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Calvin

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  1. Like
    Calvin reacted to bobcov in The BYD Blade, A Lithium Love Story...   
    Youtube has dozens of videos of batteries being nailed and sawed, some even while continuing to provide power. This should come as no surprise or amazing revelation to anyone who has been in this field for any length of time.
  2. Thanks
    Calvin got a reaction from WinstonG in For Sale: Pylontech US2000 Batteries   
    You need to be a bit careful with Pylontech cycle count/SOH: there is a simple console command that resets it!
    There is a built-in BQ34z100 chip that also calculates and stores the cycle count and cannot (to my knowledge) be reset, but few know about it. You can use command socsh to read it - result is in hex.
    Note: the BQ34z100 data is correct on US2000 series, but not for US3000 (due to being scaled for a 50Ah battery).
  3. Thanks
    Calvin got a reaction from HennieL in Heating LiFePO4 batteries in Winter / Cooling in Summer   
    I do exactly the same as @HennieL even though I live in a more temperate climate (Stellenbosch). I use a box insulated with 50mm Isoboard and heated with 2 28W heating pads (Adjustable Heating Pad With Plug 28W | Shop Today. Get it Tomorrow! | takealot.com). In summer the box gets cooled with a small air conditioner when the batteries approach 30C. I always keep the cell temperatures between 20 and 30C.
    The motivation is simple: Pylontech's own research shows the huge impact of temperature on cycle life.



  4. Like
    Calvin got a reaction from Warlok in Pylontech State of Health and Capacity relation   
    On these Pylons SOH is a very crude, hard-coded estimate.
    For the first 1000 cycles: for each 100 completed cycles the SOH is decreased by 1%.
    Thereafter, for each 167 completed cycles the SOH is decreased by 1%.
    SOC is calculated based on Coulomb counting (from full) using the current SOH.
    The exception to this is when charging above 89%, or discharging below 11%, SOC is based on a lookup table using the lowest cell voltage. That is why, when charging, the SOC seems stuck at 89% and then suddenly shoots up.
    A further exception is that, when discharging, if any cell voltage gets into the values contained in the lookup table, the SOC reported for the pack is that value. This is why SOC will suddenly drop very quickly if there is a weak cell in the pack.
    I have the full set of voltages and corresponding SOC values available if anybody is interested.
  5. Like
    Calvin got a reaction from Scorp007 in Pylontech State of Health and Capacity relation   
    On these Pylons SOH is a very crude, hard-coded estimate.
    For the first 1000 cycles: for each 100 completed cycles the SOH is decreased by 1%.
    Thereafter, for each 167 completed cycles the SOH is decreased by 1%.
    SOC is calculated based on Coulomb counting (from full) using the current SOH.
    The exception to this is when charging above 89%, or discharging below 11%, SOC is based on a lookup table using the lowest cell voltage. That is why, when charging, the SOC seems stuck at 89% and then suddenly shoots up.
    A further exception is that, when discharging, if any cell voltage gets into the values contained in the lookup table, the SOC reported for the pack is that value. This is why SOC will suddenly drop very quickly if there is a weak cell in the pack.
    I have the full set of voltages and corresponding SOC values available if anybody is interested.
  6. Confused
    Calvin got a reaction from CobusK in Nation wide power outage   
    Please tell me that you are joking.
    If not, do you really think that it is a good idea to pollute this forum with far-right political conspiracy theories?
  7. Confused
    Calvin got a reaction from TimCam in Nation wide power outage   
    Please tell me that you are joking.
    If not, do you really think that it is a good idea to pollute this forum with far-right political conspiracy theories?
  8. Like
    Calvin got a reaction from JaseZA in Nation wide power outage   
    Please tell me that you are joking.
    If not, do you really think that it is a good idea to pollute this forum with far-right political conspiracy theories?
  9. Like
    Calvin got a reaction from JoeMobstarr28 in Nation wide power outage   
    Please tell me that you are joking.
    If not, do you really think that it is a good idea to pollute this forum with far-right political conspiracy theories?
  10. Like
    Calvin reacted to frivan in Approved Off Grid Inverters   
    I coupled a 48V charger to my solar system's battery. I now declare this system off grid and compliant to NRS097.
  11. Like
    The OP has a Sunsynk and batteries. That allows him to limit the power drawn from the generator. Not all inverters have that ability.
  12. Like
    Calvin reacted to Peter Topp in Storage of Generator Fuel in Containers   
    Hi
    I do not know if this is the correct place to post this topic.
    I purchased a 6Kw generator many years ago before I installed an 8Kw inverter. I bought two 20l metal jerry cans and three 25l treated(red) plastic petrol storage cans.
    The metal jerry cans sometimes leak at the seal of the spout. I have since 3D printed thicker seals and have no more problems. The metal cans can also rust as there is a small amount of water in the petrol and can separate when stored.
    A bigger problem was with the treated plastic containers. I filled the containers and sealed them for when needed. I had stored them for quite a long time and when it came to using the fuel this is what I found.
    The plastic caps on all the containers were broken (cracked) and needed to be replaced. After some thought, I came to this conclusion. The full cans were sealed in the winter when it was cool and when the weather heated up the pressure from the petrol heating up broke the caps. I also lost a lot of fuel through evaporation. I now store the petrol in the treated plastic can and slightly loosen the small breather cap on the opposite side of the spout.
    I know that you should not store petrol for more than a year and now fill my vehicle with the stored fuel after 6 months and put fresh fuel in the cans. I also do not fill all the cans.

  13. Like
    Calvin reacted to Stefan Cornelissen in Savings   
    https://www.hellopeter.com/infinity-group-companies
    Don't think I can trust them with my money
  14. Like
    Hi
    Recently after having a power failure with being rainy and overcast the previous day, I woke up to find my house without power despite having an 8Kw Sunsynk inverter with 500ah batteries.  It was 5:30 am so I took my torch and investigated only to find I had completely depleted my batteries.
    I had recently coupled my geyser to the grid from gas as I had added more PV panels and had ample power (9000w) to use. I also have to power a borehole pump and aux pump from the JoJo tank.
    I have a 6Kw petrol generator coupled to the inverter which can be switched to the grid or aux (gen) input without an auto-start. I proceeded to start the generator and switched the generator to the grid input, only to find that this did not work. I was very annoyed and then switched over to the aux (gen) input to find that this also did not work.
    I thought I had it all sorted when I installed my system and bragged about my installation, however to my regret, I got a wake-up call.
    After checking the generator voltage indicator, I saw it did not show any voltage. I was convinced that this was a generator fault and did not try to put the generator in the bypass mode. I proceeded to switch all the large loads off (borehole pump, switch the geyser to gas, and only use the gas hob). After taking my grandchildren to school the sun was up and my PV panels did power the house to my relief and not to get an earful from my wife.
    After getting help (4 guys) to remove the generator (100kg) from its bricked housing I started my fault-finding. To my surprise, only the mechanical voltmeter was broken.
     What now as it was not the generator?
    I took the time to clean the generator and put it back in place with help. I did all the switchovers again only to find it still did not work.
    Just to mention that I have spent more than 40 years working with electronics and instrumentation.
    One of the most important things I have learned over the years is to go back to read and follow the instructions. 
    This is what I did. I also followed up with videos from Sunsynk and this was the result.
    1.       The biggest problem was the frequency which was 54.6 hz.  I had to adjust the frequency on the generator under load as close to 50hz as possible. This can be done by adjusting the screw on the linkage arm of the carburetor which will correct the speed and frequency.
    2.       The frequency band on the inverter also needed to be adjusted for a larger band to accommodate the frequent load changes of the generator.
    3.       There are other settings as well that affect the inverter if the generator is grid-coupled or aux-coupled. It also matters if you use timed settings as this will override the start and stop charging settings of the battery. The grid-tied generator to the inverter is much less forgiving to frequency change.
    4.       The charging of the batteries from the generator needs to be set lower on a grid-tied generator.  if you set it too high there will be no power for the household load. The best Installation is to have a generator twice the power of the inverter so that it can charge the batteries without affecting the load. This is always not possible so be sure you have adjusted the settings for the size of the generator.
    5.       If you have an electrician do the installation, make sure that he has done all the checks and has tested it before it is signed off. It will always be up to the owner to read the instructions so you can be sure the electrician has done all the tests and correct settings or else when the generator is needed it might fail and you might need to pay again to have it set correctly.
    6.       Finally, the earthing of the generator.
    A.      If it is coupled in the grid mode, the neutral has to be coupled to the earth as there is no link to neutral for a series earth leakage (RCD) to work if the mains neutral is decoupled.
    B.      When the generator is coupled to the aux (gen) input the inverter should already have an earth bond relay installed to protect the system with the earth leakage (RCD) in series when the neutral is decoupled from the mains in the inverter during a power failure. I use an automotive 12vdc relay which can handle 30a.
    In a complete circuit, there must only be one earth-neutral bond.
    I see many installers fitting a permanent bond between earth and neutral on the inverter. This is illegal as now there are two earth-neural bonds when the mains power is present. (one in the inverter and one in the DB. Box).
    I find it pure laziness that an electrician cannot use a relay to couple the neutral to earth even if the inverter does not provide a signal or voltage output as he can use the 220vac mains power input to the inverter as the signal to connect the bond.
    NB: THE earth-neural bond must be the bond of the neutral on the output of the inverter to earth and not the neutral input from the Mains Power input.
     
    The earth-neutral bond done on the Mains input is only done when the Mains Power is disconnected (live and neutral) and a Generator is used as the Mains Power input.
    All is now good and working as it should.
    I hope this will help someone who wants to couple a generator to an inverter and avoid the same problems and frustrations I have gone through.

  15. Like
    Calvin reacted to GreenFields in Help me go off grid in winter   
    Wouldn't look a gift horse in the mouth. Just take the generator.
    Is this an off-grid inverter installation, or are you catering for a complete and utter collapse of Eskom? If so, then yes, by all means, hook up the generator and install additional panels, for the gloomy Cape weather.
    But what about if you are connected to the grid? Personal 2c worth, to each his own. In that case I'd say simply... do nothing. Considering the amount of battery power you have relative to your daily needs - between 1.7 to 2.5 times your daily consumption - I'd just run down to a 50% battery reserve for loadshedding, and otherwise once you reach that 50%, switch to grid.
    I just don't think the other options are worth it relatively speaking. Instead of running the generator at say R10 per kWh, you could just as well wait for loadshedding to be over and charge batteries from the grid.
    Also, you've already got enough panels connected to cater for normal sunny days and even partly cloudy days most of the time. The extra 2 panels, if it's 1kW of nameplate capacity you're adding, then during the worst weather they'd be generating maybe 20-30% of what they are rated for, and other parts of the year they'd be superfluous to your needs. For maybe, say 30 really miserable days a year that would be just 1-2 extra kWh roughly available on the bad days. Call it R100-R200 return on investment per year, very roughly thumbsucked. Again, may as well just ensure you keep some reserve battery capacity, and run and charge from grid around the loadshedding slots, than incur the cost of the panels for a meagre additional benefit.
  16. Like
    Calvin got a reaction from Chunks in Pylontech US3000 after 6yrs 🤪   
    I have some US2000, US2000C and US3000B. For all those, the SOH and cycle count are calculated with a simple formula (by the BMS)
    Cycle count goes up by 1 for every 50Ah discharged on US2000 (74Ah for US3000)
    SOH goes down by 1% for each 100 completed cycles.
    For a stack of Pylons the same logic applies - simply use total capacity and discharge.
    So, @Youda , your 8 x US3000B had a total of 3890 cycles on 30 Jan. Expect the SOH to drop to 95 any day now when the stack total gets to 4000 cycles.
    A note of caution: this is based on observations on my batteries, all of which have been treated very gently. They are all at about 700 cycles.
    I have one data point from an older US2000 that leads me to believe that the formula changes at 1000 cycles/90% SOH. The slope thereafter seems to be 0.6% SOH per 100 cycles (or 1% for each 166.7 cycles)- that will nicely get it to 60% at 6000 cycles that Pylon claims.
    The bad news from all of this: the Pylon's SOH is not an indication of how well the battery has been treated. It is simply an estimate of remaining capacity based purely on total cycles. This is very disappointing given that they have a very sophisticated chip (TI BQ34z100) in the BMS whose sole purpose is to accurately estimate SOH and SOC based on real measurements.

  17. Like
    Calvin got a reaction from Youda in Pylontech US3000 after 6yrs 🤪   
    I have some US2000, US2000C and US3000B. For all those, the SOH and cycle count are calculated with a simple formula (by the BMS)
    Cycle count goes up by 1 for every 50Ah discharged on US2000 (74Ah for US3000)
    SOH goes down by 1% for each 100 completed cycles.
    For a stack of Pylons the same logic applies - simply use total capacity and discharge.
    So, @Youda , your 8 x US3000B had a total of 3890 cycles on 30 Jan. Expect the SOH to drop to 95 any day now when the stack total gets to 4000 cycles.
    A note of caution: this is based on observations on my batteries, all of which have been treated very gently. They are all at about 700 cycles.
    I have one data point from an older US2000 that leads me to believe that the formula changes at 1000 cycles/90% SOH. The slope thereafter seems to be 0.6% SOH per 100 cycles (or 1% for each 166.7 cycles)- that will nicely get it to 60% at 6000 cycles that Pylon claims.
    The bad news from all of this: the Pylon's SOH is not an indication of how well the battery has been treated. It is simply an estimate of remaining capacity based purely on total cycles. This is very disappointing given that they have a very sophisticated chip (TI BQ34z100) in the BMS whose sole purpose is to accurately estimate SOH and SOC based on real measurements.

  18. Haha
    Calvin reacted to Sidewinder in Eskom Schedule of Standard Prices   
    Seems there is a paragraph missing:
    22. Homeflex penalties:
    The following penalties shall apply to each POD:
    1. Per month:
    1.1 A proportional penalty each and every time that Eskom fails to deliver Power at the POD.
    1.2 For each and every failure - forfeit the R/POD/day rate in totality.
    1.3 Pay additional penalties in relation to the Stage of Load Shedding: E.g. Stage 6 - applicable penalty is 6 x R/POD/day rate.
    1.4 Penalties may not be used to offset Usage at the POD.
    2. Per Year:
    2.1 Should the Utility fail to provide a 24 x 7 x 52 service at the POD, it will be incur additional penalties as follows:
    2.1.1 R10,000 if any failure occurs during this period.
    2.1.2 This amount is to compensate for long term effects of any loadshedding, e.g. replacement of electrical appliances, inconvenience, insurance premiums, additional expenses incurred at the POD by the home owner to ensure a continues supply of power.
    2.1.2 Penalties may not be used to offset Usage at the POD.
    3. No excuse performance will be tolerated. E.g. generation, distribution, force majure, Regional & National Government, etc.
  19. Like
    Calvin got a reaction from TRINITRON in Pylontech US3000 3.5kWh 48v Lithium-Ion Solar Battery   
    The label in the picture shows manufactured in 2020, but you still say age is 2 years?  A mistake I assume, as the US3000B was discontinued in 2021.
    Also, has it been topped up in the meantime?  Leaving a battery without charging for 5 years may well ruin the cells due to self-discharge...
  20. Like
    Calvin got a reaction from TRINITRON in 6 off Pylontech US3000C for sale   
    Pylons are notoriously sensitive to how well they are treated - you will make your life a lot easier selling these if you connect a PC to the console port and extract exact cycle data and logs via BatteryView.  That way people will know what they are buying, and you will be able to get a fair price.  Failing that, I suspect that potential buyers would assume the worst.
    2 other points:
    The picture you show is a US3000B, not a US3000C.  They are significantly different.
    These are now available brand new for R15k. Pylon US3000C 3.5kWh Li-Ion Solar Battery (excl. brackets)
     
  21. Like
    Keep the inverter in a cool and ventilated place.
    Also, protect it from collecting excessive amounts of dust.
    Do not put high inductive loads on it. (IE: do not put 5kVA motor on a 5kVA inverter)
    Follow installation instructions, especially when comes to proper grounding, SPDs, input voltages.
     
    IMHO, there's not much you can do proactively, if you don't want to crack the box open and replace one third of the components in advance. Which, to be honest, nullifies advantage of a cheap box.
  22. Like
    Calvin reacted to GreenFields in Can Solar Panels saves money is it true?   
    Be very careful with making this decision. Note below, that Nersa has reportedly now approved the restructuring of Eskom's tariffs into a fixed fee and time-of-use fees, with some other changes. You cannot base your decisions & payback calculations on the people that installed solar before you because the rules of the game have just changed, and we'll only see how the dice land from 1 July onwards.
    Nersa approves restructuring of Eskom tariffs - Moneyweb
    That being said, if you go about it smartly, know your needs, choose and use your system wisely, it's surely possible to drop your costs now and especially in the long run. If you just slap something in without proper analysis, you could also be wasting lots of money.
  23. Like
    Calvin got a reaction from Youda in Balancing Pylontech ?   
    It seems to me that both Pylontech and Voltronics are to blame.  Pylontech for requesting voltages that are too high (in the real world, where 2nd rate manufacturers implement poor control algorithms that overshoot) and Voltronics for being such a 2nd rate inverter manufacturer.
     
    You will probably find the other batteries are all in advanced stages of degradation.  Consider setting battery type to USE and max charge voltage to the lowest that still gets you to 100% - my Pylons work well at 52.6V.
    Also consider setting the float voltage down to about 50.5V.  It will mean that your SOC will drop to about 99.5% as soon as the batteries are full, but it will greatly enhance their lifespan.
    Of course using an Axpert means that your inverter cannot be relied on to correctly switch to float, unless you are running a version of @Coulomb's patched firmware.
  24. Like
    You may be able to do better than that: if you run the pwrsys command, the field "System RC" is the system remaining capacity and the field "System FCC" is the Full Charge Capacity.  The more accurate SOC is ((double)SystemRC * 100 / SystemFCC).  The reported SOC is that number, truncated to the integer.
    This applies to the whole stack irrespective of the number of batteries in it.
     
    Have you found a good source of load-shedding schedules, ideally via an API rather than scraping?  I am aware of https://loadshedding.eskom.co.za/LoadShedding/GetStatus but am looking for actual schedules.
     
    Nice system BTW.  And there I thought that I was a control freak... 😆
     
  25. Thanks
    Calvin reacted to Youda in Pylontech   
    Just a note for the curious:
    Ports A/CAN and B/RS485 on the US3000C are having both protocols in each port. So the A is technically CAN+RS485, B is CAN+RS485 too. Daisy chaining of multiple "piles" together runs over RS485 protocol, the conversion to CAN protocol is done by the LV-HUB in the last step. Daisy chaining of individual bricks within a single pile uses RS485 protocol too, but this time via LinkPort0 and 1 ports.  

     

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