nightbyte Posted August 28, 2020 Posted August 28, 2020 I have a Mecer Axpert King inverter with 2 Shoto Lithium-ion (LFP) SDA10-48100L5 batteries (which I believe are 15S). The batteries are paralleled in a Master and Slave cascade. The cascade communication is RS485/RJ45 wired as per the user manual. User manual values are: Charging; minimum 53.2V, typical 56.4V and maximum 57.5V BMS total system protection for high voltage is 54.0V alarm, with protection at 54.75V I am very much a novice when it comes to Solar systems and have obtained much guidance from this Forum. When I set my system to the 56.4V charging value, the 4 green charge level and the run LED illuminated and stayed steady, seeming to indicating (from the manual) an over voltage protection condition. As soon as I changed the setting to 53.2V the condition normalized and has not reoccurred. I then tried different settings up to 53.8V without a re-occurrence of the condition. At 54.0V it again occurred and I have concluded that this was the BMS initiating the alarm condition and that the BMS was doing exactly as programmed. I have therefore set my charging value to 53.2V. This conforms to the manufacturer’s minimum setting, maintains warranty and on a cell level is 3.547V. The critical maximum upper level for LFP cells is I believe, 3.65V. I hope that this setting will allow the batteries to safely reach 99.75% SOC with a small safety margin. I understand that on reaching the fully charged value, the batteries enter a condition called Float, at which they spend much of their time. Is it necessary to hold them at the charge voltage level? Forum information on this topic, from many experienced members suggests that it is not necessary, or desirable and recommend Float be set at between 51.8V and 52.4V, allowing a greater safety margin under the critical 3.65V cell value. I have therefore set the Float on my system to 52.2V. My user manual does not address Float settings. My system has been operating on these settings for a few weeks now (tail end of winter). I hope that Forum members will comment so that I may gain from their greater knowledge and insight, as I do not want to damage my batteries. Quote
nightbyte Posted August 29, 2020 Author Posted August 29, 2020 Thank you for responding. Unfortunately that model is not 16s. Quote
hannesk Posted September 17, 2020 Posted September 17, 2020 HI nightbyte, I also have 2 X of the same Shoto batteries in parallel, using a Victron Easy solar. Where did you get the user manual you mention "The batteries are paralleled in a Master and Slave cascade. The cascade communication is RS485/RJ45 wired as per the user manual." I do not have any communication between the batteries, they are only connected in parallel and of course I use + from one battery and - from the 2nd. I have no idea what the SOC LED's mean, do you have more information? Quote
nightbyte Posted September 17, 2020 Author Posted September 17, 2020 I received a User Manual in the box with the battery. Go to who ever supplied the batteries to you, they must have your User Manual. Quote
KGS Posted March 21, 2022 Posted March 21, 2022 My system comprises a 5.1kv shoto lithium battery and a growatt inverter connected to both Eskom and solar panels. My problem is that sometimes the system fails in that the battery goes into sleep mode and no power is supplied to home. It seems to me that the inverter is not charging the battery in certain instants. Is there a setting that may be incorrect or what? Thanks KGS Quote
nightbyte Posted March 21, 2022 Author Posted March 21, 2022 KGS could you please provide a bit more backround on how and when this occurs. Generally, the built in and factory set Shoto - Battery Monitoring System - (BMS) will do this to protect the battery at a predetermined low voltage over which the user has no direct control. The inverter also has settings, which allows you some control over charging, voltage cut out, and alarm points. Without knowing more about the specific incidents you refer to, it is difficult to be more specific in giving advice. However, that said, I would first study your inverter's manual, which should guide you on the correct settings. I do not have a Growatt inverter so I do not know its cut off, and back to system settings. Also check the Shoto manual which has guidace on the minimum voltages, that if exceeded will see the BMS kick in to protect the battery. Providing the inverter is not defective, it would seem that you have a setting problem. Request a forum member with a Growatt inverter to assist you with their settings, would be the place to start. Quote
KGS Posted March 23, 2022 Posted March 23, 2022 (edited) Thank you. Could it be caused by discharge overload or solar charge overload? Would a second battery assist in ensuring this does not happen again. I have a 5 kw inverter, 4 kw solar panels and 5 kw battery. Edited March 23, 2022 by KGS Quote
GTP Posted March 23, 2022 Posted March 23, 2022 I have a single Shoto battery 5.12. In terms of settings (by voltage), i cannot say. My battery is coonected by CAN port to my inverter, and the battery BMS determines the charge and discharge rates. My installer simply set the max current to charge and discharge at 40a. Apparently this influences how the bms does its thing. I couldnt tell you if it is right or wrong. It just seems to work.. so I am not questioning it. That and I leave settings to my installer mostly. There was a question abive about the SOC led lights and their meaning. So 4 led's each represent 25% SOC. From left to right they represent 25, 50, 75 and 100% SOC. If you have a single flashing LED, it means the battery is somewhere under 25% and charging. If as an example you have 2 solid lights and a flashing third led, it means the battery is definitely at 50% and charging up to 75%. All lights out and a flashing run led means it is at 100%. I normally use the value on the inverter though. It seems qyite accurate given the comms Quote
Keithdevilliers Posted October 10, 2022 Posted October 10, 2022 Hi, I only see my one battery’s value on SolarmanSmart? Lights are on but it does not include values on monitoring? please advise? Thank you Quote
jumper Posted October 17, 2022 Posted October 17, 2022 (edited) On 2022/10/10 at 4:34 PM, Keithdevilliers said: Hi, I only see my one battery’s value on SolarmanSmart? Lights are on but it does not include values on monitoring? please advise? Thank you Do you have a communication cable between the batteries? Are your master/slave DIP settings correct as per the manual? Edited October 17, 2022 by jumper Quote
wendl Posted February 20, 2023 Posted February 20, 2023 My shoto 5.12kw doesnt want to connect to my bms communication of the Growatt inverter 5kw Es . Keep gving me error 4. Currently i run it on user mode but then when its loadshedding the battery only charge up to 75%. What can i do ? Quote
nightbyte Posted February 22, 2023 Author Posted February 22, 2023 On 2023/02/20 at 8:46 PM, wendl said: My shoto 5.12kw doesnt want to connect to my bms communication of the Growatt inverter 5kw Es . Keep gving me error 4. Currently i run it on user mode but then when its loadshedding the battery only charge up to 75%. What can i do ? Good day to you Wendl, I need to ask you a few questions to be able to understand your difficulties. I hope you don't mind. Did you receive a Shoto manual with your battery? The Shoto 5.12kW has a specific set of communication requirements and switch settings listed in the 5.12kW manual. That would be the first step to comply with, and may resolve the communication issue. If you did not receive a manual, there were copies on the forum a little while ago. For the moment running on user mode is fine, until the other issues are resolved. Your battery is a 16 cell and has a charging profile of 54.0v to 56.4v The maximum safe setting for voltage is 56/16 = 3.5v per cell. I suggest you check your inverter's existing charge settings and then adjust in the range 54.0v to 56.4v. A lithium battery has a very flat charging curve which becomes very steep towards battery full condition. the difference between 85 and 100% full is less than a fraction of a volt. Most batteries have reached their full potential at around 85% and there is very little to be gain by going higher. Also lithium's can deteriorate if held at 100% capacity, the ideal maximum is just below 90%. holding at higher levels will reduce the battery's life span. When loadshedding kicks in you will notice a sudden and steep drop in capacity as the battery comes down from the steep end of the charging curve. As I mentioned a drop of 1 volt will cause the a rapid initial loss of capacity, thereafter on the flat part of the curve a gradual decline. That is why charging to above 90% has no real benefits. Your error 4 is likely to be resolved by correcting the comms issue, see what the Growatt manual says about that specific error. Kind regards nightbyte Quote
gtheophi Posted May 1, 2023 Posted May 1, 2023 Hello. I currently have 2x Shoto SDA10-48100-L5 batteries 48V (4.8KW battery). I want to grow my system and when I try to source that same model, Im told that the battery is now a 51V with that same model number and that it supplies 5.12KW. I'm not sure of a lot of things, but mostly, if I do buy the new ones, can I safely connect these in parallel to each other with the ones that I currently have also? Quote
jumper Posted May 2, 2023 Posted May 2, 2023 9 hours ago, gtheophi said: Hello. I currently have 2x Shoto SDA10-48100-L5 batteries 48V (4.8KW battery). I want to grow my system and when I try to source that same model, Im told that the battery is now a 51V with that same model number and that it supplies 5.12KW. I'm not sure of a lot of things, but mostly, if I do buy the new ones, can I safely connect these in parallel to each other with the ones that I currently have also? Unfortunately I don't think it will work due to the different charging voltages necessary, either the 48V will hit overvoltage if you charge with the voltage for the 51.2V or the 51,2V battery won't charge properly if you use the charge voltage for the 48V battery. Mixing batteries with different capacities can work, but not with different voltages. Quote
nightbyte Posted May 2, 2023 Author Posted May 2, 2023 Good morning to you gtheophi. Your existing batteries are 15 cell the 5.12kWh battery is a 16 cell, so there are internal differences and the BMS is unlikely to be identical. If you intend to link the batteries with communication cables, as master and slave as indicated in the the Shoto installation guide, there will be issues. The settings for the 5.12kWh battery are quite different to that of the 4.8 kWh battery, and the chance of not being able to fully utilise the full capacity of the 51.2 kWh is most likely. As a BMS is essentially the safety guard for your batteries, it is in my opinion that anything that compromises this would amount to an unsafe system. So in summary: It would be unsafe, in my opinion. You would not be able to fully use the capacity you have paid for. There would be issues in communicating between the two battery types. Your battery warranties would also be placed at risk. The 15 cell SDA10-48100-L5 batteries 48V (4.8KW battery) is still available in the RSA from various sources at competitive prices (for example, West Coast Solar). Perhaps other members of the Forum would also be kind enough to give their views as this issue must affect a number of Forum members. Kind regards Nightbyte Quote
nightbyte Posted May 2, 2023 Author Posted May 2, 2023 Suggest you request advise from the SA importers of Shoto batteries: Email address: Shoto Batteries South Africa (importers) [email protected] Quote
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