Jump to content


  • Posts

  • Joined

  • Last visited

  • Days Won


Everything posted by Ironman

  1. Is it possible to see this in a blue system? MPII, Venus, 4 * pylontech us3000...
  2. [sarcasm] Why is it that days with high power consumption correlates with cloudy days - and a serious loss of PV power - battery depleted by 11pm; while days with low power consumption correlates with no cloud cover and perfect PV power?
  3. I am running. Very similar setup, with the 250/100 MPPT, using 6000wp artsolar panels. 20 x 300w pure black panels. 4 x 5s. This was my solar power for yesterday: the MPPt just limits the output current to 100 amp by drawing less current from the panels. No problem.
  4. The Venus controller reads the battery State of Charge from the BMS of the pylontech batteries. So the system gets an accurate battery state of charge, and thus will ensure a much longer discharge time. You can also build your own controller with a raspberry and Venus image. The system will work without the venus, but the MPII will then try to judge the battery charge level by just reading the battery voltage. There are many tales of broken expectations when systems are set up like that - under load, the voltage drop in the batteries and cables cause the MPII to under-estimate the battery level badly, eventually switching off due to low battery voltage, while the batteries still contain a good charge. @plonkster - feel free to elaborate or correct me if I am wrong here.
  5. The rack has space for a third battery if we feel we need more runtime in future.
  6. We needed a UPS for a small office (about 8 PC's, server and network hardware) to be able to continue working through loadshedding (4-6 hours at a time). We are renting our office and did not want a permanent setup. Requirements: - Ultimate long term reliability - high quality brand - Expected lifetime: about 15 years for inverter and 7-10 years for batteries (expecting much more regular loadshedding while eskom repairs its infrastructure) - Backup system that works for many years without maintenance - Standalone system ( rack on wheels) - Ready to be moved to a new office if we have to move, OR be re-purposed into a solar home ESS system (just add MPPT and panels) If we bought an off the rack 3KVA UPS system with 6000 WH runtime, we could probably get it for about R20k. But I have a long history with cheap UPS systems - they never make it to 2 years - then you have to replace the batteries - at huge cost, labour - weekend time etc. At about 4 or 5 years the inverter's cheap capacitors start sweating and it becomes very unreliable - almost worse than not having a UPS. Not one lasts over 6 years - and in the process, the PC's that you are supposed to protect are subjected to many power spikes and failures due to the unreliable UPS. So we went this route - about 4X more expensive but we know it will last, and protect the sensitive equipment properly for many years: - Victron Multiplus 3000 - Victron Venus controller - 2 X Pylontech US3000 batteries - 19" computer rack on wheels - Small DB with input breaker, earth leakage on output, and two circuits on output. - DC Fuses, cables and building the rig (took about 5 hours). @Jaco de Jongh built this rig for me:
  7. Hey @Elbow ...we are on this forum for details details details, not mutual back slapping. Please tell us a bit about your system, the diagrams and documentation needed, and the process. Others want to learn and follow the same path. ... and congrats.
  8. https://www.fin24.com/economy/breaking-eskom-warns-it-will-stop-providing-daytime-power-to-bloemfontein-unless-it-gets-paid-20191125?mobile=true https://twitter.com/Eskom_SA/status/1198952306735288321/photo/1?ref_src=twsrc^tfw|twcamp^embeddedtimeline|twterm^profile%3AEskom_SA&ref_url=http%3A%2F%2Fwww.eskom.co.za%2FPages%2FLanding.aspx If I were a solar installer, I would temporarily move to Bloemfontein - everybody who could afford to add R100-200k to their home loan debt will be clamouring for a solar system. Most will go completely off grid - cutting off more and more of Eskom's income. This is a bit tongue in cheek - but a serious electricity supply situation is developing in one of our large metro's. Eskom wants to cut power every day from 6AM to 8PM. All the citizens that pay their accounts every month will suffer together with the few that has robbed/stolen/mismanaged the city's finances to cause this issue.
  9. So this is a 12V system. According to this you have a 1000W inverter... but the image shows 1500W printed large on the inverter. And you say it is 1200W... These varying specifications indicate a cheap brand that will lie to get you to buy their product. But sometimes they can work ok. Lets give the inverter the benefit of the doubt. Do you know what the low voltage cutoff of the inverter is? When trying to draw 650W from the inverter, it will be drawing about 720W (including inefficiencies) from the battery - and at 12V, that is 60 Amp. I hope you have very thick cables running from the batteries to the inverter. These cables must also be as short as possible, since any voltage drop over the cables is a much more pronounced loss at 12V than a typical 48V system. You can measure the DC input of the inverter with a cheap digital multimeter while drawing a load to see how that voltage drops. Also - Why do you say "inductive load"? Heaters are normally resistive loads. Inductive loads are normally motors, compressors, airconditioners etc. A resistive heater should be an easier load to carry than an inductive load which could have a large startup "surge" current. Can you upload photos of your battery wiring, and heater load so we can get a better idea of your setup?
  10. I have also used mixed panels for many years. The best way to run them: - Get panels that do not differ by more than 15%. - Make one string with each kind of panel. Do not mix different panel ratings in one string. - If possible, keep the strings separate and use separate MPPT's for each string. - If not, and you have to put these strings in parallel on one MPPT: it will hunt around and find the maximum power point for all panels together. It adjusts the voltage and current drawn from the panels in a "searching" algorithm, while testing the power delivered (volts X amps). As the voltage goes up, the current comes down. As the voltage goes down, the current goes up. And all the time it tests - what is the power - should the voltage go up or down? So the MPPT "hunts around" for the maximum power point. - Using mixed panels like this, the overall maximum power point voltage will be at the maximum power point (Vmp) of the weaker panels - the stronger panels will deliver their normal current, but at the (lower) voltage of the max power point of the weaker panels. More or less. So if you use 330 Watt and 375 Watt panels in parallel, you should get about the same as if you only had 330 Watt panels. The 375W panels will be derated to 330W each, as @Jaco de Jongh said.
  11. Not today. Bad clouds - solar production went down to 10W from a 6000W array, over lunchtime! I could not believe that mid day dark clouds could bring down solar output that much! The battery went up to 94%, so I think my problem is solved - but they did not stay there - I don't think they balanced the cells properly.
  12. Thanks for the fix. I did ask two times earlier in this thread why the graphic representation's battery level differed from the Pylontech's indicated level. For anybody that has this issue in future: the setting is under system setup: Mine was set to Multiplus - and somehow the multiplus has a completely different SOC level.
  13. mmm I never saw a SOC higher than 84% today. And even now there is a large difference in the graphic display of the Venus, and the Pylontech data: The one shows the SOC at 68% and the other at 84%... Something really weird happening here.
  14. And now this happens: The Venus display of the Pylontech battery shows 99%: While the overview graphic animation shows the battery at 83%: The voltage is still 52.0V. Maybe the battery voltage "spiked" to 52.5V quickly, and now the battery is in float, which is still at 52V. But then why does the Venus state the mode as "absorption"?
  15. Hi Youda How do you know this? Did you get inside information, or did you take a Pylontech apart? It seems like nobody else seems to really know the inside of these batteries. Also - battery balancing is not an instant thing? As in - the balancers basically waste energy as heat by drawing current from cells that are higher than other cells - and this will take some time to balance? So how long should it be kept at a "balancing" voltage?
  16. So I changed the charging settings to from Absorption 52V/Float 51V to Absorption 52.5V/Float 52V about 10 minutes ago. Uploaded new settings to MP II, downloaded again to confirm that the new settings are active. The remote console is still showing 52V - with no increase in charging current?
  17. My point exactly. Maybe they don’t know themselves, since the product has not existed for the expected lifecycle. Maybe it varies with temperature? Bottom line, I feel they should give better information regarding this. Here we have two developers that are in charge of (excuse the pun) the charging algorithms of these batteries from different charging systems and they don’t have proper guidelines for the resetting of the SOC.
  18. @Jaco de Jongh Agreed. According to the Pylontech sheet, the voltage can be higher. Thanks. It could be that Victron is setting the float voltage too low since they have to make provision for other modes of operation. The multiplus is a flexible inverter and can be used in many system configurations. Some of these configurations could cause the battery to need a lower float voltage setting than in my case. Where is the control voltage being measured? At the output of the MPPT? At the input of the Multiplus? Or from the Pylontech BMS? If they are all available, which one is chosen for the control loop? @plonkster I will send you the VRM stuff. Please go ahead. I was being over cautious.
  19. Please do not take this the wrong way - I appreciate your offer to try to find a solution ourselves, but I find myself in a position where It feels like a guessing game. The Pylontech batteries run on firmware with a set of rules. Somebody with proper knowledge of the programming and operation of the pylontech firmware will be able to tell us exactly how to solve this. Do we, as a market of pylontech consumers, not have a large enough market share to get them to be involved in this? if we increase the voltage, at some point it might cause a SOC reset, or it could start damaging the batteries. Which will happen first? And will Pylontech honor my guarantee? Both might happen - we could hit the SOC reset, but damage the batteries over a period of time. Or is there a fault in the Pylontech firmware? Should they not be the ones to fix this issue? If the SOC reset is set too high in the Pylontech firmware, they should solve it. Let us just think this issue through and try to get pylontech involved before acting. Like you said - it is just a BMS SOC reset, not a urgent issue. Does not have to be solved today. These batteries are a large part of my investment and they need to outlast the guarantee. If you, as Victron, have technical specs or guidelines from Pylontech about exactly what voltage will not damage the battery, we can go ahead. Please let me know.
  20. @plonkster @Coulomb My pylontechs (4XUS3000) has not been above 88% this week. And every day the maximum SOC after long periods of "float" at 52V is getting lower. Today it has been kept at 52V for almost 5 hours, and still the SOC shows only 84%. System: 6000W panels, 250/100 Victron MPPT, MP II 5000, running in ESS mode. There is a longer term graph of the battery SOC: Surely this is not right? The Pylontechs should be cel-balanced by now? Why is the maximum SOC getting lower and lower each day? 84% seems pretty low.
  21. Lol - I don’t do facebook. Closed my account three years ago. Don’t miss it at all.
  22. @plonkster - To me it looks like the Multi is delivering 2100W Before derating at the green circle - not 2400W?
  23. Ok, good to know. So does Victron know exactly which serial numbers are affected, or do they investigate it on a case by case basis, as they did with mine? Also: For everybody that ordered the Multiplus II 5000 - can you confirm that none of the HW Rev 4 units are affected?
  • Create New...