Adil Posted July 4 Share Posted July 4 I am having some issues with my 16kWh battery with Pace bms to show the right parameters on Deye 12KW 3 phase inverter. Battery Charge Voltage, Charge Current limit and Discharge Current limit showing on the inverter battery page do not correspond to the values set in the Pace bms software. Battery is communicating with inverter on CAN with Pylon protocol. There are two batteries connected in parallel. One is master and the other is slave with corresponding addresses of 1 and 2. I have tried Pylon RS485 protocol and it did not solve the problem. My understanding of the parameters is as under: Pack FullCharge Voltage should be equal to Battery Charge Voltage. Currently >>>(55.2v/57.6v) CHG OC Alarm should be equal to Charge Current limit. Currently >>>(130A/140A) DSG OC Alarm should be equal to Discharge Current limit. Currently >>>(130A/120A) Value of 280A for Charge Current limit and 240A for Discharge current limit is for two batteries. If I disconnect the second battery then these values will change to 140A and 120A respectively. Any help will be really appreciated. Quote Link to comment Share on other sites More sharing options...
Adil Posted July 6 Author Share Posted July 6 This is the screenshot I found in Gobel Power battery manual which also uses Pace bms. It shows which values are sent to the inverter It says in the manual: Some important values are sent to inverter, such as: A. CHG OC Alarm (A) : Max Charge Current Limit (CCL in Victron) B. DSC OC Alarm (A): Max Discharge Current Limit (DCL in Victron) C. Pack FullCharge Voltage (V): Max Charge Voltage Limit (CVL in Victron) Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 6 Share Posted July 6 1 hour ago, Adil said: A. CHG OC Alarm (A) : Max Charge Current Limit (CCL in Victron) that's reported to the inverter and shown correctly, right? 1 hour ago, Adil said: B. DSC OC Alarm (A): Max Discharge Current Limit (DCL in Victron) This, for 2 batteries would be 400A, however, the 12kW inverter would only need 240A * 50V = 12kW, so it will probably never show more than this, even if its available, since it should never be able to draw more than the 240A it is showing you... As for the Voltage, the cells at rest are probably no more than 3.3-oddV or so * 16 cells, I'm assuming, is around 53.somethingV , I'd assume, your 53.15V would be 3.321875V per cell, which is fair... do not think you will ever see LiFePO4's showing up as 54V or 55V, once charged, saturated and balanced, they quickly will drop to 3.3-odd V per cell once sitting idle. Quote Link to comment Share on other sites More sharing options...
Adil Posted July 6 Author Share Posted July 6 (edited) Quote that's reported to the inverter and shown correctly, right? No, it is not. As I mentioned above, all three values do not correspond to the display on the Deye inverter. The main problem I have is the Battery charge voltage of 57.6v which I have set to be 55.2v. I want the inverter to charge my batteries at 55.2v and when the voltage is reached, soak up the remaining power by reducing amperage. Charging with 57.6v has the potential to run into Cell over voltage protection of 3.65v. Edited July 6 by Adil Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 6 Share Posted July 6 34 minutes ago, Adil said: No, it is not. Explain, the photo of the inverter screen says 280A and 240A, the 280A is two of your batteries at 140A each as also shown in the battery screenshot, so explain what you mean here by "No, it is not."? The 240A, I gave you an explanation, think about it, it makes total sense as for the Voltage... that is the BMS telling the inverter what charge Voltage to use, which works out to 3.60V per cell, presumably a over voltage protection voltage or you may not even be able to change this, since, if you look at the voltage as it is being charged, it will be more like 54V or even lower and will only be able to rise, by the time the batter(y/ies) are close to full, by which time the charge current will also be dropping... Quote Link to comment Share on other sites More sharing options...
Sc00bs Posted July 6 Share Posted July 6 My understanding (could be wrong, is only what I have picked up in the past on the forum) is that the manually set voltages are fall back settings to be used in the event of a comms failure between the Inverter and BMS and that the battery BMS usually controls all the voltages. zivva 1 Quote Link to comment Share on other sites More sharing options...
Adil Posted July 7 Author Share Posted July 7 15 hours ago, Kalahari Meerkat said: Explain, the photo of the inverter screen says 280A and 240A, the 280A is two of your batteries at 140A each as also shown in the battery screenshot, so explain what you mean here by "No, it is not."? The 240A, I gave you an explanation, think about it, it makes total sense as for the Voltage... that is the BMS telling the inverter what charge Voltage to use, which works out to 3.60V per cell, presumably a over voltage protection voltage or you may not even be able to change this, since, if you look at the voltage as it is being charged, it will be more like 54V or even lower and will only be able to rise, by the time the batter(y/ies) are close to full, by which time the charge current will also be dropping... You are looking at the screenshot in the second post where CHG OC Alarm is 140A. My actual bms screenshot is in the first post where it is set to 130A. I understand your point that the charge limit of the inverter is 240A so it might not show any higher value even if it is set in the bms but I am still stuck with the voltage issue which is the primary problem. Every time my battery reaches 100%SOC it is usually because some over voltage protection is hit. The bms cuts off the charge amperes and as the voltage is higher than Pack FullCharge voltage of 55.2v it changes the SOC to 100%. My battery goes from 90% to 100% in five minutes. Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 7 Share Posted July 7 2 hours ago, Adil said: Every time my battery reaches 100%SOC it is usually because some over voltage protection is hit. The bms cuts off the charge amperes and as the voltage is higher than Pack FullCharge voltage of 55.2v it changes the SOC to 100%. My battery goes from 90% to 100% in five minutes. Ok, yes, well, I dislike how most of these BMS' determine 100%SoC, but surely, even when it says 100%, it continues to take current and balances the cells... ? Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 7 Share Posted July 7 16 hours ago, Sc00bs said: My understanding (could be wrong, is only what I have picked up in the past on the forum) is that the manually set voltages are fall back settings to be used in the event of a comms failure between the Inverter and BMS and that the battery BMS usually controls all the voltages. The settings are given by the BMS to the inverter, in this case, and not the Voltage/Current settings on the inverter you would use, if you used lead acid batteries or had no BMS comms... Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 7 Share Posted July 7 4 hours ago, Adil said: Every time my battery reaches 100%SOC it is usually because some over voltage protection is hit. The bms cuts off the charge amperes and as the voltage is higher than Pack FullCharge voltage of 55.2v it changes the SOC to 100%. My battery goes from 90% to 100% in five minutes. That would imply badly balanced cells... I think... Quote Link to comment Share on other sites More sharing options...
zivva Posted July 7 Share Posted July 7 From personal experience with a Pace BMS : - the Battery Charge Voltage displayed & used by Deye is Pack OV alarm set on the BMS : should be 56V in your case then. No idea where comes from your 57.6V that doesn't match any of your BMS setting ... - the Charge & Discharge current limits are equal to 95% of the CHG / DSG OC alarms As most BMS these days, SOC is reset to 100% when either 1 cell reaches OV alarm OR pack reaches OV alarm. That explains why your SOC jumps from 90% to 100% If your cells are unbalanced ... with a cell OV alarm set too low (3.50V) Maybe try those settings : Cell OV alarm : 3.65V Pack OV alarm : 56V Unless your cells are totally out of balance, that should leave enough time for the pack to reach 56V without a cell reaching 3.65V first then producing a SOC jump ... and increase cells unbalance in the long run ... Sc00bs 1 Quote Link to comment Share on other sites More sharing options...
P1000 Posted July 8 Share Posted July 8 (edited) My guess is that the slave battery is not balanced, and disconnects on cell ovp, then the master battery reaches all conditions for full pack reset (>55.2V and <2000mA). It will likely sort itself out over the course of a couple of weeks, if it does not, you might have to replace a cell. As a side-note: that battery temperature is way too high! Edited July 8 by P1000 Quote Link to comment Share on other sites More sharing options...
Adil Posted July 8 Author Share Posted July 8 18 hours ago, Kalahari Meerkat said: Ok, yes, well, I dislike how most of these BMS' determine 100%SoC, but surely, even when it says 100%, it continues to take current and balances the cells... ? It does continue balancing the cells but it only has a puny passive balancer which cannot do much. I have received Neey 4A active balancers which I am going to install very soon. 16 hours ago, Kalahari Meerkat said: That would imply badly balanced cells... I think... The maximum voltage difference at 100% SOC I have seen is around 200mv. It goes down with time when bms is balancing. Average is around 120mv. 9 hours ago, zivva said: From personal experience with a Pace BMS : - the Battery Charge Voltage displayed & used by Deye is Pack OV alarm set on the BMS : should be 56V in your case then. No idea where comes from your 57.6V that doesn't match any of your BMS setting ... - the Charge & Discharge current limits are equal to 95% of the CHG / DSG OC alarms As most BMS these days, SOC is reset to 100% when either 1 cell reaches OV alarm OR pack reaches OV alarm. That explains why your SOC jumps from 90% to 100% If your cells are unbalanced ... with a cell OV alarm set too low (3.50V) Maybe try those settings : Cell OV alarm : 3.65V Pack OV alarm : 56V Unless your cells are totally out of balance, that should leave enough time for the pack to reach 56V without a cell reaching 3.65V first then producing a SOC jump ... and increase cells unbalance in the long run ... Hmm. I am changing the parameters in the bms making Cell OV alarm to 3.6v and Pack OV alarm to 56.8v. I will monitor the battery for the next two days by using the memory function in the bms. I will report the conclusions here. Quote Link to comment Share on other sites More sharing options...
Adil Posted July 8 Author Share Posted July 8 39 minutes ago, P1000 said: My guess is that the slave battery is not balanced, and disconnects on cell ovp, then the master battery reaches all conditions for full pack reset (>55.2V and <2000mA). It will likely sort itself out over the course of a couple of weeks, if it does not, you might have to replace a cell. As a side-note: that battery temperature is way too high! Cells cannot be replaced. They are ultrasonically welded. And the battery is no more than a month old with Hithium 314Ah cells. I hope it sorts out itself. As for battery temperature, nothing can be done about it when ambient temperature hovers around 45°C. Quote Link to comment Share on other sites More sharing options...
zivva Posted July 8 Share Posted July 8 With that kind of temperatures, inverter & batteries would highly benefit from an AC ... Marginal cost vs shorten equipment life. Quote Link to comment Share on other sites More sharing options...
Adil Posted July 12 Author Share Posted July 12 (edited) I sniffed the CAN traffic of bms to inverter. I have attached the traffic picture and the document to interpret the values below. In ID 351, the first two bits 40 and 02 are battery charge voltage. As they are following little endian, it will be interpreted as 0240 in hex, which comes to 576 in decimal i-e 57.6v, which is what we are seeing on the inverter. So it is now confirmed that the 57.6v value is being sent by the bms to the inverter. I don't understand why the bms will do it. PbmsTools software which everyone uses to modify Pace bms doesn't seem to have any hidden settings. So I guess I have to find a new firmware for bms to handle this or someway to change the value going to the inverter. Thanks everyone. PYLON BMS Protocol _CAN_ _Can_20161103.pdf Edited July 12 by Adil BritishRacingGreen 1 Quote Link to comment Share on other sites More sharing options...
Tinbum Posted July 12 Share Posted July 12 9 hours ago, Adil said: I sniffed the CAN traffic of bms to inverter. I have attached the traffic picture and the document to interpret the values below. In ID 351, the first two bits 40 and 02 are battery charge voltage. As they are following little endian, it will be interpreted as 0240 in hex, which comes to 576 in decimal i-e 57.6v, which is what we are seeing on the inverter. So it is now confirmed that the 57.6v value is being sent by the bms to the inverter. I don't understand why the bms will do it. PbmsTools software which everyone uses to modify Pace bms doesn't seem to have any hidden settings. So I guess I have to find a new firmware for bms to handle this or someway to change the value going to the inverter. Thanks everyone. PYLON BMS Protocol _CAN_ _Can_20161103.pdf 76.1 kB · 0 downloads I use a teensy to change the CAN messages my Pylontech batteries send to my inverter- works really well. Quote Link to comment Share on other sites More sharing options...
Adil Posted July 13 Author Share Posted July 13 (edited) 6 hours ago, Tinbum said: I use a teensy to change the CAN messages my Pylontech batteries send to my inverter- works really well. I have a Teensy 3.1 lying in the parts bin somewhere. Are you using SN65HVD230 transceiver with it? Do you have details for the wiring, code, library etc? Edited July 13 by Adil Quote Link to comment Share on other sites More sharing options...
Tinbum Posted July 13 Share Posted July 13 5 hours ago, Adil said: I have a Teensy 3.1 lying in the parts bin somewhere. Are you using SN65HVD230 transceiver with it? Do you have details for the wiring, code, library etc? I used this as I needed 3 CAN busses, one for the battery, one for the inverter and the other for an Eltek charger. https://www.skpang.co.uk/products/teensy-4-1-triple-can-board-with-240x240-lcd-and-ethernet?_pos=5&_sid=efce14e84&_ss=r Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted July 14 Share Posted July 14 On 2024/07/12 at 1:40 PM, Adil said: In ID 351, the first two bits 40 and 02 are battery charge voltage. As they are following little endian, it will be interpreted as 0240 in hex, which comes to 576 in decimal i-e 57.6v, which is what we are seeing on the inverter. Mine isn't set to Lithium at the moment, but to Voltage... need to get some cells balanced... anyway, sniffing the BSL 8k2Wh battery I see the following... root@pi0wTwo0:~ $ candump can0 can0 35F [8] 00 00 36 01 00 00 00 00 can0 372 [8] 01 00 00 00 00 00 00 00 can0 373 [8] 3D 0D 4D 0D 1F 01 1F 01 can0 379 [8] A0 00 00 00 00 00 00 00 can0 374 [8] 31 20 3A 3A 31 33 00 00 can0 375 [8] 31 20 3A 3A 32 20 00 00 can0 376 [8] 31 20 3A 3A 32 20 00 00 can0 377 [8] 31 20 3A 3A 31 20 00 00 can0 35E [8] 42 53 4C 42 41 54 54 00 can0 35A [8] A8 AA A2 00 A8 AA 02 00 can0 351 [8] 21 02 B0 04 DC 05 E0 01 can0 355 [8] 64 00 64 00 10 27 00 00 can0 356 [8] 3B 15 82 00 8D 00 00 00 can0 35F [8] 00 00 36 01 00 00 00 00 can0 372 [8] 01 00 00 00 00 00 00 00 can0 373 [8] 3D 0D 4D 0D 1F 01 1F 01 can0 379 [8] A0 00 00 00 00 00 00 00 can0 374 [8] 31 20 3A 3A 31 33 00 00 can0 375 [8] 31 20 3A 3A 32 20 00 00 can0 376 [8] 31 20 3A 3A 32 20 00 00 can0 377 [8] 31 20 3A 3A 31 20 00 00 can0 35E [8] 42 53 4C 42 41 54 54 00 can0 35A [8] A8 AA A2 00 A8 AA 02 00 can0 351 [8] 21 02 B0 04 DC 05 E0 01 can0 355 [8] 64 00 64 00 10 27 00 00 can0 356 [8] 3B 15 82 00 8D 00 00 00 can0 35F [8] 00 00 36 01 00 00 00 00 can0 372 [8] 01 00 00 00 00 00 00 00 can0 373 [8] 3D 0D 4D 0D 1F 01 1F 01 can0 379 [8] A0 00 00 00 00 00 00 00 can0 374 [8] 31 20 3A 3A 31 33 00 00 can0 375 [8] 31 20 3A 3A 32 20 00 00 can0 376 [8] 31 20 3A 3A 32 20 00 00 can0 377 [8] 31 20 3A 3A 31 20 00 00 can0 35E [8] 42 53 4C 42 41 54 54 00 can0 35A [8] A8 AA A2 00 A8 AA 02 00 can0 351 [8] 21 02 B0 04 DC 05 E0 01 can0 355 [8] 64 00 64 00 10 27 00 00 can0 356 [8] 3B 15 82 00 8D 00 00 00 and the Voltage for this model & pace bum ms seems to call for 0x221, being 54.5V... don't have the RS232 cable nor WindoZe running near this thing to try and see what parameters are set on the BMS... ZS1SCI 1 Quote Link to comment Share on other sites More sharing options...
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