Jump to content

Axpert King 5Kw (4000w PV) - Firm 71.90 (stock)


Martin S
 Share

Recommended Posts

Hi All,

I need help with my Axpert King 5Kw that came with 71.90 firmware. 

My inverter has the 'PYL' battery option but I am not using Pylontech batteries, so I am forced to go with the "USE" option

I am using 2x wall-mount LiFePO4 batteries that each have their own build-in Daly BMS (48v 100AH) 

Everything works great except that the inverter prematurely switches to float charge, so now I have a case where the battery's SoC is at 70% and the inverter tries to charge the remaining 30% with only 4A, bulk normally charges around 20-35A from MPPT.

The batteries, according to the manufacturer supports CAN- communication at 500 kbit/s, I tried the PYL option with a CAN-type-b and CAN-type-A cable but I get a fault 61(communcation error) on the inverter. I think Pylontech uses RS485 for comms?

My goal is to charge my batteries without the premature float, best case scenario is to have comms working between the inverter and battery.

 

You help is much appreciated

https://ibb.co/WF6sNCM
https://ibb.co/2vt0Npy
https://ibb.co/1Xn7dT9
https://ibb.co/tQTccM5

[url=https://ibb.co/WF6sNCM][img]https://i.ibb.co/sQ2tp7N/20210220-120437.jpg[/img][/url]
[url=https://ibb.co/2vt0Npy][img]https://i.ibb.co/D9CPpjt/20210220-115457.jpg[/img][/url]
[url=https://ibb.co/1Xn7dT9][img]https://i.ibb.co/2M6Wsdj/20210220-115534.jpg[/img][/url]
[url=https://ibb.co/tQTccM5][img]https://i.ibb.co/rFRMMGJ/20210220-115510.jpg[/img][/url]

Edited by Martin S
fix typo's
Link to comment
Share on other sites

13 hours ago, Martin S said:

I need help with my Axpert King 5Kw that came with 71.90 firmware. 

My inverter has the 'PYL' battery option but I am not using Pylontech batteries, so I am forced to go with the "USE" option

Actually, you could update the removable display firmware (the one that talks to the BMS), and have the choice of 6 other BMS protocols other than PYL. But sadly, none of those look like Daly (but I don't know battery BMSs very well).

13 hours ago, Martin S said:

Everything works great except that the inverter prematurely switches to float charge, so now I have a case where the battery's SoC is at 70% and the inverter tries to charge the remaining 30% with only 4A, bulk normally charges around 20-35A from MPPT.

Yes, that bug comes for free with every inverter-charger out of the Voltronic Power factory. You can work around it with the "bulk charging time" option (actually absorb time), or even the equalisation settings. But these have the chance of spending longer than necessary in absorb (reducing life), or less than necessary (still not fully charging the battery some days). Perhaps best to use one of the workarounds for now, until Weber and I get around to patching the King main firmware.

Or you could temporarily use patched firmware version 71.80d, which is a small step back from the 71.90 that you are using now.

13 hours ago, Martin S said:

The batteries, according to the manufacturer supports CAN- communication at 500 kbit/s, I tried the PYL option with a CAN-type-b and CAN-type-A cable but I get a fault 61 (communication error) on the inverter. I think Pylontech uses RS485 for comms?

My understanding is that Pylontech can use either RS-485 or CAN, but only the most advanced removable display firmwares support CAN, and Pylontech is only supported by the removable display firmware via RS-485.

13 hours ago, Martin S said:

https://ibb.co/WF6sNCM
https://ibb.co/2vt0Npy
https://ibb.co/1Xn7dT9
https://ibb.co/tQTccM5

[url=https://ibb.co/WF6sNCM][img]https://i.ibb.co/sQ2tp7N/20210220-120437.jpg[/img][/url]
[url=https://ibb.co/2vt0Npy][img]https://i.ibb.co/D9CPpjt/20210220-115457.jpg[/img][/url]
[url=https://ibb.co/1Xn7dT9][img]https://i.ibb.co/2M6Wsdj/20210220-115534.jpg[/img][/url]
[url=https://ibb.co/tQTccM5][img]https://i.ibb.co/rFRMMGJ/20210220-115510.jpg[/img][/url]

I don't know why the img tags don't work on your images. But if you paste the bare URL (https... .jpg), press enter, and second or two, it displays the image:

20210220-120437.jpg

 

20210220-115457.jpg


20210220-115534.jpg


20210220-115510.jpg

 

Link to comment
Share on other sites

I have taken your suggestion regarding the bulk charge time and set that to 900 minutes, I have dropped the the bulk charge voltage to be the same as the flaot charge (54v). So now atleast the battery will get a constant current and voltage.
Inside the battery there is a BMS which manages 15x 3.2V cells, the reason I decided to go with the bulk time hack is because the BMS inside the battery will actually stop charging the cell once ideal volts and current is reached.

 

Thanks for your detailed reply @Coulomb.

 

Link to comment
Share on other sites

2 hours ago, Martin S said:

your suggestion regarding the bulk charge time and set that to 900 minutes, I have dropped the the bulk charge voltage to be the same as the float charge (54v).

If you choose to have the bulk/absorb and float voltages the same, then the premature float bug is largely irrelevant, and there isn't any (much) need to set the "bulk" charge time. I say "much" because it's preferable to stay in bulk/absorb stage as long as possible, in that when in float mode, there is the danger that the inverter-charger will decide to change back to bulk stage, and that goes via zero and very low charging for about a minute. That can be unnecessarily hard on the battery if you happen to have a large load on at the time (which is likely, because large loads tend to trigger the change back to bulk stage).

2 hours ago, Martin S said:

the BMS inside the battery will actually stop charging the cell once ideal volts and current is reached.

The way the BMS stops charging is to disconnect the battery from the charge source, i.e. from the inverter, via a massive MOSFET switch inside the battery. They're supposed to be able to switch off charging without switching off discharging, but I'm dubious about that. The inverter can act quite strangely when the battery suddenly disconnects, so it's best to avoid this if at all possible.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...