Screech Posted January 11, 2020 Share Posted January 11, 2020 Dear all I am using an MPP LV5048 inverter ( I have 3 inverters configured to work together in 3 phase mode) and a battery bank consisting of 16x Rolls flooded batteries model “S6 L16-HC” with the following battery related settings -Option 5 (Battery Type”: User defined -Option 12 (Voltage Point Back to Utility): 48V -Option13 (Voltage Point Back to Battery): 54V -Option 26 (Bulk Charge Voltage): 58.4 -Option 27 (Floating Charge): 53.5V -Option 32 (Bulk Charge Time): Automatic I am experiencing the following weird behavior: Everyday when the battery starts charging it start in Bulk Charge Mode but as soon as the Voltage reaches the Bulk Charge Voltage (58.4V) configured in option 26 the system switch to float mode (Voltage drops to 53.4-53.5). In others word the system does not enter or barely stay in absorption mode (charge battery with constant voltage equal to bulk charge voltage (58.4) with the result that my batteries only charge to approx 75 -80 % SOC and not 100%. The only way that I have been able to force the system into absorption mode in order to fully charge the battery bank is by changing option 32 (Bulk Charge mode) from “automatic” to a manual configured amount of time such as 480 minutes. So what is the recommended setting for option 32 (Bulk Charge time): Automatic or maunaully configured value? If automatic is the recommended value how can I solve above problem? For you reference I am putting below the compete config of the inverter Option Description Configured Value 1 Output Source Priority SBU (SBU Priority) 2 Maximum Charge Current 40 A 3 AC Input Voltage Range APL (Appliances) 5 Battery Type USE (user defined) 6 Automatically Restart when overload occurs Restart disable 7 Automatically Restart when over temperture occurs Restart disable 8 Output Voltage 120V 9 Output frequency 50Hz 11 Maximum Utility Charging 10A 12 Setting Voltage point back to utlity source when selecting "SBU Priority" or "Solar First" in program 1 48V 13 Setting Voltage point back to utlity source when selecting "SBU Priority" or "Solar First" in program 1 50V 16 Charger source priority OSO (Only Solar) 18 Alarm Control Alarm On 19 Automatically return to default display screen Return to default display screen 20 Backlight Control Backlight on 22 Beeps when primary source is interrupted AON (Alarm on) 23 Overload Bypass Bypass disable 25 Record Fault Code Record Disable 26 Bulk Charging Voltage 58.4V 27 Floating charging voltage 53.5 V 28 AC output mode 3 Phase Application 29 Low DC Cutoff Voltage 46.8V 30 PV Judge Condition ONE (One inverter) 31 Solar Power Balance Solar Power Balance Enable 32 Bulk Charging Time Automatically 33 Battery Equalization Battery Equaliation disabled 34 Battery Equalization Voltage 58.4V 35 Battery Equalized Time 60 36 Battery Equalized Timeout 120 37 Equalization interval 30 39 Equalization activated immediately disable Quote Link to comment Share on other sites More sharing options...
Coulomb Posted January 12, 2020 Share Posted January 12, 2020 (edited) On 2020/01/12 at 4:11 AM, Screech said: I am using an MPP LV5048 inverter ( I have 3 inverters configured to work together in 3 phase mode) So you are using three of these LV5048 split phase models? I've not heard from many split phase users. Is your 3-phase 208 V, or 415 V? Quote I am experiencing the following weird behavior: Everyday when the battery starts charging it start in Bulk Charge Mode but as soon as the Voltage reaches the Bulk Charge Voltage (58.4V) configured in option 26 the system switch to float mode (Voltage drops to 53.4-53.5). In others word the system does not enter or barely stay in absorption mode (charge battery with constant voltage equal to bulk charge voltage (58.4) with the result that my batteries only charge to approx 75 -80 % SOC and not 100%. Sadly, this is classic premature float bug behaviour. Weber and I have developed patched firmware to fix this, but we've never come across firmware for a split phase model. Quote The only way that I have been able to force the system into absorption mode in order to fully charge the battery bank is by changing option 32 (Bulk Charge mode) from “automatic” to a manual configured amount of time such as 480 minutes. As far as I know, this is your only option. It's not great, but at least it will charge your battery closer to 100% than otherwise. Quote So what is the recommended setting for option 32 (Bulk Charge time): Automatic or maunaully configured value? If automatic is the recommended value how can I solve above problem? For reasons that I can't understand, many users don't seem to be bitten too badly by this bug. So many aren't even aware of it. For you, yes, use a manual figure. What figure to use will have to be guess and refined with use. 60 min seems like a reasonable place to start. The problem with too much bulk (really absorb) charge time is that you might overcharge the battery some days (while still undercharging on others). You might also consider using the equalisation feature, set to run every day. One of the premature charge bugs is that time spent between the float and absorb voltage settings is counted as absorb time; it should only count time near the absorb voltage setting. I haven't checked the equalisation code to see if that's any better; I have an LFP battery, and use patched firmware based on factory firmware version 73.00, which doesn't have the equalisation facility. Quote For you reference I am putting below the compete config of the inverter As a point of interest, how did you enter that lovely table? Just pasted from a word processor? Your settings seem reasonable, apart from not using either timed absorb or equalisation. Oh, and setting 29 should be set to 46.0 V if you really want the "back to grid" setting (setting 12) to be 48.0 V. As it is, setting 12 is effectively 48.6 V (even though you can't set to other than full volt values). See FAQ question 2. Edited July 9, 2020 by Coulomb Quote Link to comment Share on other sites More sharing options...
Screech Posted January 12, 2020 Author Share Posted January 12, 2020 3 hours ago, Coulomb said: So you are using three of these LV5048 split phase models? I've not heard from many split phase users. Is your 3-phase 208 V, or 415 V? Sadly, this is classic premature float bug behaviour. Weber and I have developed patched firmware to fix this, but we've never come across firmware for a split phase model. As far as I know, this is your only option. It's not great, but at least it will charge your battery closer to 100% than otherwise. For reasons that I can't understand, many users don't seem to be bitten too badly by this bug. So many aren't even aware of it. For you, yes, use a manual figure. What figure to use will have to be guess and refined with use. 60 min seems like a reasonable place to start. The problem with too much bulk (really absorb) charge time is that you might overcharge the battery some days (while still undercharging on others). You might also consider using the equalisation feature, set to run every day. One of the premature charge bugs is that time spent between the float and absorb voltage settings is counted as absorb time; it should only count time near the absorb voltage setting. I haven't checked the equalisation code to see if that's any better; I have an LFP battery, and use patched firmware based on factory firmware version 73.00, which doesn't have the equalisation facility. As a point of interest, how did you enter that lovely table? Just pasted from a word processor? Your settings seem reasonable, apart from not using either timed absorb or equalisation. Oh, and setting 29 should be set to 46.0 V if you really want the "back to grid" setting (setting 12) to be 48.0 V. As it is, setting 12 is effectively 48.6 V (even though you can't set to other than full volt values). See FAQ question 2. Yes I am using 3x LV5048 to create a 208V 3-phase system (each phase is 120V). I see that many of the issues that I am facing have been fixed by your patched firmware version. I had several email exchange session with the support team of MPP solar and even though I told them several times that I suspect that my problems (low voltage warning as soon as my battery is at 48.8V, not taking voltage sag into account due to load with the result that it switches from battery to load to early and charging problem) are firmware related they never admitted this neither could they give me a good explanation for the behavior I was experiencing. I am running version 61.00 and according to the MPP Solar that is the latest version for the inverter. So if I understand you correctly you do not have a firmware patch for my type of inverter? What would you need in order to create a patch for this type of inverter? Last but not least I created the config table in Excel and pasted it in the forum. Finally I have been using the inverter for 2 weeks and I have to admit that they are performing very well other excluding the above mentioned issues that are all fixed by your patched firmware. If I could get solution to these firmware issues then I would definitely give the inverter a 10. Screech Quote Link to comment Share on other sites More sharing options...
Coulomb Posted January 12, 2020 Share Posted January 12, 2020 6 hours ago, Screech said: I am running version 61.00 and according to the MPP Solar that is the latest version for the inverter. So if I understand you correctly you do not have a firmware patch for my type of inverter? Yes, we certainly don't have anything like that. The hardware must be quite different, with two (presumably half power) inverters instead of one (for the two 120 V outputs). Quote What would you need in order to create a patch for this type of inverter? We'd need a firmware update file for 61.00 or similar. Since you already have the latest version, it seems very unlikely that they will send you one, and your supplier would be the only source. We'd only be able to do the premature float bugs, because they are such simple patches that we don't need extensive testing, and of course, we can't do any testing at all. Quote Link to comment Share on other sites More sharing options...
Screech Posted January 12, 2020 Author Share Posted January 12, 2020 12 hours ago, Coulomb said: Your settings seem reasonable, apart from not using either timed absorb or equalisation. Oh, and setting 29 should be set to 46.0 V if you really want the "back to grid" setting (setting 12) to be 48.0 V. As it is, setting 12 is effectively 48.6 V (even though you can't set to other than full volt values). See FAQ question 2. So if I understand the FAQ correctly: The effective value of option 12 is the value of option 29 +2V? Finally I have also noticed that the SOC indicator on the inverter is based on the measured voltage of the battery which is often off. For example as soon as the battery enters float stage the SOC indicators drops form full to only 2 stripes (65%). Any better solution to get a proper SOC reading? Quote Link to comment Share on other sites More sharing options...
Coulomb Posted January 13, 2020 Share Posted January 13, 2020 11 hours ago, Screech said: So if I understand the FAQ correctly: The effective value of option 12 is the value of option 29 +2V? It's the higher value of setting 12 and (setting 29 plus 2.0 V). So when setting 29 is within 2.0 V of setting 12, yes, the effective value is setting 29 plus 2.0 V. 11 hours ago, Screech said: Finally I have also noticed that the SOC indicator on the inverter is based on the measured voltage of the battery which is often off. ... Any better solution to get a proper SOC reading? Yes, use ICC and an external Victron BMV battery monitor. But I don't know if ICC will support an LV5048. My guess is that you could tell ICC that you have one of the supported models and it would be fine, but I can't be sure. If you are happy reading the small BMV display directly, you can use it without ICC, and simply ignore the SOC reported by the inverter. However, the inverter will in that case still switch over to grid and back to battery based purely on the battery voltage. When using ICC, it can switch at accurate SOC points. Quote Link to comment Share on other sites More sharing options...
Screech Posted January 20, 2020 Author Share Posted January 20, 2020 I cannot find a contact for ICC on there site as I have send them an email but have not heard anything back yet. DO you have a contact # or is it only mail? Quote Link to comment Share on other sites More sharing options...
RikH Posted January 21, 2020 Share Posted January 21, 2020 On 2020/01/20 at 7:21 PM, Screech said: I cannot find a contact for ICC on there site as I have send them an email but have not heard anything back yet. DO you have a contact # or is it only mail? [email protected] Johan helped me with my questions when I needed info before I puchased the ICC. Quote Link to comment Share on other sites More sharing options...
Screech Posted February 2, 2020 Author Share Posted February 2, 2020 Coulomb or any one , I have purchased ICC and also a BMV-702. The solution works good however switching between battery and grid does not seems to work. Is there anything special that you need do? For testing purposes I have used a value of 88% for to grid and 92% for battery. Another thing also on the BMV I can read the battery temperature (I have purchased the temp sensor) but ICC keeps reporting a value of 0. Any experience using the temperature sensor on the BMV ? Quote Link to comment Share on other sites More sharing options...
Coulomb Posted February 2, 2020 Share Posted February 2, 2020 5 hours ago, Screech said: I have purchased ICC and also a BMV-702. The solution works good however switching between battery and grid does not seems to work. Is there anything special that you need do? I don't use ICC, but I seem to recall that you need to set the low DC cutoff voltage value (setting 29) quite low, or maybe you need special "let me do the talking" values for settings 12 and 13 (back to grid and back to battery voltage settings). I think the details are on the ICC website. The other possibility is that the LV5048 models aren't used in South Africa where ICC is developed. They might require different settings; you may need to plead with Manie to implement some changes specific for that model. Quote Link to comment Share on other sites More sharing options...
Screech Posted February 24, 2020 Author Share Posted February 24, 2020 In the mean time I have ICC and BMV-702 working nicely together etc. Now since there does not seem to be a fix for the "premature float bug" for my MPP Solar LV5048 My question know is: Can I rely on the Victron BMV 702 SOC value to determine if the battery bank is correctly getting fully charged? If the Victron BMV can correctly indicates if the battery bank is getting fully charged then I assume that I do not have to worry about undercharging the batteries or are there other negative consequences of the "premature float bug"? Screech Quote Link to comment Share on other sites More sharing options...
Coulomb Posted February 24, 2020 Share Posted February 24, 2020 15 minutes ago, Screech said: In the mean time I have ICC and BMV-702 working nicely together etc. Excellent. 15 minutes ago, Screech said: Can I rely on the Victron BMV 702 SOC value to determine if the battery bank is correctly getting fully charged? In this sense, yes: if you have the settings in the BMV correct (mainly the battery capacity, and the Peukert effect setting, perhaps the termination current), and it consistently says that you are achieving 100% SOC at least most days, then you can rely on your batteries being adequately charged. Quote If the Victron BMV can correctly indicates if the battery bank is getting fully charged then I assume that I do not have to worry about undercharging the batteries Yes. Quote or are there other negative consequences of the "premature float bug"? No. Murdering your battery is the "only" consequence Quote Link to comment Share on other sites More sharing options...
Screech Posted February 24, 2020 Author Share Posted February 24, 2020 40 minutes ago, Coulomb said: Excellent. In this sense, yes: if you have the settings in the BMV correct (mainly the battery capacity, and the Peukert effect setting, perhaps the termination current), and it consistently says that you are achieving 100% SOC at least most days, then you can rely on your batteries being adequately charged. Yes. No. Murdering your battery is the "only" consequence OK but murdering my batteries will only take place if my batteries are consequently being undercharged right? not if they are fully charged. Quote Link to comment Share on other sites More sharing options...
Coulomb Posted February 24, 2020 Share Posted February 24, 2020 1 minute ago, Screech said: murdering my batteries will only take place if my batteries are consequently being undercharged right? not if they are fully charged. Yes. If fully charged most days, you should have normal battery life, barring other problems of course. Chronic undercharging kills lead acid batteries. There are no other consequences of the charge bug that I know of. Quote Link to comment Share on other sites More sharing options...
Screech Posted February 24, 2020 Author Share Posted February 24, 2020 Thanks you Quote Link to comment Share on other sites More sharing options...
Screech Posted February 25, 2020 Author Share Posted February 25, 2020 Coulomb, Question: I am using Rolls Batteries for my battery bank (model S6 L16-HC) (for your reference I am attaching the datasheet) and during a discussion\ support case with them they told me that I should have the bulk charge voltage set to 60V. However the maximum supported bulk charge voltage on the inverter is 58.4V (at least with the original firmware). Is there a way to increase this value? What has been your experience with this? Urvin Rolls S6 L16-HC.pdf Quote Link to comment Share on other sites More sharing options...
Coulomb Posted February 26, 2020 Share Posted February 26, 2020 On 2020/02/25 at 11:11 PM, Screech said: However the maximum supported bulk charge voltage on the inverter is 58.4V (at least with the original firmware). Is there a way to increase this value? No, there are 64V models and 58.4V models. They have a different transformer turns ratio, and different trade-offs. You can't change one to the other. I may have time to check your battery datasheet later, sorry. Quote Link to comment Share on other sites More sharing options...
RikH Posted February 27, 2020 Share Posted February 27, 2020 19 hours ago, Coulomb said: I may have time to check your battery datasheet later, sorry. In the mean time I did. It says charging voltage per cell: 2,45 - 2,5 volt. That means you need your charging voltage set to 58,8 - 60 volt and as stated above your charger isn't capable to do so. Quote Link to comment Share on other sites More sharing options...
Coulomb Posted February 27, 2020 Share Posted February 27, 2020 On 2020/02/25 at 11:11 PM, Screech said: I should have the bulk charge voltage set to 60V. However the maximum supported bulk charge voltage on the inverter is 58.4V It looks like these batteries are like the Trojans: they need a really high absorb voltage. That's the reason that Voltronic produced the 64 V models. However, split phase is not very common around the world, so they don't have a 64 V version of the split phase inverter-charger. Perhaps some Trojan owners can comment, but I think you might be able to charge them adequately at 58.8 V for a longer absorb time. Otherwise, those batteries and your inverter-charger are just not compatible. Quote Link to comment Share on other sites More sharing options...
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