PIP-5048MK inverter

[saviothecnic]

Hello,
a couple of days ago an Axpert King inverter I have on a system had a catastrophic failure, and went in bypass with a fault number indicated.
See the attached images. Also telemetry data graphs are included.

Credevo d'essere unico Italiano con il KING serie UNO
Mi spiace per quello che ti è accaduto ma hai provato da altri venditori Italiani magari a pagamento te lo riparano anche se non venduto da loro

Adirittura insetti dentro inverter che insetti erano mo mi stai facendo preocupare anche per i miei King che sono montati all' aperto

I thought I was the only Italian with the KING series UNO
I'm sorry for what happened to you but have you tried from other Italian sellers maybe for a fee they will repair it even if not sold by them

Even bugs inside the inverter what bugs were mo you're making me worry about my King too which are mounted outdoors

[matteog]

Credevo d'essere unico Italiano con il KING serie UNO

Ne ho ben tre su due impianti diversi, uno singolo e due in parallelo

The issue is, Italian resellers do not want to have anything to do with warranty claims.
I'm pretty sure they just bought a bunch from Alibaba, added 50% to the price and called it a day...

I'll try to contact MPPsolar and ask if they recognise the serial number as one of theirs and offer some help...

[matteog]

Well, TX1 is out!






I could have done a better job without cooking the board (yes, those burn marks on the board were not from the failure...), but there's nothing important in that area, and the heatsinks on the MOSFETs really did suck a lot of heat from the 600°C air gun.
The NTC1 sensor that is on the PCB directly under the transformer is still doing fine, also is its plastic standoff.

TX1 is currently enjoying a bath in Nitro, I'll update you as soon as the resing dissolves and I can reverse-engineer the windings.
Should be simple though, as it's a regular 4 wire, 2 coils transformer.

[reapster]

Hey @matteog ! How did your transformer replacement go? I've been checking back often to see what the outcome was

Hope it went/is going well!

[jumajazu]

Did you find out what was the cause?

I also have this relay clicking issue. For me I know the cause, it happens when the inverter loses connection to the BMS and the back to grid gets lost somehow.
My Back to grid (which becomes 52.0 I think) is then above the back to discharge voltage (51.0). I think the inverter then consistently switches a relay on and off trying to go back to grid and back to discharge.
If I manually adjust the back to grid voltage to 48.0V the clicking stops and things continue like normal again for a while.

My sound is not a relay clicking for sure. It sounds more like soft static discharge or sparking. I have not found out the cause, but have come across a few more owners reporting the same sound, some suggesting it has something to do with magnetic forces in transformers/coils (one of them opened the inverter and confirmed the sound was coming from transformers). My inverter has been in use for 8 months and working normally and the clicking sound has always been there without change. I always feel uneasy when I hear it, but the system has been working fine for quite some time, so I hope it is just some poor design of the magnetic parts without impact on performance.

[weber]

@jumajazu, that sounds like, and @matteog's photos look like, insulation failure in the high voltage winding of the transformer. Corona discharge, followed by arcing, possibly involving the core as part of the conducting path. Maybe they are skimping on insulating film or tape between the winding and the core, or between layers of the winding.

[jumajazu]

Thanks, weber, for your insights.
Could the inverter possibly work with such an insulation failure for more than 8 months nonstop without any other signs connected with the sparking (voltage fluctuations, smell)? I cannot open the case as it is still under warranty, but one of the members at our local forum, who had the same sound coming from his King, opened the case and confirmed it was coming from two transformers. Several forum members reported the same sound, which would indicate not a random fault, but an improper design. However, none of them reported any trouble with their invertors.

[matteog]

I can only see some increased temperature and current drain from the PV to the 48v bus in the few hours previous to the failure, but didn't really notice anything in the months before.
I also have 2 more Axpert King 5000w in parallel in another system working since 2020 and they are still rocking.
Would it be possible that the low side MOSFETs got stuck open (by the animal-bug that was in the back of the board?), and this caused a prolongated DC current passing into the transformer?
I'm not sure beacuse this failure took a couple of minutes, and the 300v bus was still going strong, so the low side MOSFETs were pulsing correctly I suppose...

[jumajazu]

hello, matteog, as weber thought my sparking sounds and your failure could be due to the transformer's insulation failure, did you notice any sounds like I described in your machine before the failure (similar to sparking or soft static discharge sounds)?

[matteog]

Unfortunately I couldn't tell, that system is in a semi-remote location and up to my visit a couple weeks before, nothing seemed suspicious.

[jumajazu]

And the two other Kings in your other system, no sparking/strange sounds coming from them except for fan noise? Could you possibly check for me when you are near them? The sound I am looking for is recorded by another user here https://youtu.be/tYkCDHX_djs. Thanks

[weber]

Thanks, weber, for your insights.
Could the inverter possibly work with such an insulation failure for more than 8 months nonstop without any other signs connected with the sparking (voltage fluctuations, smell)?

Ah. No. I failed to appreciate that it had been doing it for 8 months. Sorry.

If it involved corona-discharge or arcing, I would expect it to progress to complete failure within a few days.

I cannot open the case as it is still under warranty, but one of the members at our local forum, who had the same sound coming from his King, opened the case and confirmed it was coming from two transformers. Several forum members reported the same sound, which would indicate not a random fault, but an improper design. However, none of them reported any trouble with their invertors.

In that case, I hypothesise that some minor firmware bug is causing a periodic short-duration (maybe nanoseconds) high-current spike and the transformer is acting like a speaker. If this was to lead to a failure, it would more likely be a failure of MOSFETs or IGBTs, not the transformer.

[coulomb]

The ATE1 command

Recent events revealed to me the purpose of the undocumented ATE1 command. It puts removable displays into a mode where the regular cycle of query commands is interrupted, and any characters received from the PC port are echoed (copied) to the DSP port. The effect is that any command that you send to the display effectively bypasses the display and its usual and limited parsing, and sends the command unmodified to the DSP in the inverter. That means that certain commands that are usually blocked by the display can now be sent to the DSP, at the cost of the display no longer updating its status. These commands include the battery calibration "nudge" commands, commands needed to fix fault code 90 (these commands have to be tailored to a particular serial number by Voltronic via your reseller), commands like QOLBY and POLBY (King specific), and many others.

This "echo everything" mode can be exited by the command ATE0, although some models seem to need a restart (cycle the power).

I believe that this command should work with any Axpert model that has a removable display, or the newer colour non-removable display with the round LED ring. Models with the non-removable monochrome display do not need this command.

Older readers may recall back in the days of dial-up internet sending commands to their modem using the "AT command set". There were commands to get the ATtention of the modem, and be interpreted as commands. There were many such commands, but a common one used at the beginning of a session was ATE1 to enable local echo, so you could see what you were typing if the other end wasn't echoing them. ATE0 was indeed the command to exit this mode. Presumably, this is the origin of these commands' names.

By a happy coincidence, or perhaps by design, the checksums for ATE1 and ATE0 are both printable. They are respectively Nm and ^L (two characters, up arrow and capital L). So it's possible to nudge the battery calibration using only a simple serial communications program. Though you could also use the Voltronic communications tool (or download from MPPSolar's downloads page), which calculates CRCs automatically.

[ 14/11/2024: Added note that ATE0 may not work. ]

[saviothecnic]

@coulomb

Question for KING inverter version one
Have you also modified the firmware with the compensation factor K by modifying the latest release versions for this inverter and for the premature float problem?

[coulomb]

Have you also modified the firmware with the compensation factor K by modifying the latest release versions for this inverter and for the premature float problem?

Yes, Weber and I have been working on this every Friday since April. It's almost ready, we basically just need to do a few measurements and remove a few question marks from the documentation.

If you're keen, I could send you a pre-release version.

[saviothecnic]

[ Edit Coulomb: Sigh. I edited instead of quoted again. Hopefully all the original post is still there. ]

but first let's understand if you are working on the version
compatible with me my current FW are :
U1 72 00

Yes, we're working on patched firmware version 72.00b, based on that version.

U2 02 83

We're working on patched firmware version 02.81b, based on factory firmware version 02.81. We did come across 02.83 after we had done a lot of work on 02.81, but I decided that 02.83 was very little different from 02.81. I just checked again, and now I'm only 95% certain that I'm right. So give me a little more time to figure this out.

U3 00 24
U4 1 10

These should be OK.

I have two KING UNO mounted in parallel to each other

One problem is that we only have the one King, so we can't test paralleling. Some of the changes involve changing CAN packet contents, which only affects paralleled machines. Weber did consider purchasing a second King so that we could test paralleling, but it wasn't obvious how to buy one now that MPP Solar Australia no longer seem to carry them. So that's stalled for now.

1 calibration in the reading of the KING voltages
2 I think this calibration is even more relevant due to the lack of the K factor during charging and discharging

By K factor I assume that you are referring to Load and Charge battery voltage compensation.

We have made it easier to calibrate the voltage readings, adding a new setting for this purpose.

3 I have the problem that when the battery is fully charged
it starts to draw from the battery and I don't understand this
Maybe it's part of the premature float bug

It's normal for Axperts, including Kings, to stop charging altogether at the end of the absorb stage, for a minute or so. Then, depending on load, it may take a while for the battery voltage to fall to the float voltage. At that point, the solar charger should start up and support the loads, topping up the battery if necessary to get it to reach the float voltage setting. With the premature float bug, when solar charging it will stop charging when the charge current is low enough and the battery voltage is withing half a volt of the float setting (should be the bulk/absorb/CV setting). Whether you see this or not depends on whether there is a cloud that reduces charging current low enough for long enough.

4 the most important thing I would like if you succeed
to add it on the modified firmware and a current limit
on the discharge that can send the inverter to Bypass UTI

Added features will have to wait I'm afraid. Weber and I have spent ridiculous amounts of time on this already, and other tasks are piling up. This feature sounds like a lot of work, and may or may not end up being practical. Meantime, if you properly set up KettleKomp™ (Load/Charge battery voltage compensation), this may reduce your problem.

[coulomb]

We did come across 02.83 after we had done a lot of work on 02.81, but I decided that 02.83 was very little different from 02.81. I just checked again, and now I'm only 95% certain that I'm right.

Weber and I have just decided that it's simpler and less confusing to switch to patching 02.83a rather than continue with 02.81a. So that solves that problem.

Yet, as ever, it's more work that I thought. Despite our latest "patching technology". Sigh.

[saviothecnic]

And the two other Kings in your other system, no sparking/strange sounds coming from them except for fan noise? Could you possibly check for me when you are near them? The sound I am looking for is recorded by another user here https://youtu.be/tYkCDHX_djs. Thanks

From the video it seems that the battery is missing
The KING cannot work without a battery
for this it goes into error perhaps there is a PV input that holds
DC side inverter alive I know that the user of the video is Italian like me too bad he didn't enable comments but isn't yours the exact video?

[saviothecnic]

Weber and I have just decided that it's simpler and less confusing to switch to patching 02.83a rather than continue with 02.81a. So that solves that problem.
Yet, as ever, it's more work that I thought. Despite our latest "patching technology". Sigh.

Ok I'm happy for this
Since soon I will get a Seplos BMS and therefore have
a patch based on the latest version of the official FW
It gives me confidence that it also supports protocols simulated by the Seplos BMS
I attach an image of the inside of the LCD of my inverter
If you know where I can buy a spare like this I would be safer
to use a firmware and be able to go back in case
of problems or blockages.

LCD KING UNO

LCD_King1Interno.jpg (174.91 KiB) Viewed 13831 times

[saviothecnic]

I have two KING UNO mounted in parallel to each other

One problem is that we only have the one King, so we can't test paralleling. Some of the changes involve changing CAN packet contents, which only affects paralleled machines. Weber did consider purchasing a second King so that we could test paralleling, but it wasn't obvious how to buy one now that MPP Solar Australia no longer seem to carry them. So that's stalled for now.

If I can go back and there is no risk of disturbance between the two phases, I can prove important and that he stays alive
parameter 28 for parallel

1 calibration in the reading of the KING voltages
2 I think this calibration is even more relevant due to the lack of the K factor during charging and discharging

By K factor I assume that you are referring to Load and Charge battery voltage compensation.

Yes, that's exactly what I'm referring to Even if I don't quite understand how I have to configure it of precision

We have made it easier to calibrate the voltage readings, adding a new setting for this purpose.

Excellent, perhaps even a youtube video that shows how this K calibration is would be nice

3 I have the problem that when the battery is fully charged
it starts to draw from the battery and I don't understand this
Maybe it's part of the premature float bug

It's normal for Axperts, including Kings, to stop charging altogether at the end of the absorb stage, for a minute or so. Then, depending on load, it may take a while for the battery voltage to fall to the float voltage. At that point, the solar charger should start up and support the loads, topping up the battery if necessary to get it to reach the float voltage setting. With the premature float bug, when solar charging it will stop charging when the charge current is low enough and the battery voltage is withing half a volt of the float setting (should be the bulk/absorb/CV setting). Whether you see this or not depends on whether there is a cloud that reduces charging current low enough for long enough.

So I understand if you corrected this too I should finally have the battery fully it also charges on days with some passing clouds

4 the most important thing I would like if you succeed
to add it on the modified firmware and a current limit
on the discharge that can send the inverter to Bypass UTI

Added features will have to wait I'm afraid. Weber and I have spent ridiculous amounts of time on this already, and other tasks are piling up. This feature sounds like a lot of work, and may or may not end up being practical. Meantime, if you properly set up KettleKomp™ (Load/Charge battery voltage compensation), this may reduce your problem.

Yes, I certainly believe that the current Patches should already help me

I'm not a programmer but I know that the discharge A limit is present in the MAX series in parameter 41

Inverter that I had for two days and then returned by choosing the KING UNO for its useful On-Line function which stabilizes
the output voltage even when it is in USB mode
Now I don't know whether to see the MAX firmware at parameter 41
it is useful to add it also to the KING UNO firmware

[coulomb]

I'm not a programmer but I know that the discharge A limit is present in the MAX series in parameter 41. ... It is useful to add it also to the KING UNO firmware

For the time being, and probably forever, firmware transplants like this are off the menu. It's just too much work without source code, and probably quite a lot of work even source code was available. Sorry.

[coulomb]

Beta Version of Patched Firmware 72.00a / 02.83a for PIP-5048MK/Axpert King 5K

Firstly, a huge thanks to Power Forum user Youda, who generously paid for Weber and I to buy an Axpert King to work on.

This is the first fully patched firmware for PIP-5048MK / Axpert King (not King II). The patches are based on main firmware version 72.00 and removable display firmware version 02.83.

The main version should display as "BCa72.00" (non-LFP) or "BFa72.00" (LFP) on Watchpower, and possibly on other monitoring software that displays the full version number as a string.

Here is the new setting ("setting number -1") for nudging the battery voltage calibration:

72.00a battery voltage calibration setting.jpg (33.44 KiB) Viewed 13740 times

Here is a partial list of new features, compared with factory firmware:

• The premature float bugs are fixed, as in all our patched (main) firmwares.
• AussieView™, where you get to select data to display on the middle and bottom rows independently. NOTE: This takes a little getting used to; press the enter key (⏎) to select which row the up and down keys affect. More data can be displayed, e.g. temperatures, and the "seven segment font" is improved.
• KettleKomp™ minimises panic by the firmware when the battery voltage dips on heavy loads or rises on heavy charging.
• Dynamic Charge Control is only partly functional. It is intended to allow using serial commands to change the total battery charge current limit in one amp steps and without restarting the solar charger or wearing the EEPROM. But South African Power Forum user Calvin has reported that it does not work with solar charging. It only works with AC charging. The SCC continues to use the EEPROM value of maximum charge current. [Edit by Dave Keenan, 9-Nov-2024]
• Dynamic Load Control allows using serial commands to put one or more paralleled inverters into standby mode so they consume less power when not needed.
• There is the new setting (numbered -1) for simplified battery voltage calibration. This avoids having to send any serial commands. You can nudge the reading up or down, and save the calibration.

There are over 100 patches split approximately evenly between the main (U1, DSP) and display (U2, MCU) firmwares. These firmwares should always be used together. If running on paralleled machines, always use the same firmware pairs on all machines. Be aware that we only have one King here for testing, so we can't be sure that there aren't bugs that affect paralleled and/or 3-phase machines. But South African Power Forum user Calvin reports that all features other than Dynamic Current Control work as advertised in his 3-parallel-machines setup. [Edit by Dave Keenan, 9-Nov-2024]

Warning!
Flashing this firmware to an incompatible machine will likely brick the inverter!

For some combinations of firmware, the reflash tool will not prevent this.

Often, there is no reversing this situation. You have been warned!



Main (DSP) patched firmware for lithium ferrous phosphate (LFP) (16S or 15S), including Pylontech:

dsp_BF1_72.00a.zip

(1.25 MiB) Downloaded 470 times

Here's a description of the differences between the LFP and non-LFP flavours.

Main (DSP) patched firmware for lead acid (24S), lithium cobalt-blends (LCO, NMC, NCM, NCA) (14S), and lithium titanate (LTO) (21S or 20S):

dsp_BC1_72.00a.zip

(1.25 MiB) Downloaded 296 times

Removable display (MCU) patched firmware, all battery types:

mcu_BU2_02.83a.zip

(1.38 MiB) Downloaded 547 times

See these Firmware Upload Instructions for Models with a Removable Display.

It should go without saying that you use this patched firmware at your own risk. Please report any problems to this topic.

[CorLotte]

Here is a partial list of new features, compared with factory firmware:

• The premature float bugs are fixed, as in all our patched (main) firmwares.
• AussieView™, where you get to select data to display on the middle and bottom rows independently. NOTE: This takes a little getting used to; press the enter key (⏎) to select which row the up and down keys affect. More data can be displayed, e.g. temperatures, and the "seven segment font" is improved.
• KettleKomp™ minimises panic by the firmware when the battery voltage dips on heavy loads or rises on heavy charging.
• Dynamic Charge Control allows using serial commands to change the total battery charge current limit in one amp steps and without restarting the solar charger or wearing the EEPROM.
• Dynamic Load Control allows using serial commands to put one or more paralleled inverters into standby mode so they consume less power when not needed.
• There is the new setting (numbered -1) for simplified battery voltage calibration. This avoids having to send any serial commands. You can nudge the reading up or down, and save the calibration.

There are over 100 patches split approximately evenly between the main (U1, DSP) and display (U2, MCU) firmwares. These firmwares should always be used together. If running on paralleled machines, always use the same firmware pairs on all machines. Be aware that we only have one King here for testing, so we can't be sure that there aren't bugs that affect paralleled and/or 3-phase machines.

Great job done! Let me ask you. What is the maximum current possible in dynamic charge?

[weber]

Great job done! Let me ask you. What is the maximum current possible in dynamic charge?

Thanks. The maximum is 140 A, same as with the EEPROM setting.

[CorLotte]

Great job done! Let me ask you. What is the maximum current possible in dynamic charge?

Thanks. The maximum is 140 A, same as with the EEPROM setting.

Thanks.