL to UPS to reduce the transfer time from 20ms to <15ms.