Axpert 5 kVA fault code 06

[Coulomb]

In a profile post by @jussclay:

Quote

Coulomb i hope you well with your vast experience with the Axpert error code 06 overvoltage /abnormal voltage what causes it and how can i reset it 

I've not seen an error 06. It happens when in battery mode the inverter output voltage is 20 V over the nominal voltage for 10 "ticks". A tick is 1/50th of a second, or 20 ms, so it's allowed to go over for 180 ms, but not 200 ms. The nominal voltage is usually 230 VAC, but can be set to 220 V or 240 V with the undocumented POPV command.

This is an actual fault code, not merely a warning, meaning that the inverter is in Fault mode (as opposed to battery or line modes, there are a few others). In fault mode, the inverter doesn't do much, and in my experience usually shuts down completely (even the LCD light goes off and the processor cuts its own power) after a minute or so. So the only way to "reset it" is to start the inverter again. If the fault occurs again as soon as it goes to battery mode, then it has to be repaired.

As to what might cause this, I can only think that the resistor divider chain has failed and it things the voltage is > 250 V when it's really 230 V. If there was a problem with the inverter, like faulty IGBTs, then you'd get no voltage at all. The voltage would be set by changing the PWM, so if it can make any sort of sine wave, it would make one that is 230 V RMS, it seems to me. You might be able to watch the output voltage with a multimeter, but if the output only lasts 200 ms, it might be a challenge. Perhaps use your multimeter's "peak" facility to see what the maximum voltage was.

The good news is that if I'm right and it's just the resistor divider, such a repair should be relatively easy. The voltage divider resistors are usually easy to spot - often four or more of them in series, usually in a straight line with few to no other components nearby. The AC output tracks are easy to spot, since they are pretty thick and striped with solder for good conductivity. The large toroidal inductor is part of the AC output circuit, to give you somewhere to start. You still have to open the case to get the main board out.

The bad news is that if you can't repair it yourself or have a friend do it, it probably doesn't matter how easy the repair is, your supplier will probably replace the main board and throw the old one away, even though the cost of the replacement parts is probably less than one Rand. With labour and workshop fees, that will likely come to nearly the cost of a new unit. Of course, I could easily be wrong about what could cause this fault, so it might cost a technician hours to try and locate the fault. So the repair logic makes sense,

I've attached what one of the service manuals says about fault code 06.

[Coulomb]

3 minutes ago, Coulomb said:

As to what might cause this, I can only think that the resistor divider chain has failed and it things the voltage is > 250 V when it's really 230 V.

Actually, the inverter checks its output with the same sense resistors that it uses to figure out how much PWM to give the IGBTs. So that doesn't sound likely after all. It has to be some sort of control issue, which is handled by the firmware. I suppose if the bypass relay is stuck on, it would read utility voltage, which could be over 250 VAC some of the time. So as the service manual suggests, try running with no utility and no load. If no problem for a while, turn on loads; if no problem for another while, turn on the AC input.

Perhaps a particular load might cause the inverter to become unstable; a few such loads have been identified. So if the problem occurs only with the loads on, try turning off all loads and gradually turn them back on to see which one might trigger the issue.

[jussclay]

thank you a span 

[Dejan]

I have axpert MKS 3kva with the same fault 06.

I can not find any parts that  couse this fault.

I check resistor dividers,and they are ok. 

I followed all the lines from the resistor and checked all the parts there and found nothing.

Does anyone have any advice what to check?

[Coulomb]

My only suggestion is to check the relays. I suspect that the 3 kVA models are a little different, but some sort of relay fault could still cause this. For example, if there is a changeover contact set (normally open and normally closed), or pair of changeover contacts, then look for shorted contacts (normally open to corresponding normally closed). 

If you need to replace a relay, try extra hard to get a good quality replacement. 

[Dejan]

I will try

[JardCrocker]

Hi...i am a new user here. As per my knowledge this device appears to be a transformerless design which makes use of MOSFETS - based on my research MOSFET based inverters  tend to have a lifespan of at least 3-5 years, whereas the transformer based inverters tend to have at least 10 years life span.

bittele electronics

[___]

11 minutes ago, JardCrocker said:

transformerless

Pfffft. Marketing speak. :-) This is a pet peeve of mine so do excuse me while I rant a bit...

The only truly transformerless units are high end grid-tied units that use a PV input voltage around 380V or more. Anything that has a battery (except for high voltage batteries like Tesla) needs a boost stage, and the best way to do a boost stage remains a transformer as it also gives you isolation for free.

(The other ways also use inductors, things that look a bit like transformers, are not much more efficient, and sacrifices isolation).

There are however two distinct kinds of transformers used to do boost stages.

There's the old low-frequency iron type. This works by first creating a low voltage 50Hz AC, and then pushing that through a large iron transformer. Usually has terrible regulation too, output voltage scales with the input voltage.

There is also the more modern way, where you use a much higher frequency, usually between 50Khz and 200Khz, and then use a (much smaller) transformer to step it up to around 400VAC (RMS), then rectify that back to 400VDC, and then chop it up a second time into 50Hz AC. The Axpert uses this method.

MOSFETs are just switching transistors with low internal resistance and are used in both kinds of inverters.

The boost stage of an inverter is the most stressed part of it. Two decades ago we used bipolar silicon transistors, it was big, heavy, ran hot, and did 70% efficiency on a good day. And those things lasted forever...

In our modern culture of consumable electronics... indeed... the more modern stuff usually don't last that long. But it has nothing to do with the design (FET vs Bipolar, low or high frequency transformer)... it has just become easier to make a cheap modern inverter :-)

[Henkt]

Hi

Hoping to find some help.

I have a parallel installation - 5kva

I managed to uograde the FW on the one but the other one seems to bave an issue.

After switching it on it almost immediately goes into fault mode but I can't locate the fault code to identify the issue.

The buzzer sounds contiuously as well.

I've disconnected the other unit and there's no load and no AC input.

In the manual there are a couple of error codes associated with the  batteries but the same bank drives the other unit.

Assistance will be much appreciated.

Thanks

 

[Coulomb]

So this behaviour is only after a firmware update?

It sounds like the firmware update didn't succeed. Can you redo the update, or is it not responding to the ReflashTool?

I'm always very nervous paralleling machines, especially when the firmware changes. Hopefully you had the outputs isolated from each other and the loads during the firmware update process. 

[Henkt]

Hi Coulomb

Thanks for the reply.

Yes I did disconnect the units - I managed to get the second one upgraded as well.

SO I ran through the settings I had previously and tried to set it up in parallel mode with no success.

Each unit can run on it's own without issues (still with no load).

The moment I switch on the second one it brings up the fault alarm - after a while it will switch off by itself.

In the log it shows a "Load error".

Both are now on 72.70C

Thanks

[Coulomb]

15 hours ago, Henkt said:

Each unit can run on it's own without issues (still with no load).

But can each inverter power loads by itself? Each inverter should have an isolating breaker for this purpose. 

15 hours ago, Henkt said:

The moment I switch on the second one it brings up the fault alarm - after a while it will switch off by itself.

So you're using the switch at the bottom of the inverter to tell it to go to battery mode? I never use those switches, and just leave them on. 

15 hours ago, Henkt said:

In the log it shows a "Load error".

How are you accessing the log? Is this on ICC? 

[Henkt]

Thanks Coulomb

I have a single breaker between the batteries and the inverters

Will have to make some cbanges.

After fiddling around , both are now up witb no error condition.  At one stage this morning the one inverter showed  error code 58.

I suspect that one the parallel card of one of the inverters might be faulty.

The cables are all wired correctly for parallel but I cant select parallel mode on either.

Thanks for all the inputs so far.

[Coulomb]

22 minutes ago, Henkt said:

I have a single breaker between the batteries and the inverters

That's fine, I mean on the AC outputs. There should be a breaker near the inverters  for the AC inputs too, but that can be shared between the paralleled inverters. 

22 minutes ago, Henkt said:

I suspect that one the parallel card of one of the inverters might be faulty.

I meant to suggest that you check the connections. 

22 minutes ago, Henkt said:

The cables are all wired correctly for parallel but I cant select parallel mode on either.

Remember that with some firmwares, you have to have the main switch off to be able to select parallel mode. I think that's in case you can't separate the outputs. You don't want one inverter in parallel mode paralleled with another one still in single mode. Even for a fraction of a second, unless they all have the AC input connected and have had time to synchronise with it. 

[Johan Conradie]

Hi, looking for Flasware Tool and version 7270c for axpert, please

[Coulomb]

2 hours ago, Johan Conradie said:

Hi, looking for Flasware Tool and version 7270c for axpert, please

Patched firmware version 72.70c has been superseded by patched firmware version 73.00e.

LF1-72.70c comes with a particular model of cloned Axpert, and that model happens to be one that can't be updated with anything. I believe however that you can obtain (or buy) a new control board (plug-in daughter board) that fixes the issue. See also Do I Own a Clone?

The firmware update tool is inside the .zip file.

[maxie]

please can you help me my friend connect a mpp inverter 3kva on grid   wrong on dc power.so now its  keep on beeping  . how can I fix the fault

[Coulomb]

14 hours ago, maxie said:

please can you help me my friend connect a mpp inverter 3kva on grid   wrong on dc power.so now its  keep on beeping  . how can I fix the fault

It sounds like it's been damaged, so you need to get it repaired. If you're not skilled with electronics, then your only option is to find a suitable repairer. I believe that Mecer can repair Axperts, though they might not be as familiar with 3 kVA models as they would be with 5 kVA models.

If you are skilled with electronics are willing to invest some time in the repair yourself, I believe that there are service manuals for the 3 kVA models in the files section of this forum.

I note that fault code 06 has a slightly different meaning for 1K/2K/3K machines as it has for 4K/5K machines; it's "Output voltage is abnormal" as opposed to "Output voltage is too high". So it could well be showing zero volts output. My guess is that the output IGBTs and the associated gate drivers have failed.

[Ash.VF]

Hi All - i have an Axpert 5kVA that was blown by a utility power surge. It was not protected but now is.

Problem is since re-installation, the unit will not allow for PV charging of the batteries. The PV icon does not come on at all and charging is only possible via utility or generator. I asked the tech that did the repairs and he says the AC and DC circuits are totally separate so the surge would not have damaged that part of the inverter. If this is true then why was there no problem before and now PV's are not working?

Could it be an installation issue, i.e. the PV cables incorrectly connected to the unit or damage to the unit?

Many thanks for any words of wisdom.

[Coulomb]

12 hours ago, Ash.VF said:

I asked the tech that did the repairs and he says the AC and DC circuits are totally separate so the surge would not have damaged that part of the inverter.

Mmm. There is a point of commonality: the battery. If the surge caused a momentary very high battery voltage, or the MOSFETs shorted the battery while the solar charge controller was running, it's vaguely possible.

12 hours ago, Ash.VF said:

Could it be an installation issue, i.e. the PV cables incorrectly connected to the unit or damage to the unit?

That sounds far more likely. If you have a multimeter, you could check for between 60 and 130 VDC at the PV input terminals (take off the cable cover to access these), and make sure that positive and negative are round the right way. If you read zero or negative volts, then that's your problem right there.

The other possibility: Axperts are notorious for having SCC issues after a repair. There are a pair of 4-pin JST cables that can be forgotten or swapped. Without that cable connected correctly, the SCC can power up (I think you would still hear the distinctive ping of the relays connecting), but the DSP won't be aware of the SCC's existence, so the solar panel icon won't come up, and no solar charging will occur.

 

Edited March 12, 2020 by Coulomb
Minor rewording

[Johan van der Merwe]

Good day all,

We had a electrical storm last night and the Axpert 5kw inverter was knocked out. It gives a code 6 error. Reading on the forum it looks like a repair job. Anyone that could suggest a good tecnician. This is in South Africa, preferably North West province.

 

[Johan van der Merwe]

Hopefully it can be repaired, I was smelling burned electrical components on the machine 

[Leo]

Hi there - I have a similar problem with an Axpert 3kVa inverter: Inverter works fine on battery mode or line mode but, as soon as the solar panels are switched in, the unit shuts down showing fault code 06. It only does this in bright light. Why on earth would it do this? 

[Coulomb]

2 hours ago, Leo said:

It only does this in bright light. Why on earth would it do this?

You didn't say what model of 3 kVA Axpert you have. I'm guessing that you have a model with a 450 V max SCC, which means the PV input is bucked down to bus voltage. With the legendary overshoots of Axperts, and the lack of a battery to absorb the overshoots, the bus voltage may be overshooting, and the inverter section may not be able to reign in the AC output voltage in time.

But that's pure guesswork.

Do you have a lot of PV nominal power relative to the rated power of the solar charger? If it's more than 120%, that could be the problem. Perhaps you could try bypassing or isolating one or two panels as an experiment, to see if that prevents the problem. That would also explain why it only happens in bright sunlight.

If you have to lose one or two panels, you could perhaps use an external MPPT to connect those one or two directly to the battery.

[Jaco Engelbrecht]

I have 3 x 5Kw Axpert in Serie ( 15kw) it ran without problem but shutdown yesterday. It switches on few seconds with fault light but switches of after that. Batteries 53.2V charged.