logo elektroda
logo elektroda
X
logo elektroda
Advanced Search
logo elektroda
Build faster with M5Stack »
Build faster with M5Stack » Stick • Unit • Cardputer
ADVERTISEMENT
Dostępna jest polska wersja

Czy wolisz polską wersję strony elektroda?

Nie, dziękuję Przekieruj mnie tam

SOFAR 8kW PV Installation: Opinions, Durability, Failures & Experiences with Inverters

---Ryba--- 489783 1705
Best answers

How reliable are Sofar inverters for an around-8 kW PV installation, and what problems or failures do users report?

Users report mostly acceptable results: one 6.6KTL-X had no problems for over a year, and another 8.8KTL-X owner said a firmware update to v2.20 removed the old clipping around 8 kW and let the inverter reach full peak power [#18112697] [#18662870] [#19158337] The most common problems in the thread were not outright inverter defects but installation/configuration mistakes: too many panels in one string or the wrong input mode caused DC overvoltage errors such as PvOVP, BusOPV or permanent fault, and the cure was to wire the strings correctly and keep each MPPT within its limits [#18322870] [#18323108] [#18359020] [#18360610] [#18699492] Another recurring issue was grid overvoltage: users saw ID01/Grid OVP shutdowns when mains voltage rose to about 253 V, and one case reached 280 V at the customer side; the inverter was behaving as designed in those cases [#18624602] [#18665849] A few users also mentioned Wi‑Fi/software quirks and awkward warranty handling, with the installer, seller, distributor and Sofar service bouncing responsibility between each other [#18306997] [#18322870] [#18323064] [#18331261] [#18772451] There was at least one real hardware failure report, where an 8.8KTL-X tripped AC overcurrent after about a month and then would not restart, so the unit had to go through warranty [#18771167]
Generated by the language model.
ADVERTISEMENT
Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
Report a violation of the law
Reply | New topic
  • #1141 19926925
    Janusz_kk
    Level 39  
    "radar1967" changed from 6.6 to 8.8kW which according to earlier info there are two different hardware configurations and therefore it does not work because 6.6kW is the maximum for 'small' inverters. For you, the change from 5.5 to 6.6kW may work because it is the same group. But it is good to later verify the currents shown by the inverter with those measured on the network cable.
  • ADVERTISEMENT
  • #1142 19926950
    interside
    Level 14  
    Janusz_kk wrote:
    "radar1967" changed from 6.6 to 8.8kW which according to earlier info there are two different hardware configurations and therefore it does not work because 6.6kW is the maximum for 'small' inverters. For you, the change from 5.5 to 6.6kW may work because it is the same group. But it is good to later verify the currents shown by the inverter with those measured on the network cable.


    Janusz_kk thanks for the answer. I will wait for a stronger sun and see if it changes because today it will not do anything anyway, because the power is within 3kW.
  • #1143 19928089
    radar1967
    Level 11  
    You can safely change the interside to 6.6, then under favorable conditions it will not cut to 5.5, but will use the full power of the panels.
  • ADVERTISEMENT
  • #1144 19932273
    bobrow
    Level 7  
    Hello Society,
    I just joined you a moment ago, although I visited it quite often.
    I have Sofar 11 ktl-x from 2019 with 1.80 soft - so far the installation worked without problems (9.9kWp). However, recently there is a big problem with exceeding the 253V voltage on a sunny day (a large increase in the number of PV installations), and thus my Sofar turns off.
    In general, I am close to trafa and even at night I have an average of about 240VAC, the installation is mounted in the shelter (I took care of everything myself) with a cable of about 45m to the switchboard (5x6mm2).
    I called Tauron, the lady politely offered me to reduce the power of the inverter ... so I skipped this topic.
    At home, I have Domoticz on a Raspberry Pi, so I quickly connected a 2kW heater in the DHW tank with an increase in voltage above 252V for 10 minutes at 9-17. phases (I have no idea what to load these phases ...).
    I wanted to see how the max voltage in the installation increases (briefly) and I tried to choose a different country, e.g. 22 - it turned out that there is a protection programmed (rightly so) Vtenmin = 253V (the last parameter in info)
    I called the Sofar service - apparently the inverter controls the average voltage during 10 minutes, if it exceeds it, it turns off. Of course, when it reaches 264V, it cuts off right away. I will only add that when changing the country (and after turning off the power) it is the same, i.e. Vtenmin.
    Do you have that too? Does a firmware update change this setting?
    Kisses
  • #1145 19932309
    Krzychooo
    Level 16  
    You have a few exits.

    1. Fighting the OSD to lower the voltage on the trafo, but since you are close and the cable is good, first make sure what voltages are at the end of the line.
    If it is also above the norm, then fight. There is a chance. It took me 9 months ... :cry: https://www.elektroda.pl/rtvforum/topic3755521-90.html#19141863

    2. Invest in another heater, or replace the current heater with a 3-phase heater and control it according to phase voltage.

    3. Combinations with transformers at home - not recommended.

    4. The last resort - change the country code in SOFAR, but it requires a service code, I will not help here. And updating the software does not change anything.
  • ADVERTISEMENT
  • #1146 19932312
    krawietz
    Level 16  
    There is a document on the net: "SET OF REQUIREMENTS FOR TYPE A ENERGY GENERATION MODULES, INCLUDING MICROINSTALLATION"
    And in it you have point 11.2 with described protection settings. It shows that the 253V is a 10-minute average value according to EN50160.
    Disconnection time 3s
    Therefore, the question remains whether each excess of 253V, I assume that it should disconnect the inverter for 3s or not.
    With the second value of 264.5V, there is no discussion ... disconnection time 0.2s response time 0.1s.

    Krawietz

    Added after 6 [minutes]:

    Krzychooo wrote:
    Has
    4. The last resort - change the country code in SOFAR, but it requires a service code, I will not help here. And updating the software does not change anything.


    And this probably will not do without a file from Sofar containing voltage settings for a given country.
    Somewhere I read that an inverter once started with the given protection settings, operating for more than a short period of time, remembers these settings permanently and changing the country code does not change much when it comes to the shutdown thresholds. You need to get a file from Sofar with settings and the code to upload them.

    Krawietz
  • #1147 19932330
    Krzychooo
    Level 16  
    krawietz wrote:
    Somewhere I read that an inverter once started with the given protection settings, working longer than some
    a short period of time stores these settings permanently and changing the country code does not change much in terms of the switch-off thresholds.
    You need to get a file from Sofar with settings and the code to upload them

    That's right, probably even in the manual is about it and it probably takes about 2 weeks, but I know that there are service codes that make it possible at any time.
    Otherwise, it would be stupid, because it would block, for example, the equipment used amen. I know it from a guy who does it professionally, but he is an Orthodox and will not give a code, even when drunk ... :sm31: :D
  • #1148 19932359
    Janusz_kk
    Level 39  
    Krzychooo wrote:
    Otherwise, it would be stupid, because it would block the equipment completely.

    After all, it does not block, below 253V the inverter is about you. You have to fight the energy to lower the tap and temporarily, as you were advised, the 3F heater will take care of the problem.
  • #1149 19932392
    bobrow
    Level 7  
    Thanks for the response
    I will ask my neighbors if they have noticed the problem with switching off the inverters at all - maybe if there are several reports from the same town, the power industry will reduce the nap on the hit (although I heard that in principle the mains voltage is normal - only my PV raises the voltage and I have to limit my power...).
    Regarding the 3-phase heater, I have seen one on the Allegro, i.e. 3x2kW - this is a solution (and 300ltr), but it can quickly heat up the water. You can only switch on these phases with exceedances - but if there is too much everywhere, then the bag ...
    Maybe I will try to control the heat pump (Panasonic T-cap 9kW), i.e. the DHW according to Domoticz - I would then control the pump on / off mode, and in the PC I would set the DHW temperature to 55 degrees (without the CO mode it could somehow work). I still have to think about it.
    Kisses
  • #1150 19932460
    Janusz_kk
    Level 39  
    But this PC is probably 1F, so it doesn't solve the problem for you.
  • #1151 19932505
    Krzychooo
    Level 16  
    Temporary overvoltage to the worst phase will also do something, and then other combinations.
    In the worst phase (248-250V) I plugged in all washing machines, dishwashers and everything was hot and there was some effect.


    Janusz_kk wrote:
    After all, it does not block, below 253V the inverter is about you.
    I meant blocking the possibility of this country / standard change, e.g. in the case of selling used equipment.
  • #1152 19932512
    bobrow
    Level 7  
    Janusz_kk wrote:
    But this PC is probably 1F, so it doesn't solve the problem for you.


    I have a three-phase one - only it can handle a 300 ltr tank very quickly (about 30 min)
  • ADVERTISEMENT
  • #1153 19932531
    Krzychooo
    Level 16  
    So control these heaters according to phase voltage and action time.
    I will also be doing it (I have 3x1.5kW) because the neighbor also deigned to put on panels and we are already close to the border, and it's only March ...
    Attachments:
    • SOFAR 8kW PV Installation: Opinions, Durability, Failures & Experiences with Inverters mierniki.jpg (23.56 KB) You must be logged in to download this attachment.
  • #1154 19932540
    bobrow
    Level 7  
    Can you throw a link to this 3x1.5kW heater?
  • #1155 19932567
    Krzychooo
    Level 16  
    My it specifically this one , but you can buy a naked one without a thermostat and security, adding control.
    I had to blow out the thermal protection anyway because it was popping up from time to time.
  • #1156 19932619
    bobrow
    Level 7  
    Krzychooo wrote:


    Thanks for the info - I still have an unusual question: is it possible to power this heater asymmetrically, e.g. with only one phase and in any way to switch on/off the power supply from each tap?
  • #1157 19933035
    Krzychooo
    Level 16  
    Sure, it's a star with an N in the center. I control these heaters in cascade as needed, including 1, 2, or 3 phases.
    Currently, the algorithm is based on date (order rotation), time and demand (tank temperature), but I can see
    that I have to change it to depend on the phase tensions and react to their excessive increase no matter what the rest.
    In general, this approach to the subject of heating and the current algorithm changes like in a kaleidoscope.
    The original assumptions (from a year ago) fell to hell long ago. Life...

    Added after 3 [hours] 8 [minutes]:

    krawietz wrote:
    Therefore, the question remains whether each exceeding of 253V, I assume that it should disconnect the inverter for 3s or not.
    If you ask, I will answer from the autopsy.
    After exceeding 253 by 1V, the inverter works, but already 254 or 255 causes switching off after a while (about 10 seconds),
    but not for 3 seconds, but for more than a minute, because it stops first, then it tries 60 seconds and how it is OK with the voltage
    it also starts in about a minute, i.e. this is how long it takes for him to reach the maximum (at a given moment) power.
    Growth is slow, no spikes.
    It is easy to calculate what losses it gives, because when it is chewed with voltage, it "works" for about 10% of the possibilities, and the effect it gives can be seen below.
    We are talking about version 8.8KTL-X, version SF4ES008, with soft 2.2 set to code 12, i.e. Poland.
    Attachments:
    • SOFAR 8kW PV Installation: Opinions, Durability, Failures & Experiences with Inverters pv-fault-many.jpg (43.97 KB) You must be logged in to download this attachment.
  • #1158 19933576
    krawietz
    Level 16  
    Ok, this explains a bit why mine with the momentary peak at 255 did not cut off. Before and after the jump, the voltages were below 250, and the inverter is asking every 30s.

    tailor
  • #1159 19935242
    bobrow
    Level 7  
    Hello,
    regarding the three-phase heater, I found it on the Allegro for 185 PLN 3x1.5kW 5/4 "stainless steel. I can control Domoticz from 10A relays (they should be enough - about 6.5A per contact, moreover, I will bridge the contacts, it will be 20A per heater). I will electrically secure the system with a switch with a capillary for the power supply contact of the heater's relay contacts (3x25A), plus a Domoticz protection from the ds18b20 sensor (all sensors in the tube in the middle of the tank (300ltr. Stainless steel thermals). safety valve.
    I'm just wondering if 1.5kW will not be too light for a given phase? I will do tests with different loads - this will probably be the best test ...
    Kisses
  • #1160 19935362
    Krzychooo
    Level 16  
    bobrow wrote:
    I'm just wondering if 1.5kW will not be too light for a given phase?

    It depends on several factors, but you can also combine these heaters into one phase, but then there must be some decent system
    protections (serial connection of contacts in NO and NC relays) so as not to connect the phases somewhere ...
    and quick topics on each phase arrival.
    The most important thing is to put the load in phase with the dangerously increasing voltage. It could be done.
  • #1161 19935510
    Janusz_kk
    Level 39  
    All these ideas with heaters and voltage regulation have one significant disadvantage, if your neighbor raises the tension, you will also beat him up :(
    the only sensible way is to measure the direction of the energy flow in the house and only then the heaters can be regulated according to this and the voltage.
  • #1162 19935725
    Krzychooo
    Level 16  
    Janusz_kk wrote:
    if your neighbor raises your tension, you will also beat him up
    But when the neighbor raises the tension, it means that "we" too.
    Direction measurement - OK, but if you want to "load the network", what to do ...? ...
  • #1163 19935747
    Janusz_kk
    Level 39  
    Krzychooo wrote:
    Direction measurement - OK, but if you want to "load the network", what to do ...? ...

    Take enough energy to balance the power consumption at '0', but for that you need ssras and not relays on the heaters.
  • #1164 19935799
    Krzychooo
    Level 16  
    I have SSRs, although in my opinion it is a minor detail (apart from introducing possible disturbances to the network).
    Here the problem, in my opinion, is not to go to "0", but to let the inverter work and give back something, even to the network
    instead of lying fallow.
    So if we raise the voltage for a partnership with a neighbor / s, it is probably better to break it and give the inverter a chance and the heart ...
    Currently, in my opinion, it is better to load 10kWh into the network and receive 8 than nothing.
    I'm wrong?

    More than a year ago, I was making theories about going "0" here, but I managed to change my views a few times (I'm sorry). :roll: :D
  • #1165 19935820
    Janusz_kk
    Level 39  
    Krzychooo wrote:
    Currently, in my opinion, it is better to load 10kWh into the network and receive 8 than nothing.
    I'm wrong?

    If the voltage is too high, you will not load much into the network, the energy from the panels will be lost, if you intelligently control the heaters, you will use the energy without taking it from the network, it may be different on the relays.
  • #1166 19935833
    Krzychooo
    Level 16  
    Janusz_kk wrote:
    when you intelligently control the heaters, you will use the energy without taking it from the network, it may be different on the relays.
    Of course, there is full agreement with that, especially with relays, but are we not beating foam here?
    The topic of the day (not the thread of course) is probably to avoid stopping / resetting the inverter ...?
  • #1167 19935844
    sibartt
    Level 11  
    And such a question on the occasion of tensions and countries. If I do not enter the country code for the first time, what cut-off parameters does the inverter operate on?
  • #1168 19935845
    Janusz_kk
    Level 39  
    Krzychooo wrote:
    The topic of the day (not the thread of course) is probably to avoid stopping / resetting the inverter ...?

    So there is an alternative,
    1 we take the energy (heaters) and the inverter goes.
    2. we only take our energy (heaters) and the inverter also goes so much that it gives less.
    In 1, we cannot check whose energy we are taking because the system is primitive, i.e. the voltage relay and heaters, we heat and the inverter goes to full or not because the neighbor also produces a lot and we only have weak heaters and a tank that after 2-3 hours is almost boiled.
    In the second option, the system is more complicated, but we do not have any losses because we do not take external energy and heat the tank as much as the panels give, assuming that without our energy, the voltage in the network is within the normal range.
  • #1169 19935893
    Krzychooo
    Level 16  
    Well, the natural limitation is the energy capacity of the buffer, whatever it is. Here we have the barriers, the boundary and the failure of every theory / algorithm.
    However, as long as we do not go into sophistry, I will insist that (if the buffer allows it) it is always better to heat / accumulate and give work to the (own) equipment,
    even at the cost of a loss of 20/30% than to rest on "0" (or laurels) and nibble nothing of stellar fusion energy.
    But these are another philosophical considerations that I think it's time to close.

    sibartt wrote:
    If I do not enter the country code for the first time, what cut-off parameters does the inverter operate on?
    As far as I remember, my inverter did not want to start without entering the country code at the start, but it was a long time ago which, combined with sclerosis, may be unreliable ... :D
  • #1170 19935991
    Janusz_kk
    Level 39  
    Krzychooo wrote:
    However, as long as we do not go into sophistry, I will insist that (if the buffer allows it) it is always better to heat / accumulate and give work to the (own) equipment,

    As long as you do not forget to turn it off when the light is gone :) I am writing this in the context of what pse shows
    SOFAR 8kW PV Installation: Opinions, Durability, Failures & Experiences with Inverters
    and it shows on renewable -24MW !!!
Reply | New topic
Report a violation of the law

Topic summary

✨ The discussion centers on experiences with Sofar inverters in approximately 8kW photovoltaic (PV) installations, focusing on technical issues, durability, and configuration challenges. Users report generally stable operation with models like Sofar 6.6KTL-X and 5.5KTL-X over extended periods, though some face connectivity problems, especially with Wi-Fi and software availability. A recurring technical problem involves input voltage exceeding the maximum allowed 600V DC for single-phase Sofar inverters (notably the 4KTLM-G2), causing errors such as PVOVP and BusOPV and inverter shutdowns. This is often due to too many PV panels connected in series on a single string, with 15 Q.CELLS Q.PEAK G4.1 305W panels sometimes exceeding voltage limits, especially in cold conditions where voltage rises. Solutions include splitting panels into two strings (e.g., 8 and 7 panels) connected to separate MPPT inputs, though some users report this does not fully resolve the issue. The maximum recommended panels per MPPT input is around 9 to avoid surpassing power and voltage limits. Users also discuss the need for three-phase inverters for larger installations above 7kW on a single phase due to grid operator restrictions. Software and firmware updates are sought after but not easily accessible, with some users lacking Polish language support. Comparisons with other brands like SMA and Fronius highlight Sofar's cost advantage but raise concerns about long-term reliability and service support, which is still developing in some regions. Network-related errors such as Grid OFP (over-frequency) have been reported, with troubleshooting involving network frequency checks and inverter restarts. Overall, Sofar inverters are considered a cost-effective option with some technical caveats related to system design, installation quality, and support infrastructure.
Generated by the language model.

FAQ

TL;DR: Field owners report 0–20 % daily energy loss when Sofar inverters trip on 253 V grid peaks; “set Country Code 12 for Poland and the problem goes away” [Elektroda, 3301, post #18624621] Why it matters: one menu setting often fixes most unexpected shutdowns without replacing hardware.

Quick Facts

• Max. DC input voltage 1000 V & MPPT window 240-850 V (Sofar 8.8KTL-X manual [Uri, #18921613]) • Recommended DC/AC oversize ratio ≤ 1.2 : 1 for KTL-X models [Elektroda, BikeBarian, post #18360391] • Country Code list: PL = 12, DE = 07, NL = 05 [Elektroda, Defence & 3301, post #18851696] • Typical firmware: V2.30 (increases AC limit from 4.0 kW to 4.4 kW on 4.4KTL-X) [Elektroda, prose, post #19034268] • Service e-mail: service.pl@sofarsolar.com; hotline +48 22 123 98 58 [Elektroda, AT PRO, post #18772451]

How reliable are Sofar inverters in everyday use?

Most 6–9 kW owners report trouble-free work for 1–3 years [Elektroda, iborkim, #18112697; Elekt...

Which menu code should I select for Polish grid parameters?

Use Country Code 12 (PL). It lifts the over-voltage trip to 253 V/10 min and 264 V/1 s, matching Polish NC-RFG limits [Elektroda, 3301, post #18851696] Selecting 07 (DE) raises the limit to 264 V but violates declaration of conformity.

My inverter shows ID01 ‘GridOFP’ and stops at noon—what now?

Measure L-N voltage; if it rises above 253 V, ask the DSO to lower tap settings or move PV to another phase. Until then, temporarily change Country Code to DE (07) or install a 230 → 220 V autotransformer [Elektroda, MariuszFEG, post #18623709]

What causes PvOVP / BusOPV errors on 4KTLM-G2 units?

Voc exceeds 600 V in cold sun. Split the 15-panel string into two of 8 + 7 or use a 3-phase inverter that accepts 1000 V DC [Elektroda, noja102, post #18323557]

Is the MPPT Scan function worth enabling?

Enable only when partial shading occurs; it rescans the IV curve at user-set intervals. Service says it "improves harvest under shade" but reduces output 1–2 % on clean arrays [Elektroda, 3301, post #18622124]

How do I update Sofar firmware myself?

  1. Copy the /firmware folder to the SD card.
  2. Insert card, choose Menu → 5.Software Update, enter password 0715.
  3. Wait until ‘Update DSP1 OK’, ‘DSP2 OK’, ‘FUSE OK’, then reboot [Elektroda, Grucha383, post #19029218]

The display boots for one second at dawn—is that harmful?

No. The capacitors charge when DC rises above 180 V, then discharge if current is < 20 mA; this soft-start repeats without affecting lifespan [Elektroda, rydzyk673, post #19035241]

Why does Solarman show 0.9 A per phase even at 0 W?

Firmware ≤ V2.30 reports reactive standby current as active. Real clamp-meter reading is ~0.2 A; ignore the dash-board figure until a patch arrives [Elektroda, wilk125, post #19038447]

Edge case: can the inverter fail after a breaker trip?

Yes—one 8.8KTL-X died after a 16 A AC breaker opened; display stayed dark despite correct DC voltage, requiring warranty swap [Elektroda, gotycki1, post #18771167]

How to auto-run a 1.5 kW boiler only on surplus PV?

Install a PR-energised relay with the inverter’s CT loop; set closure above 4.5 kW export so the heater engages only in excess production [Elektroda, 3301, post #19053070]
Generated by the language model.
ADVERTISEMENT