___ Posted November 18, 2019 Share Posted November 18, 2019 2 hours ago, Ironman said: Mine was set to Multiplus - and somehow the multiplus has a completely different SOC level. The Multi does its own measurement of charge going into and out of the battery. In VE.Configure you will see there is also a charge efficiency figure that you can set for your batteries (and the default 0.85 is a bit too pessimistic, even lead-acid users should move it up to 0.88 or 0.9, and LFP should move it to 0.95 even). Now the Multi only knows about its own charge current, it does not (normally) know what the solar chargers are doing. Except that in an ESS system we TELL the Multi what the solar chargers are doing (we periodically take the current reading from the solar chargers and tell the Multi how much extra current is being charged with externally). This means that the Multi CAN do SOC determination on its own. BUT... and this is where a whole lot of caveats come in: You must properly configure the charge efficiency in VE.Configure, an even then, you must remember that the solar-charger-to-Multi-sync is only every 3 seconds. Additionally, the Multi estimates its DC current from the AC values (so it could be off by 1-2A), so this SOC determination essentially does newtonian integration over a value that is affected by a lot of...uhm... factors. So in essence, the SOC determination of the Multi isn't perfect, but to be fair, SOC determination is never perfect, it is always an estimate. It's just that in DC-tied systems, the Multi is usually less accurate than the battery monitor, and it drifts quite a bit more. That is why the default battery selection (Auto) in the GX device will always favour a battery service (BMV or BMS) over the Multi. Additionally, if you use the battery's SOC figure, the GX device will write that across to the Multi so that the Multi uses the external SOC measurement for decisions (in assistants for example), but if the Multi is itself selected as the SOC monitor, it won't do that because writing from yourself to yourself is obviously not the right thing to do. Ironman 1 Quote Link to comment Share on other sites More sharing options...
Gerlach Posted November 18, 2019 Share Posted November 18, 2019 (edited) Just spoke the guys at Bluenova. There batteries floating charge is 55v and get it fully charge after using it is 56.2v Edited November 18, 2019 by Gerlach Ironman 1 Quote Link to comment Share on other sites More sharing options...
___ Posted November 18, 2019 Share Posted November 18, 2019 (edited) 44 minutes ago, Gerlach said: Just spoke the guys at Bluenova. There batteries floating charge is 55v and get it fully charge after using it is 56.2v Victron SmarthLithiums are the same. You charge them to 14.2V per battery, and then "float" at 13.5V. To be clear though, while it is a good idea to lower the voltage a bit after the battery is fully charged, the terminology still hails from lead-acid days. With a lead acid battery you have bulk, absorb, and float. With a lithium battery you really only have "bulk" and "charged". The Multi still retains the old state names and they display on the GX device, so people get confused because they don't understand why it sometimes says Absorption and sometimes Float. When you have a managed battery (eg the Pylontech), do not worry about what state the Multi thinks it is in. The battery calls the shots anyway. Edited November 18, 2019 by plonkster Ironman 1 Quote Link to comment Share on other sites More sharing options...
Youda Posted November 18, 2019 Share Posted November 18, 2019 Majority of the LFP batteries are built as 16S cells for a 48V pack or 4S for a 12V pack. Therefore 56.2V or 14.2V setting. And this setup works great, since it fits into a range of most solar chargers. For a shame, Pylontech opted for a non-standard 15S architecture of the pack and now we have to deal with it: It's a bit harder to finetune the charger for 15S. By removing that 1 cell from the 16S pack, manufacturer also removed a bit of voltage margin between fullycharged and overcharged states. You can't paralel 15S pack with a standard 16S pack. So, you are locked forever to buy from that same manufacturer. But that's the life ___ and Ironman 1 1 Quote Link to comment Share on other sites More sharing options...
___ Posted November 18, 2019 Share Posted November 18, 2019 24 minutes ago, Youda said: For a shame, Pylontech opted for a non-standard 15S architecture of the pack and now we have to deal with it: The 24V batteries are "standard" 8s. Probably because 7s would have been too low Quote Link to comment Share on other sites More sharing options...
Youda Posted November 18, 2019 Share Posted November 18, 2019 Hmm, why not to fit 7 + 1/2 cell into a 24V LFP pack? There must be a way to do this....hold my beer.... SYC, Ironman and ___ 3 Quote Link to comment Share on other sites More sharing options...
wolfandy Posted March 21, 2020 Share Posted March 21, 2020 Hi all, I would like to bring up this thread again. I had a Victron MPPT installed yesterday and have moved my panels off the Axpert onto the Victron. My installer has configured the Victron for my Pylontechs - but I am not 100% of his settings. So I am hoping for a bit of help from you guys please On the Axpert, I had the following charge settings (which seemed to work quite well for me): Bulk: 52.2V Float: 52.0V My installer has now programmed the following values: Absorption: 52.0V Float: 51.0V Equalization voltage: 0.00V Re-bulk voltage offset: 0.40V Absorption duration: Fixed Absorption time: 1h 0m Tail current: Disabled Equalization current percentage: 0% Automatic equalization: Disabled Equalization stop mode: Fixed time Equalization duration: 2h 0m Temperature compensation: Disabled Low temperature cut-off: 5 deg Celsius In ICC I can see that the Pylon gets charged to 52V and then hovers for a while around that value (I assume that this is Absorption) - with SOC at 97%. Then it drops to just under 51V and stays around that value (I assume that this is Float) - with SOC at 96%. So I guess my questions are: Are the settings above made by my installer generally correct? Or is there anything that I need to change? What would you recommend I'd use for Absorption and Float? 52.2V/52.0V as I previously had it or 52.0V/51.0V as it is now? What are upsides/downsides and risks of each? Thanks in advance for your help Quote Link to comment Share on other sites More sharing options...
SYC Posted March 21, 2020 Share Posted March 21, 2020 6 hours ago, wolfandy said: Are the settings above made by my installer generally correct? Or is there anything that I need to change? Yes they perfectly correct and recommended by victron for Pylontech setup. No change 6 hours ago, wolfandy said: What would you recommend I'd use for Absorption and Float? 52.2V/52.0V as I previously had it or 52.0V/51.0V as it is now? What are upsides/downsides and risks of each? No change. As installer set.Check this https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom?_ga=2.146844279.1545381250.1584818150-1826497651.1580643129 read disqus all the way down wolfandy 1 Quote Link to comment Share on other sites More sharing options...
___ Posted March 22, 2020 Share Posted March 22, 2020 (edited) I would do this. Absorption voltage is 52.5V (There is no such thing as Bulk voltage. Bulk is the stage where the voltage has not yet reached the absorption level and we're throwing maximum current at it). Float at 51.8V. Reason: To properly balance, you need to be at or above 3.48V per cell, plus a small offset just to give the battery something to work with. But above 3.45V per cell little extra energy is stored, hence 51.8V (~ 15 * 3.45) is a good charge voltage. 51V is 3.4V per cell, which is also fine. But I would definitely raise the absorption voltage a tad. You will then see the SOC go to 100% too. Edited March 22, 2020 by plonkster SYC, Rclegg, wolfandy and 2 others 4 1 Quote Link to comment Share on other sites More sharing options...
2una Posted March 22, 2020 Share Posted March 22, 2020 (edited) Tagging along here as my Pylon bank is also tripping the master on odd occasion - moved it the other day to 52.5 + 52.0 & got it happen 24 hours later again so will now try what your suggesting there Plonkster & see if it will stop. Edited March 22, 2020 by 2una Quote Link to comment Share on other sites More sharing options...
wolfandy Posted March 22, 2020 Share Posted March 22, 2020 Thanks a lot for the feedback, gents I already increased Float to 51.5V yesterday to try to get closer to 100% SOC - but I will give Plonkster's values a try now Quote Link to comment Share on other sites More sharing options...
___ Posted March 22, 2020 Share Posted March 22, 2020 3 hours ago, wolfandy said: Plonkster's values Thank @Youda for his extensive research into these batteries. I'm plowing with his oxen, as we say in my mother tongue wolfandy 1 Quote Link to comment Share on other sites More sharing options...
wolfandy Posted March 22, 2020 Share Posted March 22, 2020 Then also thanks to @Youda Quote Link to comment Share on other sites More sharing options...
2una Posted May 9, 2020 Share Posted May 9, 2020 (edited) On 2020/03/22 at 2:22 PM, 2una said: Tagging along here as my Pylon bank is also tripping the master on odd occasion - moved it the other day to 52.5 + 52.0 & got it happen 24 hours later again so will now try what your suggesting there Plonkster & see if it will stop. So been set at 52.5/51.8 since i guess march 22nd Multi II 5000 - Firmware is 469 3 x 3000B Pylontechs Used only as backup - no solar Was doing the same on a Multi II 3000 Any further ideas to try? Edited May 9, 2020 by 2una Quote Link to comment Share on other sites More sharing options...
___ Posted May 9, 2020 Share Posted May 9, 2020 5 hours ago, 2una said: Any further ideas to try? Internal error usually means cell imbalance. Which is weird if it has been kept charged all the time. Only thing I've tried in the past that seemed to have worked was to discharge the batteries a bit and recharge them and see if the error clears. 2una 1 Quote Link to comment Share on other sites More sharing options...
2una Posted May 11, 2020 Share Posted May 11, 2020 On 2020/05/09 at 5:53 PM, plonkster said: Internal error usually means cell imbalance. Which is weird if it has been kept charged all the time. Only thing I've tried in the past that seemed to have worked was to discharge the batteries a bit and recharge them and see if the error clears. Turning the master off/on sorts it out till next time it appears again. It would also do it amongst load shedding times when it was getting discharge use so that also don't seem to rectify the problem. @wolfandy Is yours still doing this or you find a fix ? Quote Link to comment Share on other sites More sharing options...
wolfandy Posted May 12, 2020 Share Posted May 12, 2020 Am using 52.2V and 51.8V - and my system is running without any problems. But I am also cycling my Pylons every night Only slight oddity that I see every now and then is that the Pylon BMS reports 101% SOC Quote Link to comment Share on other sites More sharing options...
2una Posted May 12, 2020 Share Posted May 12, 2020 3 hours ago, wolfandy said: Am using 52.2V and 51.8V - and my system is running without any problems. But I am also cycling my Pylons every night Only slight oddity that I see every now and then is that the Pylon BMS reports 101% SOC Ok thanks Quote Link to comment Share on other sites More sharing options...
2una Posted May 14, 2020 Share Posted May 14, 2020 Will give 52,2/51.8 a try & see if any differant - logging this here so i have a date change to go back on Quote Link to comment Share on other sites More sharing options...
RETNEV Posted May 23, 2020 Share Posted May 23, 2020 Interesting response to Pylontech alarm from company rep. in the Victron community forum https://community.victronenergy.com/answers/50455/view.html The cause of this alarm message:Our battery has a kind of BMS logic:When the battery is not charged or discharged for 3 days,always in idle state. The battery will automatically shut down and go to sleep mode.Only when the battery is charged or discharged again, by then the battery will automatically activate. So when there is a battery to sleep mode and shut down, our Master battery will light up red light and send message to the inverter show there is an internal alarm. (You can check the first three days of the alarm record, the battery will be used once.) What I want to highlight fist is that. This is a normal BMS logic of our battery, to reduce unnecessary self discharge consumption loss of the system.it will not affect the normal use of the whole system or cause damage to the system. So don’t worry. This situation usually occurs when the inverter sets the battery to the backup power supply, or UPS mode. The battery is not used as often, and it is usually left unused after being charged to 100%. The solution: 1.Determine the working mode of on-site situation. If the customer does not want to use the back-up mode, please set the battery has priority over the public-grid to power the load. 2. If the customer only wants to use the battery as a backup power source, The customer can limit the inverter to charge the battery only up to 90% not 100%, so that the battery will not enter the standby state. Hope these information will help. Please let me know if you have more questions. 2una 1 Quote Link to comment Share on other sites More sharing options...
2una Posted May 24, 2020 Share Posted May 24, 2020 (edited) 14 hours ago, RETNEV said: Interesting response to Pylontech alarm from company rep. in the Victron community forum https://community.victronenergy.com/answers/50455/view.html The cause of this alarm message:Our battery has a kind of BMS logic:When the battery is not charged or discharged for 3 days,always in idle state. The battery will automatically shut down and go to sleep mode.Only when the battery is charged or discharged again, by then the battery will automatically activate. So when there is a battery to sleep mode and shut down, our Master battery will light up red light and send message to the inverter show there is an internal alarm. (You can check the first three days of the alarm record, the battery will be used once.) What I want to highlight fist is that. This is a normal BMS logic of our battery, to reduce unnecessary self discharge consumption loss of the system.it will not affect the normal use of the whole system or cause damage to the system. So don’t worry. This situation usually occurs when the inverter sets the battery to the backup power supply, or UPS mode. The battery is not used as often, and it is usually left unused after being charged to 100%. The solution: 1.Determine the working mode of on-site situation. If the customer does not want to use the back-up mode, please set the battery has priority over the public-grid to power the load. 2. If the customer only wants to use the battery as a backup power source, The customer can limit the inverter to charge the battery only up to 90% not 100%, so that the battery will not enter the standby state. Hope these information will help. Please let me know if you have more questions. What i'm seeing seems to support that & I'm still getting the alarm even set at 52.2/51.8 - i gave it load on the 21st to have the alarm go off again this am 24th. 14th i set it to 52.2/51.8 @plonkster - Cheif any idea a setting to put it at 90% to try? Edited May 24, 2020 by 2una Quote Link to comment Share on other sites More sharing options...
2una Posted May 24, 2020 Share Posted May 24, 2020 (edited) Also just seen this comment - would this be a possible usable approach to use remembering that i'm backup/UPS only? Quote Thanks for the explanation @Ned Yu (Pylontech). I noticed that the error would always appear exactly 3 days after the end of the last discharge/charge cycle. There is another way to prevent the error and keep the batteries charged at 100%. If the ESS assistant is loaded onto the Victron Multiplus, the system will draw small amounts of power from the battery and return it shortly afterwards. See battery voltage vs. current below: This prevents the battery from going into idle mode and generating the internal error alarm. https://community.victronenergy.com/comments/50458/view.html Edited May 24, 2020 by 2una Quote Link to comment Share on other sites More sharing options...
___ Posted May 25, 2020 Share Posted May 25, 2020 The idea of "holding" the SOC is in my opinion a flawed one, because SOC tracking is always an estimation of a chemical process. At the edges we can be fairly accurate, because we know the voltage rises as the cells fill up, but lower down LFP cells has a flat curve and you can easily end up slowly discharging a battery while you think you're holding the SOC constant. The only solution would be to keep them at a lower voltage, say 51V (3.4V per cell). Usually in a Victron system there is enough back and forth going on that it should not be problem, but if it is, there's three things I can think of. 1. If you're running "Keep Batteries Charged", you can (in VE.Configure) enable Dynamic current limiting for that AC input. This is actually meant for generators. What it does is when a larger load starts on the output, it uses the Multi to "cushion" the blow, so that the generator gets more of a gradual load increase. By using this you make the batteries do something every now and then. 2. Instead of using "Keep Batteries Charged", put the system into optimised mode, and then enable Scheduled charging. Set a charge schedule that runs evey day from midnight for 23 hours and 55 minutes. The effect would be that every day just before midnight it will discharge the batteries for 5 minutes, also avoiding the "error". 3. Ignore the error... 2una 1 Quote Link to comment Share on other sites More sharing options...
2una Posted May 25, 2020 Share Posted May 25, 2020 (edited) 1 hour ago, plonkster said: The idea of "holding" the SOC is in my opinion a flawed one, because SOC tracking is always an estimation of a chemical process. At the edges we can be fairly accurate, because we know the voltage rises as the cells fill up, but lower down LFP cells has a flat curve and you can easily end up slowly discharging a battery while you think you're holding the SOC constant. The only solution would be to keep them at a lower voltage, say 51V (3.4V per cell). Usually in a Victron system there is enough back and forth going on that it should not be problem, but if it is, there's three things I can think of. 1. If you're running "Keep Batteries Charged", you can (in VE.Configure) enable Dynamic current limiting for that AC input. This is actually meant for generators. What it does is when a larger load starts on the output, it uses the Multi to "cushion" the blow, so that the generator gets more of a gradual load increase. By using this you make the batteries do something every now and then. 2. Instead of using "Keep Batteries Charged", put the system into optimised mode, and then enable Scheduled charging. Set a charge schedule that runs evey day from midnight for 23 hours and 55 minutes. The effect would be that every day just before midnight it will discharge the batteries for 5 minutes, also avoiding the "error". 3. Ignore the error... Ok thanks Plonkster - For Option 3 I need to check but i have it in my head if mains fail whilst the master is in that alarm state that it fails to deliver battery power but maybe i'm wrong, will check next time it throws it. I'm not currently on ESS setup at all but thanks for those 2 options to think about moving to. I watched all of the ESS vid & there was nothing i saw that really jumped out to use. Edited May 25, 2020 by 2una Quote Link to comment Share on other sites More sharing options...
RETNEV Posted May 25, 2020 Share Posted May 25, 2020 1 hour ago, 2una said: Ok thanks Plonkster - For Option 3 I need to check but i have it in my head if mains fail whilst the master is in that alarm state that it fails to deliver battery power but maybe i'm wrong, will check next time it throws it. I'm not currently on ESS setup at all but thanks for those 2 options to think about moving to. I watched all of the ESS vid & there was nothing i saw that really jumped out to use. Hi @2una - I have actually checked and for me it works. The BMS activates immediately after power failure and all 3 of my Pylontechs operate through the master. Red alarm led comes on after 3 days again. 2una 1 Quote Link to comment Share on other sites More sharing options...
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