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ChristoSnake

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  1. Haha
    ChristoSnake got a reaction from Marius De Kock in Youda's off-grid LAB   
    Thanks for all the comments!
    Here's a graph plotting inverter load, battery & grid power during the same time.
    The spike in the middle (12:30 - 13:10) was a 2kW hot water element turning on (via Geyserwise timer) to give our evening bath water a temperature boost.  Smaller spikes due fridge/freezer motors, and base load mostly swimming pool pump and a few computers.
    I am not allowing AC charging, only PV.  The time and current based charge is set for <1 A for 60 minutes and <48.6 V, so it should not interfere.  I'll see what it does today with CC = CV, as reference, then try again with CC > CV tomorrow to see if I can reproduce the weird behaviour.
    se dangerous "iron" PS:
    PS: I notice a lot of comments about "ironing".  I presume that it refers to the dangerous action of applying extreme heat to non-wrinkling fabric for the purpose of prematurely aging the fibers so that you have an excuse to buy new clothes?  I'm glad to report that we do not own any of those evil devices and would never consider taking part in such unnatural rituals :-)
  2. Thanks
    ChristoSnake got a reaction from Clovie in ICC software ends inadvertently   
    I update my Raspberry Pi's operating system once a month and also reboot it every couple of days - these two steps ensures that ICC never gives any hassles.
    Step 1: Updating the RPi is done by executing the following two commands in a console (without the bullets!).  Type "Y" or "yes" as required:
    sudo apt update sudo apt full-upgrade You may (optionally) execute this after the update to clean the software repository & save space:
    sudo apt autoremove Reboot the RPi to load updated kernel (if any).
    Step 2: To automate a regular reboot, execute this command in a console:
    sudo crontab -e Insert this line at the bottom of the file to reboot your Raspberry Pi at 03:00 every third day:
    0 3 */3 * * /sbin/shutdown -r now The line above is interpreted from left to right in the following manner: minutes (from 0-59) hour (from 0-23) day of month (1-31) month (from 1-12) day of week (from 0-6, 0 = Sunday).  An asterisk means "every", and */3 means "every third".  Change the line according to your needs.
    Press Ctrl-O to save the file, then Ctrl-X to exit the editor. That's it, you're done 😋
     
  3. Like
    ChristoSnake reacted to racemymotor in ICC software ends inadvertently   
    I've had an infini 3KW Plus for 5 years and it performed flawlessly until the communication board stopped working. I took the board out and the sticky dust that had settled on it had corroded the tracks on the board. I was quoted just over 2K to replace the board and decided it was best to retire the unit and purchased a 4KW Super which was on special at a ridiculously low price, and still is if you search hard enough.
    I've read some horror stories about the 4KW Super on this forum but all seem to be when they connected in parallel as well as older units. My unit is setup as a single unit and was manufactured in September 2019 so I'm hoping to get at least 5 years out of it like I did with the 3KW Plus I had.
  4. Haha
    ChristoSnake got a reaction from Barezzi in Sunsynk 8kw Inverter   
    Nice setup, but you forgot to install the last row of 4 panels on the right-hand side of your roof
    I have nearly as many panels as you have, and in summer my batteries usually recharge before noon.  After that I use the spare energy to boost the water temps in the geyser.  And later in the day the famous Pretoria summer thunderstorms make sure that there's no more generation to be had!
    In winter the batteries take a tad much longer to recharge, but at least we are blessed with cloudless weather so it does not really matter...
  5. Haha
    ChristoSnake got a reaction from Muchachos in SSEG commissioning letter   
    I thought about it at some stage, but seeing how well they hide the relevant documentation I came to the conclusion that they do not want anybody doing this 😋
  6. Like
    ChristoSnake got a reaction from Proxicon in Axpert VMIII Error 69   
    There's some good info on Lithium battery degradation available at https://batterytestcentre.com.au.  Here's their Pylontech US2000 testing over the past 3 years:

  7. Like
    ChristoSnake got a reaction from PaulF007 in OpenHAB   
    Cloud access and Android client!
  8. Like
    ChristoSnake got a reaction from tonio in Axpert VMIII Error 69   
    There's some good info on Lithium battery degradation available at https://batterytestcentre.com.au.  Here's their Pylontech US2000 testing over the past 3 years:

  9. Thanks
    ChristoSnake got a reaction from JK844 in What does your 5kva inverter power?   
    I also run my whole house off a single 5kW inverter:
    Borehole pump Swimming pool motor Oven & hob Geyser element Kettle Wall plugs Lights Panel heaters etc. Some of them are very high draw items (I'm looking at you, you 3kW oven!) and you may need to ensure that you do not run them at the same time as other high draw items (kettle or geyser element).
    It also pays to spread the load...  Our home's base load is around 500 W (3x fridges/freezers, extensive alarm system, three desktop computers, fish tank, etc).  Every morning at 08:30 our automated sprinklers turn the borehole pump on (1.3kW) for 30 minutes.  When they're done at 09:00 the pool motor starts up (750W) and runs until 17:00.  If it's very cloudy the solar geyser's element (2kW) may kick in at 13:00 via a GeyserWise megafter to ensure that the water temperature is at least 65 deg C.  If my wife were to boil a kettle (another 2kW) during this time, my home automation (Nodered & Sonoff) would turn the pool pump off to ensure I stay below 5kW.
    If you buy a grid-tied inverter like mine you can get away with peaks over its rated output (it will just supplement the difference from the grid), but I try to remain off-grid as far as possible.
    Oh, and I agree that it won't hurt to chat to Paul at FCS when shopping for inverters!
  10. Haha
    ChristoSnake reacted to RikH in Difference between Infinsolar Models   
    Jij bent niet bang!
  11. Haha
    ChristoSnake got a reaction from RikH in Difference between Infinsolar Models   
    Hold your horses, sir! There are some forumites who will be mighty upset when Victron is mentioned in the same sentence as Infinisolar 🙂
    But it does explain why it handles spikes like this (me doing some old-school arc welding) without any apparent problems...

  12. Like
    ChristoSnake got a reaction from RikH in First Investment in Solar   
    Not sure about the question ether.  RikH and I have the same inverters, and here's my take on it...
    The two MPPTs on the inverter are rated at 5kW & 900V each for a total of 10kW.  I have two 4kW series strings (about 500V) so I presume they are fine.  The inverter itself can deliver 5kW at 220V and another 5kW at 48V, thereby fully utilising the 10kW of PV input.  I've heard that it's OK to exceed the maximum PV wattage rating as long as you remain within the maximum voltage limit, but I am not that guy.
    In grid-tied mode it can blend utility power if the load exceeds 5kW, but in off-grid mode the 5kW load load cannot be exceeded (as I learnt by welding during a load-shedding episode!).
    The battery charger is always limited to 5kW because of its 100A max rating - no grid blending is possible.
    Does that make sense?
  13. Like
    ChristoSnake got a reaction from Richard Mackay in First Investment in Solar   
    I agree with Richard's summary above!
    My system usually recharges the batteries by noon (red arrow).  After that I am wasting potential energy as indicated by the solar energy dropping (green graph) to support only the load requirement of my home (blue graph).  Therefore I use my Geyserwise timer to give the solar geyser a boost starting at 12:30 (black arrrow), and it turns off as soon as the geyser hits 65 deg C.
    If you run the heater element too early, you're bypassing the whole idea of a solar heating.  Let the sun do its thing, and assist in the afternoon if necessary.  A 65 C geyser in the afternoon equates to >50 C the next morning, even if there's no sun later in the day (as a result of highveld thunderstorms in the afternoon, etc.).  And trust me, 50 C is plenty hot for a bath or a shower.

    PS: In case you're wondering: the jagged little spikes in power consumption are fridge/freezer compressors, but mostly the 200W fish tank element that works a lot at night.  We'll probably get cold water fish once the last of the tropical fish die off 🙂
  14. Like
    ChristoSnake got a reaction from Cyon in beginner   
    I did some welding today whilst running the pool motor, washing machine and a few panel heaters.  I have a 5 kW hybrid inverter and it simply borrowed some electrickery from the grid to make up the difference.

  15. Like
    ChristoSnake got a reaction from francois in Settings Infinisolar 3-Phase 10 KW   
    Battery specs for the US2000:

    So you can safely discharge six of them at 150A and not exceed their recommended limit.  Or go higher if your inverter, battery cabling and fuses allow.
    "Off-grid 1" uses a relay to physically disconnect the grid completely and will only use a mix of pv & battery (no grid!) to supply the load.  When it's overcast & your batteries are flat you will lose electricity completely.
    "Grid-tie with backup II" mode syncs the inverter to the grid and allows you to blend pv, batteries and grid to supply the load.  Using "PV - Battery - Grid" priority means that available solar will prioritise the load and additional current will be used to recharge the batteries.  When you disable feed to the grid & AC charger in this mode, you are effectively running off-grid but retaining the grid as a safety net.  Sort of like having your cake and eating it 😀
  16. Like
    ChristoSnake got a reaction from francois in Settings Infinisolar 3-Phase 10 KW   
    Hi John!  We have very similar systems and use them in the same way, so I will gladly share my settings with you.
    I run my inverter in "Grid-tie with backup II" mode and use "PV - Battery - Grid" to supply load when PV is available.  I use 100A as max discharge in hybrid mode because that equates to 5kW (my inverter's upper limit) and I don't (usually) exceed that.  I don't export to grid and I don't use the AC charger either (I have enough solar capacity to cater for all but the worst weather, plus enough battery storage to survive an off-grid night without fully charged batteries as happened on July 28).
    My bulk & float charging is set to the same voltage because the BMS system inside the Pylontechs manage their own bulk and float cycles any way.  I use Pylontech's lower voltage limit (52.5V) for charging.  I've brought my maximum charge current down somewhat (to 70A) because it allows the inverter to run a lot cooler, whilst still recharging my batteries by noon.
    I run the following battery cut-off points.  I found that 48.4V equates to about 25-30% SoC given my base load.  I've selected a 0.5V lower limit for when the gird is unavailable in which case I asume (never had tit happen yet!) that the BMS in the batteries will decide when to stop the party:

    My base load at night drops to about 500W and in mid-winter (longer night) it runs the batteries down to about 40% SoC.  Here's a graph showing battery voltage vs. SoC over the past few days to give you an idea.  July 28 shows you how much the voltage can vary whilst charging/discharging during an overcast day (while SoC remains constant), and also how my 48.9V cut-off seems to be very tough to breach:

    Hope this helps!
  17. Like
    ChristoSnake got a reaction from francois in Infinisolar WatchPower Communication Problem   
    I also use SolarPower successfully with my InfiniSolar inverter...
     
  18. Like
    ChristoSnake got a reaction from Richard Mackay in beginner   
    I did some welding today whilst running the pool motor, washing machine and a few panel heaters.  I have a 5 kW hybrid inverter and it simply borrowed some electrickery from the grid to make up the difference.

  19. Like
    ChristoSnake reacted to francois in PV Output Team - Southern Africa   
    Nice system you have. Welcome onboard.
  20. Like
    ChristoSnake got a reaction from Barezzi in How does ICC calculate a Cycle ?   
    Who knows these things?
    Measurable things are that the Pylontech BMS dropped my battery pack's SoH from 99% to 98% when I hit 320 cycles, so I assume they will drop by another percentage point when I hit 480 cycles?  The BMS gradually keeps lowering their maximum capacity (in available Ah) as they age, so when fully charged ICC now reports that I have 102% of available capacity!  It seems mostly to affect the oldest battery, and I think this is pre-programmed behaviour from its BMS based on cycle count and may not reflect the actual performance of the pack in real life?

    I also moved the goalposts by adding additional batteries after starting off with just one at the beginning of last year, and the new ones have fewer cycles on them which affects the performance of the whole battery pack.  We've also optimised our power consumption at night by letting PCs go to standby much sooner, saving a large thermos flask with hot water for instead of boiling cold water each time, dropping the fish tank temperature by a degree or two, heating the house during the day and not at night during winter (we only use the gas fireplace at night), using electric blankets instead of heating the bedroom, etc.
    Any way - we are now as close to off-grid as one can get when running in grid-tied mode 😀
  21. Thanks
    ChristoSnake reacted to PaBz0r in Pylontech - 80% or 90% usable capacity?   
    I see a new test report is out:
    https://batterytestcentre.com.au/wp-content/uploads/2020/05/Battery-Testing-Report-8-April-2020.pdf
    At about 1600 cycles (4.5 years) having around 85% usable capacity left and seems to still be going strong while some of the other friends have died along the way. 
  22. Like
    ChristoSnake got a reaction from francois in How does ICC calculate a Cycle ?   
    Who knows these things?
    Measurable things are that the Pylontech BMS dropped my battery pack's SoH from 99% to 98% when I hit 320 cycles, so I assume they will drop by another percentage point when I hit 480 cycles?  The BMS gradually keeps lowering their maximum capacity (in available Ah) as they age, so when fully charged ICC now reports that I have 102% of available capacity!  It seems mostly to affect the oldest battery, and I think this is pre-programmed behaviour from its BMS based on cycle count and may not reflect the actual performance of the pack in real life?

    I also moved the goalposts by adding additional batteries after starting off with just one at the beginning of last year, and the new ones have fewer cycles on them which affects the performance of the whole battery pack.  We've also optimised our power consumption at night by letting PCs go to standby much sooner, saving a large thermos flask with hot water for instead of boiling cold water each time, dropping the fish tank temperature by a degree or two, heating the house during the day and not at night during winter (we only use the gas fireplace at night), using electric blankets instead of heating the bedroom, etc.
    Any way - we are now as close to off-grid as one can get when running in grid-tied mode 😀
  23. Like
    ChristoSnake got a reaction from francois in How does ICC calculate a Cycle ?   
    Yep - when you remove the battery's full capacity and then add it back again, it counts as a full cycle.  That means that 100x charge & discharge sessions of 1% each counts as a full cycle. Or 10x sessions of 10% charge/discharge each constitutes a full cycle.  You can mix it any way you want!
    Voltage vs SoC changes depending on whether the battery is being charged or discharged, and has very little in common with the actual SoC.  Here's a graph of the two overlaid to give you an idea.
    I charge mine to 52.5V, and they stay there once charged with the load running off solar. When the sun sets and they take over the load, their voltage drops to about 49.7V even though they are still at 100%. The voltage remains fairly constant until the SoC reaches 70%, after which they take another dip in voltage to 49.3V. From there they drop gradually to around 48.9V in my system, which corresponds to a 40% SoC in the mornings. Once solar takes over the voltage jumps to over 50V again as the charging starts. You can also see the typical "Pylontech plateau" at 89% SoC while the BMS does its cell balancing before the voltage takes a sharp increase to 52.5V again.  Some folks say this only happens with new batteries.  Mine have 350 cycles on them and still do that. The graphs will obviously differ depending one the amount of batteries you have and the load your put on them.  Fewer batteries means that each of them must supply a larger percentage of the total load, and therefore they'll take a bigger voltage knock.  More of them means they each have an easier life, meaning less of a voltage drop per battery.   No two systems will be exactly the same, but the principle stays the same...

  24. Thanks
    ChristoSnake got a reaction from wolfandy in How does ICC calculate a Cycle ?   
    Yep - when you remove the battery's full capacity and then add it back again, it counts as a full cycle.  That means that 100x charge & discharge sessions of 1% each counts as a full cycle. Or 10x sessions of 10% charge/discharge each constitutes a full cycle.  You can mix it any way you want!
    Voltage vs SoC changes depending on whether the battery is being charged or discharged, and has very little in common with the actual SoC.  Here's a graph of the two overlaid to give you an idea.
    I charge mine to 52.5V, and they stay there once charged with the load running off solar. When the sun sets and they take over the load, their voltage drops to about 49.7V even though they are still at 100%. The voltage remains fairly constant until the SoC reaches 70%, after which they take another dip in voltage to 49.3V. From there they drop gradually to around 48.9V in my system, which corresponds to a 40% SoC in the mornings. Once solar takes over the voltage jumps to over 50V again as the charging starts. You can also see the typical "Pylontech plateau" at 89% SoC while the BMS does its cell balancing before the voltage takes a sharp increase to 52.5V again.  Some folks say this only happens with new batteries.  Mine have 350 cycles on them and still do that. The graphs will obviously differ depending one the amount of batteries you have and the load your put on them.  Fewer batteries means that each of them must supply a larger percentage of the total load, and therefore they'll take a bigger voltage knock.  More of them means they each have an easier life, meaning less of a voltage drop per battery.   No two systems will be exactly the same, but the principle stays the same...

  25. Like
    ChristoSnake got a reaction from francois in How does ICC calculate a Cycle ?   
    One cycle is a full charge & discharge of the rated battery capacity.
    So, if you discharge it from 100% -> 50%, then recharge it from 50% to 100% it counts as half a cycle.  If you do this twice, you consume 1 cycle of battery life.  Discharging from 100% -> 20%, then recharging to 100% again counts a 0.8 cycle.  Quite simple, really 😀
    If you have a Pylontech battery and it communicates to your ICC Pi with a comms cable, ICC simply reads the cycle count from the battery management software and does not calculate anything.  Oh, and it also has nothing to do with voltages or current either.
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