Right, BMS comms betweend Deye and Pylontech is not optimal. Is anybody using voltages settings instead and have good results?

5 hours ago, maxmaia said:

Right, BMS comms betweend Deye and Pylontech is not optimal. Is anybody using voltages settings instead and have good results?

Yes 

I have fong kong inverters that doesn't support coms between the inverter and the pylontechs.

Two and half years in and zero issues.Touch wood.

It was a self install.

Monitoring is done via a laptop and Multisibcontrol.

I initially ran them at 53,2v and then later changed it to 52,5v max after some recommendations from the forum.

One thing that I noticed on a system which does not have comms and uses voltage as control, when using a voltage of 52.5V, just before reaching end of charge at 52.5V, some cells goes to 3.65 and some are still at 3.45. Some would say that they are not balanced, but after a while all cells are nearly at the same voltage (within 10mV). So the balancer does work and I suspect the difference in voltages (before end of charge) could be aging of some cells. What I still need to investigate is if it would do the same if there is comms or would the inverter lower the charging low enough to prevent the cell voltage going so high. 

1 hour ago, JacquesVDM said:

One thing that I noticed on a system which does not have comms and uses voltage as control, when using a voltage of 52.5V, just before reaching end of charge at 52.5V, some cells goes to 3.65 and some are still at 3.45. Some would say that they are not balanced, but after a while all cells are nearly at the same voltage (within 10mV). So the balancer does work and I suspect the difference in voltages (before end of charge) could be aging of some cells. What I still need to investigate is if it would do the same if there is comms or would the inverter lower the charging low enough to prevent the cell voltage going so high. 

Yes that is not unusual for the cells to overshoot somehow. The major advantage of BMS comms is the Pylon will instruct the inverter to throttle down to as low as 10A during the tail end of the charge in order to kerb the overshoot. So if one is only in voltage mode its a good thing to set the charge voltage lower to combat this issue and also to set the max charge current conservatively low at say 20/25 amps. The result is usually that the pack will not reach 100SOC, but thats ok. One can from time to time increase the charge voltage to a higher value and limit charge current to 10A in order to reach close to 100SOC.

7 minutes ago, BritishRacingGreen said:

Yes that is not unusual for the cells to overshoot somehow. The major advantage of BMS comms is the Pylon will instruct the inverter to throttle down to as low as 10A during the tail end of the charge in order to kerb the overshoot. So if one is only in voltage mode its a good thing to set the charge voltage lower to combat this issue and also to set the max charge current conservatively low at say 20/25 amps. The result is usually that the pack will not reach 100SOC, but thats ok. One can from time to time increase the charge voltage to a higher value and limit charge current to 10A in order to reach close to 100SOC.

A thought that has come to mind, is if one is unfortunate to not have bms control but fortunate enough to have HomeAssistant, then one can script the latter to throttle charge current when the battery voltage reaches a certain threshold. This then becomes  a poor mans bms control!  Of course the actual bms has metrics for individual cells while the HA script can only see the total voltage, but its still good enough, just select the 10A at an lower thtrshold voltage than the Pylon would have. The result is you will not be able to charge the pack in the fastest time possible, but thats  small price to pay. 

 

That's an interesting idea using throttling charge control via Home Assistant. Then is has to be checked when batteries are back under eg. 92% to set it to initial charging amperage value. 

18 minutes ago, maxmaia said:

That's an interesting idea using throttling charge control via Home Assistant. Then is has to be checked when batteries are back under eg. 92% to set it to initial charging amperage value. 

Yes, if you have access to SOC metric in HA, you can leverage this well to affect even better control, along with the pack voltage. 

Care needs be exercise though that one must limit HA to change settings of the inverter  to  not exceed  30 changes per day. You might exceed the wear limit of the EEPROM nonvolatile storage  in say 10 years time given a 100000 write cycles of EEPROM. @Coulomb might be able shed some light here on wether modern EEPROM / FLASH  still has tight constraints. 

Edited June 10, 20242 yr by BritishRacingGreen

18 hours ago, BritishRacingGreen said:

You might exceed the wear limit of the EEPROM nonvolatile storage  in say 10 years time given a 100000 write cycles of EEPROM. @Coulomb might be able shed some light here on wether modern EEPROM / FLASH  still has tight constraints. 

From the PIP-4048MS etc index:

[url=https://forums.aeva.asn.au/viewtopic.php?p=63091#p63091]Eeprom wear and saving parameters[/url] 

Basically, the Eeproms are rated for a million cycles, so that should not be a problem. Whether that rating is realistic or not, I have no idea. There are a number of glitches that can be attributed to Eeproms, but I suspect that they are firmware race condition issues. I doubt that frequent writing to eeprom would noticeably increase the chances of such a glitch. 

Caught mine doing the same now on pack 2

3.604v (spotted it as high as 3.65)

Sunsynk + 2x UP5000

Got no reason to believe my BMS comms between inverter and battery is wrong.

 

 

Edited June 13, 20242 yr by Acheron

On @BritishRacingGreen suggestion, I setup now a automation in HA to reduce charging speed to 10A when one of batteries reaches 92%. It works fine, still noticed a 3.56V for one cell, but again, very brief, under a second. Now lowered the charging threshold to 5A and will monitor how it is, it should be good, we'll see...

1 hour ago, maxmaia said:

On @BritishRacingGreen suggestion, I setup now a automation in HA to reduce charging speed to 10A when one of batteries reaches 92%. It works fine, still noticed a 3.56V for one cell, but again, very brief, under a second. Now lowered the charging threshold to 5A and will monitor how it is, it should be good, we'll see...

The 92 % might be way too hi,. Its good to note you have implemented this control system and look forward to what you  will discover and test. 

 

Edited June 13, 20242 yr by BritishRacingGreen

Did some more digging for what I saw above:

Comms clearly established from inverter to batteries indicated a charge of 53.2V


Checking Solar Assistant (connected directly to batteries via separate comms cable) indicates recommended is 53.3V

So is the inverter at fault here for pushing this higher than it should OR should the BMS stop this from happening anyway? Somewhere somehow there is a breakdown in comms and the installer/myself cannot be blamed here is a its all controlled automatically via BMS to inverter comms. Nowhere I have set a charge voltage to be followed.

Edited June 13, 20242 yr by Acheron

On 2024/06/13 at 3:27 PM, Acheron said:

Did some more digging for what I saw above:

Comms clearly established from inverter to batteries indicated a charge of 53.2V


Checking Solar Assistant (connected directly to batteries via separate comms cable) indicates recommended is 53.3V

So is the inverter at fault here for pushing this higher than it should OR should the BMS stop this from happening anyway? Somewhere somehow there is a breakdown in comms and the installer/myself cannot be blamed here is a its all controlled automatically via BMS to inverter comms. Nowhere I have set a charge voltage to be followed.

It seems very common that some inverters are just not good at controlling voltage. Victron actually set their max voltage at 52.5v despite what the battery BMS is telling it.

I so similar with mine on one set of batteries (trialing)  by altering the CAN messages. On my other 2 sets I don't  and have never had any over voltage. (All 3 sets have the same Sofar inverters).

EDIT: Ignore

Edited June 18, 20242 yr by Acheron

Any clue maybe how to set maximum SOC to 98% on Deye? I believe the only posibility will be also via HA when it reaches 98% to set charging current to 0 or so....

HI GUYS - AFTER MY ORDEAL WITH THE OVERCHARGED PYLONTECH BATTERY - GOT NEW PYLONTECH BATTERIES NOW INSTALLED WITH MY LUXPOWER 5KW - BY APPROVED AND RELIABLE INSTALLER - ALL RUNNING VERY GOOD - JUST FOR INTEREST WANT TO KNOW - WE GOT SYSTEM SETTINGS :

CHARGE SETTINGS - BATTERY SOC - 70% START - END CHARGE - 95%

CAN WE CHANGE THE 70% START CHARGE LOWER TO SAVE ESKOM POWER CHARGING OR WILL THAT NOT HELP AT ALL.

HEARING FROM YOU EXPERTS PLEASE AND THANK YOU 

Looking for some one close to Centurion that can repair my UP5000. It needs BMS and the say one cell is at 0v. The battery alarm was overcharge. It’s 840 days old. 

HENNIE - EK DINK JY HET N PROBLEEM - HIERDIE OUENS IN S.A. SUKKEL OM HIERDIE GOED REG TE MAAK - EN PYLONTECH COVER NIE OVERCHARGED BATTERYE NIE - EK IS DEUR DIE HELE PROSES - MET ALMAL GEKONTAK EN ALMAL DRAAI NET WEG EN VOEL GEENSINS OF HULLE WIL HELP NIE. MOES OP OU EINDE NUWE EEN KOOP UIT MY SAK SONDER WAARBORG - MYNE WAS MAAR 8 MAANDE OUD.

HET NUWE SUPPLIER / INSTALLER GEKRY WAT MY SISTEEM DIENS EN EK DINK HY SAL NOGAL KAN HELP MET IETS.

 

KONTAK HOM - 

ALEX BORYNA - VAN " HUSARIA SOLAR"

HULLE IS ONGELUKKIG IN ROODEPOORT - MAAR DINK TOG HY SAL KAN HELP - 

072 772 8594

Hi All, I need some guidance here. I woke up today to a dead inverter (Synapse 3.0+) and 2 Pylontech UP2500 lithiums. I contacted the original installer but he is currently offline and will hopefully get back to me later. Is this the best approach to contact him as my first port of call. Are there service providers in the industry who one can call for support similar to how one would call in a plumber? My batteries charge off Eskom and this is the first time this has happened. I see that the main inverter switch was left on and that probably had my lights and tv running directly off the inverter and not through Eskom and probably why the battery died? I have now switched off the main inverter switch in the hope that the batteries will charge but I’m not hopeful. I have had these batteries for about 16 months now. Any ideas or advice will be highly appreciated. Thanks

On 2024/08/01 at 3:45 PM, MARTIN VICTOR said:

HI GUYS - AFTER MY ORDEAL WITH THE OVERCHARGED PYLONTECH BATTERY - GOT NEW PYLONTECH BATTERIES NOW INSTALLED WITH MY LUXPOWER 5KW - BY APPROVED AND RELIABLE INSTALLER - ALL RUNNING VERY GOOD - JUST FOR INTEREST WANT TO KNOW - WE GOT SYSTEM SETTINGS :

CHARGE SETTINGS - BATTERY SOC - 70% START - END CHARGE - 95%

CAN WE CHANGE THE 70% START CHARGE LOWER TO SAVE ESKOM POWER CHARGING OR WILL THAT NOT HELP AT ALL.

HEARING FROM YOU EXPERTS PLEASE AND THANK YOU 

did you get a replacement set from them ? what was the outcome on your claim ?