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mojive

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  1. Like
    mojive reacted to Youda in Youda's off-grid LAB   
    Hi guys,
    based on the fact that many forum users are trying to understand how to use Pylontech batteries efficiently, I've extracted some of the internal configuration values. It's from a stack of 8xUS3000. What instantly catched my eye are especially these values. So I added a couple of my comments and thougths:
    Total Num                 : 8                    //Number of maximum daisy-chained bricks supported by the firmware.  
    Present Num            : 8                     //Number of actually daisy-chained (RS485) bricks.
    Shut time                  : 72.0 H            //If the brick is not charged/discharged for 3 days, it will auto-power off.

    Balance Volt             : 30 mV
    Balance Start           : 3360 mV       //Looks like the BMS is able start balancing cells at this voltage it's not
                                                              //a static top-balancing, as I know that the BMS chip is able to stop balancing
                                                              //at a much higher voltage, if all the cells are at roughly the same voltage level.

    Recommend chg voltage    : 53250    mV   //This is what inverters like Axpert are reading
                                                                           //from the BMS and using as CC.
    Over VoltageR           : 51000 mV                 //Strange, that this is triggered at 51V, given
                                                                           //the recommended CC=53.2V.
    High VoltageR           : 52500 mV                
    High Voltage             : 53900 mV                 //Just 650mV of margin between recommended CC=53.2V and alarm.
    Over Voltage             : 54000 mV                 //Just 750mV of margin between recommended CC=53.2V and panic.
     
    A complete list goes here. Please note that the column "Battery" means actually a CELL while the column "Power" means a single US3000 BRICK:
    Protect Attribution --------------------------------- Item Battery Power Over Voltage : 3700 54000 mV Over VoltageR : 3600 51000 mV High Voltage : 3650 53900 mV High VoltageR : 3500 52500 mV Low Voltage : 3050 46000 mV Low VoltageR : 3100 47000 mV Under Voltage : 2900 44500 mV Under VoltageR : 3250 49000 mV Sleep Voltage : 2500 38000 mV Charging OT : 61000 61000 mC Charging OTR : 55000 55000 mC Charging HT : 59000 59000 mC Charging HTR : 55000 55000 mC Charging LT : -9000 -9000 mC Charging LTR : -5000 -5000 mC Charging UT : -11000 -11000 mC Charging UTR : -5000 -5000 mC Discharging OT : 61000 61000 mC Discharging OTR : 55000 55000 mC Discharging HT : 59000 59000 mC Discharging HTR : 55000 55000 mC Discharging LT : -9000 -9000 mC Discharging LTR : -5000 -5000 mC Discharging UT : -11000 -11000 mC Discharging UTR : -5000 -5000 mC Charging OC : 102000 mA Charging OC Alarm : 50000 mA Charging OC AlarmR : 40000 mA Discharging OC : -100000 mA Discharging OC Alarm : -50000 mA Discharging OC AlarmR : -45000 mA OC Delay : 15000 mS OC Release : 60000 mS Charging OC2 : 200000 mA Discharging OC2 : -200000 mA OC2 Delay : 100 mS OC2 Release : 60000 mS Discharging SC : -400000 mA SC Delay : 0 mS SC Release : 60000 mS Charging Max Cur : 10000 mA Balance Start : 3360 mV Balance Volt : 30 mV Shut time : 72.0 H BUV/PUV time : 2400 S Sleep ctrl state : OFF Sleep every day StartTime : 20:00 EndTime : 08:00 HwSleepInfo HwSleepStatus : OFF HwSleepTime : 6 S HwWakeupTime : 60 S Data Save every day StartTime : 00:00 EndTime : 23:59 Save Interval : 1800 S  
    Power System Information --------------------------------- System is idle Total Num : 8 Present Num : 8 Sleep Num : 0 System Volt : 49381 mV System Curr : -367 mA System RC : 352367 mAH System FCC : 585266 mAH System SOC : 60 % System SOH : 99 % Highest voltage : 3294 mV Average voltage : 3292 mV Lowest voltage : 3290 mV Highest temperature : 23000 mC Average temperature : 21875 mC Lowest temperature : 21000 mC Recommend chg voltage : 53250 mV Recommend dsg voltage : 47000 mV Recommend chg current : 296000 mA Recommend dsg current : -296000 mA Hope this helps all the young scientists that are developing their own monitoring and control solution for the batteries and inverters
    Youda
  2. Thanks
    mojive reacted to Energy-Jason in Dear PF Community   
    Dear all. 
    Firstly I would like to wish you all a safe and happy holiday break. I appreciate every single member and their contribution to making this a great, peaceful and happy platform to enrich each other with knowledge and advise. This was the goal when I started in 2013 with myself as 1 member.
    As the aviation industry is a very uncertain career I started the powerforum store about 2 years ago. I don't and will never request any member of this forum to be obligated to purchase from the store. There are many other commercial suppliers that offer just as great service.
    Since the beginning in 2013 , every member that has joined has been checked and manually been clicked on to be accepted to the community. There are so many spam individuals out there that want access to post unsavory topics. 
    Some of these individuals sometimes get through as they have a perfectly looking Gmail email addresses and locations.
    I have tried many different types of automatic spam filters but none are as good as checking with the human eye.
    Okay to the point 🤣 : if any members notice a scam or spam member posting I ask you to make use of the report button. Please see the attached image. I require two members to report the post to be automatically hidden for moderation.
    The members who have reported the post are also logged. So don't go reporting and hiding a freindly debate. ;D !
    This will help me greatly as I constantly have my phone in my pocket checking for scammers to protect our community.
    I would like to say thank you again for making this community great and also we nearly at 20 000 members!
    Have a safe and restful holiday break.
    Thank you all.
    Sincerely
    Jason Back
     
     

  3. Like
    mojive reacted to isetech in Earth Leakage tripping after inverter upgrade, why?   
    One of the most common faults with earth leakage units ... mixing up neutrals and series connecting earth earth leakage units. 
    Add in an inverter with bonded earth/neutral ... even semi skilled sparkies get confused.
    Understanding the SANS regs helps with positioning of the earth leakage in the circuits. 
    One of the most common comments I hear ... "but it has worked for years now suddenly".
    Make sure the earth leakage devices are not in series and make sure the neutrals and allocated to the correct neutral bar ... then make sure you earth neutral bond is before the earth leakage ... as close to the inverter as possible. 
    I still need to see one of those external neutral/earth bonding units.  
     
  4. Like
    mojive reacted to BritishRacingGreen in Earth Leakage tripping after inverter upgrade, why?   
    Hi @Nic Holmes, I am of the opinion that your new inverter has an automatic  earth bonding  relay arrangement , something your old inverter didn't have.  
    Further to this , if your inverter output circuits has a neutral that is wrongfully connected to the neutral of the circuits that is fed from the main ELB , then you will have this failure mode. In this case the following happens :
    When the input grid to inverter is lost , the earth bonding relay bond neural to earth at the inverter.
    However , the loads on the Main ELD have now two return paths, that of the neutral of the ELD , AND that of the inverter earth bond. Current flowing through the inverter earth bond is not seen by the ELD, and trips.
    If you have a suspicion that this may be the case , then you can test it as follows:
     
    1 isolate the inverter output from its loads by means of the circuit breaker. In this manner the load neutral is isolated from the inverter.
     
    2 then remove incoming grid to input of the inverter.
     
    3 if the ELD does not trip it's a dead giveaway you have mixed up neutrals 
    Good luck
     
     
     
     
     
  5. Like
    mojive reacted to ___ in Earth leakage trips   
    This is very difficult to do in an urban environment, as we commonly have TN-S earthing and the bond is at the transformer down the street :-)
    Additionally your earth wire should only carry fault current, never any working current. This means you can never put in a second bond (even if there are no ELBs that would trip), because from that point on you have parallel paths for the neutral current and some of it will run on the earth wire instead.
    So the trick is to ensure that at any point in time only one bond is "active", and that generally means you engage your own bond when in inverter mode, and remove it again when in grid mode, exactly as @Chris Hobson explained above.
    The trouble with all this is that it really doesn't explain why some ELBs are so temperamental with inverters. They are supposed to be residual current devices. They work on an imbalance. In simplest terms, what you do is make a big electromagnet (think back to school times) by wrapping a wire around a big old piece of iron, except that you wrap two windings on the same piece of iron. The two windings have the same amount of turns and are in opposite directions so that they cancel each other out. The magnetic field generated by the one neutralises the magnetic field generated by the other if the currents are the same and there is no residual magnetism. If there is an imbalance, it turns into a small electromagnet that can perform a physical task of some kind: tripping a breaker.
    (Reality is a tad more complex of course).
    But... because RCDs are sometimes temperamental, one fix is to put the inverter on the "clean" side. It can be done safely. If the inverter case itself is properly earthed, then you still have protection, and I believe this can be done to regulations, but I would still want an electrician to sign it off, and as far as I know SANS actually requires an RCD/ELB on the input side of a UPS so I still prefer to do it that way.
  6. Like
    mojive reacted to WannabeSolarSparky in Off-Grid Trial For August/September 2022   
    Hi there @TiaanSmit
    This is my own custom dashboard with some major input from @Bloubul7
    Here is the link:
    https://powerforum.co.za/topic/12146-sunsynk55-simple-local-data-monitoring-no-cloudinternet-needed-setup-guide-step-1-the-software/
  7. Like
    mojive reacted to Steve87 in How important is a earth spike on a solar installation   
    This document inspection summary may help some folks especially when they are getting quotations. If your quotation does not have these items you may want to query with the installer if these items are in fact part of the installation. 
    The CoC these days looks like a lot of attention is paid to the AC integration mainly and this is correct. However, the devil's details are in these items: 
    It is just a summary of pages not the entire document but is an eye opener for quite a few forum members that already have their installations and to the dismay of many they find that they are not safe nor compliant.




  8. Like
    mojive reacted to Anonymous_Llopi in Pylontech 3000C and 3000   
    You need a RS232 to USB converter, the converters nomally have a male conector, so the cables you need to do will need a Female DB9 conector (that's how the conector is called, RS232 is the protocol), heres one:
    https://www.amazon.com/HL-340-Serial-Adapter-Support-Windows7/dp/B08QJNJP6P/ref=sr_1_55?dchild=1&keywords=rs232+to+usb&qid=1622562550&sr=8-55
     
    you only need 1 USB to RS232 converter (you can just change it when using the Bs or the Cs) but pylontech US3000B uses a diferent console port conector from US3000C so you actually need to make 2 different cables for each version
     
    US3000B uses RJ11 on the console port, which is the same used by telephone lines (you might have one lying arround)

     
    US3000C uses RJ45 on the console port, which is the same as the LAN cables used for cabled internet on PCs for example (you might also have one lying arround)

    So you will need to get that RS232 to USB converter, 2 DB9 female conectors, 1 RJ11 cable with all 4 cables (some don't come with all 4 cables), and 1 RJ45 cable (with all cables as well)
    I would get a multimeter on continuity test to test which cable is which
    mix the cables as showed above and tape up every cable with electrical tape
    I'm pretty sure you can buy the US3000B cable somewhere but they are very overpriced
    I haven't seen the US3000C cable premade though
    Yes the updates up there will work as long as you use the US3000B update for the US3000B and the US3000C update for the US3000C
    Cheers
     
  9. Like
    mojive reacted to Anonymous_Llopi in Pylontech US3000c   
    Thank you so much for this information, I have 3 US3000B bateries and bought another one, but instead of them sending me a B they sent me a C!!!
     
    I had a RJ11 to DB-9 Serial to usb going into a rapsberry pi for ICC Solar, and it wasn't a pleasant surprise to see that they changed the console port from rj11 to a rj45, even if the RJ11 fits It doesn't work on the C
     
    Then I had the idea of making the C battery a Slave (and just conect the RJ11 on the B Master) but that doesn't work because apparently the C has to be the master if you have any Bs
     
    Anyways I did the cable and it works perfectly with icc, here's a more visual thingy if you wanna make it and wherever your db-9 port is male or female:

  10. Like
    mojive reacted to Achmat in Just choose 1   
    I think you can ac couple the sunnyboy on the aux input of the SunSynk inverter for additional capacity. 
  11. Like
    mojive reacted to Achmat in Sunsynk 8kW   
    Yes it does but I'm ok with the BMS managing the individual batteries in the bank. 
    With CAN, the BMS now also limits charge and discharge rates based on SOC instead of the inverter controlling charge and discharge rates. 
    I have 3 x 3.5kw pylontech batteries so max charge and discharge rate the BMS sets 111A.
    In the screenshot you can see that the BMS is now limiting the charge current to only 22A as the battery is above 95%.


  12. Like
    mojive reacted to Coulomb in Axpert earthing issue.   
    I'd say you have one of the Axpert models that has the neutral-out to earth relay (or extra contact, really). This is a normally closed contact, so with the unit switched off, you'll read zero ohms, as you did. And when in battery mode, it's also going to be shorted. But in line (bypass) mode, the assumption is that the incoming neutral will already be earthed, and the earth to inverter-out-neutral is floating.
    With that in mind, the whole situation may become a lot less mysterious.
    The models with this neutral to earth "virtual relay" seem to be the ones that come with main firmware version 73.00.
    From this post:

  13. Like
    mojive reacted to ___ in Axpert earthing query   
    I remember that thread. It was a really long time ago :-)
    A quick bit of theory.
    1. In most homes earth and neutral will be connected together, that is "bonded". This is done in order to tie one end of the supply to ground potential, otherwise both ends might float several thousand volts "in the air". Bonding it means you know the one is at 0V and the other is at 230V. It also means that a single earth fault (a path between either conductor and earth, be it directly or through a person touching it) is enough to trip an RCD. Without the bond a single fault might go undetected.
    2. The earth conductor is only allowed to carry fault current, there must be no "operating" current on this conductor. The current flowing in this conductor will be very close to zero most of the time, but all installations has a tiny bit of standing leakage, be it through current leaking through the insulation, or EMI filters and such in modern installations.
    3. If you make a second bond somewhere in your installation, you create parallel paths from that point on, and it allows operating current to run on the earth wire from there. This is therefore not allowed. You should have one and exactly one earth/neutral bond in the system at all times.
    4. Most houses have either a TN-S or TN-C-S earthing system. TN is for Terra(earth) Neutral, which means neutral and earth is bonded. The S means the earth conductor is separate. The extra C indicates that it is combined up to a point, and then separate. For a TN-S system, the separate earth conductor runs all the way back to the transformer. For TN-C-S you might have two conductors running into the premises, and then there will be an earth spike and a bond where it enters the premises, and from that point on the earth conductor will be separate.
    5. Rules remain the same though, no extra bonds. Those make earth loops.
    Now we get to the nitty-gritty of what happens at the inverter.
    1. When the inverter is in bypass mode, the live and neutral on the output is directly connected to the live and neutral of the grid, and since that neutral is already bonded, you're done.
    2. When the inverter is in island/invert mode, it opens the switch that connects L and N to the grid, and your neutral becomes unbonded.
    3. One way to fix it is to bond earth and neutral on the inverter output (before the transfer switch, in other words inside the unit). This isn't done in the Axpert, and there is a reason for it.
    4. The transfer switch in the Axpert is not double-pole on both sides. It has a double-pole on the grid side, but only a single-pole on the inverter side. The neutral of the inverter is never disconnected. I believe this is one of the reasons it fails SANS regulations, you're supposed to switch both legs. Because neutral is never disconnected, an extra bond in this position will create a second Earth/Neutral bond whenever the inverter is in bypass. So you cannot fix it this way.
    5. In that old post you quoted, an easy way to get around it was quoted as simply bypassing the neutral switch on the grid side as well. This way the grid-side bond remains in place even when the inverter is in island mode. Of course this is also non-compliant, even if it does work.
    6. The way other inverters do it, and also the newer Axperts, is they create a second bond only while they are in island mode, and remove it just before going into bypass. This is literally a relay between earth and neutral that is closed when the inverter disconnects the grid.
    7. Axpert's do this by switching the "dry contact" relay inside. You are supposed to wire this to an external relay/contactor of a suitable rating to do the bonding. The bonding relay, in other words, is not built in.
    All of this depends on your earthing system actually being TN :-)
  14. Like
    mojive reacted to viper_za in Axpert 5KVA MKS inverter installation planning   
    Hi all
     
    Let me just start with that my field that I work in is IT and for this I'm just trying to get an understanding of how things will fit together.
    My goal is to get all the wiring and breakers etc installed before I get the electrician to do the main AC connections.
     
    I have already purchased my first string of panels 3x 300W ReneSola Virtus II and the inverter itself.
     
    First off my inverter will not be installed next to the current DB as this is located in my passage between 2 bedrooms.
    This will be installed +-10-15m away with the battery bank next to it.
    The DB will be split with the stove and geyser not going through the inverter.
     
    Can you please have a look at my wiring diagram just to confirm that I am indeed on the right track with my planning.

    You will see that I gave the existing Breakers and bus bars a grey background and the new ones a white one.
    My current DB only has a E/L that functions as a main and I will be installing a new Mains breaker to be able to supply the inverter with "clean" power.
     
    The thing I am really not 100% sure about is the neutral to earth bonding on the output side of the inverter.
    I am also not sure about what size the cables should be running to and from the input and output of the inverter into the house.
    The same goes for the earth cable size.
     
    Any suggestions are welcome.
    Thanks
    Thys
     
     
  15. Like
    mojive reacted to georgelza in Difference : SOL-I-AX-5P vs SOL-I-AX-5K   
    its from a Meter reseller...
    busy watching : 
    So ye, was thinking it combines feeds... to cary workload, now clear it only switches between feeds. very different from what i believed, was lead to believe.
    makes the sizing for the panels and batteries on day one very different.
    G
     
    hmmm, 
  16. Like
    mojive reacted to Shockin in Axpert settings for Pylontech batteries   
    HI Coulomb
    Which 5kva Axpert uses direct cable to let the bms call the shots? Will the Sol-I-ax-5p do it
  17. Like
    mojive reacted to DennisD in Neutral/Earth bonding relay Goodwe ES inverters   
    I had the same issue with another inverter brand.  The electrician then did the bond on neutral and earth (apparently this is common practice). According to the electrician it is illegal to have higher than 20v(If I can remember correctly) on the neutral. ( I am not an installer or electrician just sharing what happened during my installation)
    Have a look at this Goodwe installation video :  (take note at 03:10)
     
  18. Like
    mojive reacted to gooseberry in DC changeover switch   
    This article explains it better. It seems there is something like this and it's called a DC transfer switch.
    https://www.solarpowerworldonline.com/2016/03/using-a-direct-dc-transfer-solution-to-better-back-up-solar/
    I'm also told the Axpert can't be connected to the DB in any way, is that true? Would I need to install a separate charge controller?
  19. Like
    mojive reacted to Coulomb in Axpert Firmware 73.00   
    Firmware version 74.40 is available here; I believe that 74.40 is a later version of 74.10:
    https://powerforum.co.za/topic/431-axpert-back-to-grid-solar-voltages/?do=findComment&comment=62213
    It is known that 72.70 and 74.10 can parallel. So you could update your 72.60 model to 72.70; that should parallel with your 74.10 machine. You could if you wanted update your 74.10 to 74.40. It would be good to verify that 72.70 and 74.40 are compatible.
    [ Edit: WARNING: there is no way to revert back to 74.10. I believe that 72.70 and 74.30 do NOT parallel (see this post), so either they messed up 74.30, or maybe 74.40 won't parallel with 72.70 either. So this is risky, unless someone else can verify that it works. ]
    Or you could wait for patched firmware version 74.40e; it should be available (at least in beta form) soon. Then you could run patched 72.70e with patched 74.40e.
  20. Like
    mojive reacted to Garthvs in Axpert Firmware 73.00   
    Morning All
    Does anyone know of a link to the latest firmware for the Axpert 5kVA / PIP 4048 ?  I have spent a significant amount of time searching the Internet without success.
    I have 72.70 but would like to test a newer version.
    Garth
  21. Like
    mojive reacted to Rautenk in Starting my grid-tied solution to load shedding   
    @Rclegg,
    I think you have a few items to play with. 
    I would strongly recommend that once you have gone through the measurement campaign look at doing a Hybrid system. 
    The Axpert is nice and cheap and great for back-up, but as per the video once PV becomes involved it is a different story. What the Video does not cover is what happens at load shedding times. That Grid Tied shuts down and only the batteries provide power. Bloody waste in the day! Whereas a true Hybrid will still utilise the PV panels.
    Then, I am going to severely disagree with @plonkster on the battery choice. I would AVOID the 200Ah batteries if you want to go over 3kVA. Your Deep Cycle lead acids actually do not like giving high current. So lets say you have a 5kW/kVA system and you switch things on max. Then you need to deliver 100A+ at 48V, batteries just do not like it. Better to go for 8x105Ah to manage the current draw overall. Your batteries will thank you.
    But, then again, it is MUCH cheaper(lifetime) to go for lithium at 90% d.o.d than it is to go for 8x105Ah batteries at 30% d.o.d (for if you want it to last 5 years). You actually end up with a very small margin of difference if you compare the 2.4kWh pylon to 8x105Ah deep cycle. And with Lithium advance BMS systems you can actually buy one now and add a few later. quite impressive, this CANNOT be done with Lead Acids, except with expensive electronics (which is included in the Pylon/BYD/SolarMD packages).
    With a Hybrid configuration (GoodWe for example, just because I don't want to satisfy the blue guys and say Victron), you will be able to have dedicated back-up circuits (i.e. your plugs and lights) and then the hybrid function will allow you to utilise the PV component for your geyser, stove, etc. Only thing will be that geyser, stove, etc will be off during load shedding.
    So summary:
    1. Get you PEAK LOAD ( in kW) which you want to connect to your back-up system
    2. Use worst case energy usage(kWh) over 3 hours as your required back-up time. (But only estimate with back-up system)
    3. plonk got it right, always install a change over switch... you never know if the inverter might go bonkers. It happens, especially with the Axperts (clones)
    4. Second DB is advisable and depends who reads the regulations, required. Some inspectors insist that back-up systems be physically separate from main circuits. This is very open to interpretation. 
    5. If you go CoJ route then you will probably need someone to certify the system
    6. If you add panels later, then you need to make sure that you take into account the Combiner or DC distribution box. You need to have fuses (or DC Circuit breakers) and Surge Arrestors before going into the inverters.   
     
  22. Like
    mojive got a reaction from ___ in New Offgrid Solar Installation 2 * Axperts MKSII 5KW advice needed   
    Hi Guys,
    Thanks to one and all, and a special thanks to Plonkster for the earthing advice.
    The system is up and running at my friends farm and he is over the 🌞 moon. There is still no generator and the system is running only on Solar and batteries. Loads are being gradually added on and the inverters are still on about 25-30% load.
    We still have not sorted an alarm that buzzes non stop when the Sun goes down and there is no PV power.  When the PV disconnect is switched off/on manually the
    buzzing stops. Any ideas! changed the setting 22 from AON to AOF but this did not help.
     
  23. Thanks
    mojive reacted to ___ in New Offgrid Solar Installation 2 * Axperts MKSII 5KW advice needed   
    Forgot about this half. No. Never ground batteries unless the manufacturer explicitly says you should.
  24. Thanks
    mojive reacted to ___ in New Offgrid Solar Installation 2 * Axperts MKSII 5KW advice needed   
    Let's see if I can make this really simple.
    1. On the inverter output, put a permanent link between the earth and the neutral terminal (note for anyone finding this thread in the future: In the context of this answer you can do this on the inverter in question... but on some inverters you will blow things up if you do this).
    2. In the cable that comes from the Eskom transformer there will be a number of wires, possibly as much as 5 (earth, neutral, and three phases). Ignore all wires except the earth wire (the other wires will be disconnected when Eskom fetches their transformer). The earth wire is connected at the transformer to a buried earth spike/structure. Connect this earth wire to the combined earth/neutral terminals on the inverter.
    3. Also connect the case of the inverter to this earth.
    4. When Eskom fetches their transformer, make sure they leave the cable with your earth connection untouched.
    So basically it's a two step thing. Step 1 is to tie the neutral TERMINAL of the inverter to the earth TERMINAL of the inverter. This is the so called N-E bond. The second step is to actually earth the thing to an earth spike, and here you use the very good earth that is already there.
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