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Everything posted by JustinSchoeman

  1. Correct. But one thing I forgot - you must check 'Use Timer' as well. If not checked, then battery is only used when grid is not available (and charging is according to the battery configuration pages only). No need to restart the inverter - settings are applied immediately.
  2. 1) Check 'Priority Load' - this will direct solar energy to first power the load, with any excess used to charge the battery. 2) Set time of use settings (you can make them all the same). Set SOC/V to your minimum acceptable battery charge. If battery charge is above this, additional load will come from batteries. When battery charge is lower than SOC, then load will be powered by grid. If you check 'Grid' for a time slot, then the battery will also charge to that SOC from grid in that time window.
  3. There are a number of BMSs which are compatible - but they are not generally sold on the DIY market. Mostly wholesale to manufacturers. The ones that are available separately tend to be ludicrously expensive. The 'cheapies' generally used on the DIY market are intended for electric bikes/scooters/other vehicles, so they don't really bother with inverter comms.
  4. There is a guy on the other forum who did something similar, except he heats the 'old' geyser with excess solar once his battery is charged. I am not sure how much ambient heating will get you, as geysers tend to be fairly well insulated.
  5. You can read *everything* from the inverter... I read and use, time, inverter output power, load output power, battery state of charge, battery current, pv voltage and pv power, and then have a big look up table to determine target temperature based on all of those. I did contemplate using proportional control (Google PV diverters). It would make life a bit easier, but I don't like the idea of putting such a large non-linear load on the inverter.
  6. I just use a bang-bang controller. If PV voltage is above 'x', turn on the geyser for 10 seconds. Check PV output and battery draw, then leave it on/turn it off based on time of day and geyser temp. This is the logic I use: https://github.com/justinschoeman/ModbusThermostat/blob/master/SunsynkController/config.h Has worked perfectly for me for the past 6 months.
  7. Ewww. That does not look like a DC rated isolator. If it is ever switched off under load, it will just arc until enough burns away to break the loop... Does not explain the heat though. Probably bad connections and/or too thin wire.
  8. It should be pure sine wave... Damaged output drivers or output filter could provide a really nasty waveform.
  9. Fridge motors are usually quite robust. Hard to cook them with start up/change over spikes. I would suspect a waveform issue on the inverter. Easy to test if you have the right equipment, impossible if you don't...
  10. I uploaded the modbus protocol document here: You will need to find a suitable modbus library for your platform to send the requests, and process the responses.
  11. How are you sending modbus requests? If the TX light is not blinking, then the request is not being sent.
  12. It can run without batteries, but: 1) it can not run in parallel 2) you should not connect anything to the load/gen inputs
  13. You should be able to use my Arduino project pretty much as-is. Grab your favorite Arduino + a CAN shield (MCP2515 based for direct compatibility) + a RS485 shield.
  14. The CT must be on the house's grid input (other side of the non-essential loads). With zero export enabled, the inverter will adjust its feed to the grid side to make the CT reading zero. So with the CT on the line feeding the non-essential loads, these loads will get zero current from the inverter.
  15. 125A charge for the 250A discharge BMS.
  16. MCP2515 connects via SPI, not serial. You can follow any of the howto's on the web for connecting it to the Arduino - you should be able to find one specific to the shield you have.
  17. Just uncheck 'microinverter' and 'smartload' (if any is checked), and check 'gen charge'. If it is an auto start generator, you can also check 'gen signal', and it will signal the generator to start under the set conditions. (NOTE: gen signal and island mode signal use the same ATS port, so you can't use auto-start generators if you are using the ATS port for an earth-neutral bonding relay.)
  18. The Sunsynk inverter can supply power to all three AC ports on the inverter: 1) It can supply excess power (power not required for battery charging and load connection) to the grid port for powering non-essential items on the grid side of the inverter, and/or selling unused power back to the utility. 2) It powers the load port from solar/battery/grid as required 3) The gen port can be configured as 'SmartLoad', in which case the inverter sends power to this port according to configured rules.
  19. It should not really matter what order you turn things off. Personally, I usually turn off grid first, then inverter (green push button on the side), then PV (black switch on the side), then battery. Turning on, I do battery first, then turn inverter on, and wait for it to finish its power on process (about 1 minute), then turn on grid and PV.
  20. You are confusing issues. 18650 is a packaging. Cells are generally packaged in one of 3 formats: 1) cylindrical (of which 18650 is a specific type of cylindrical packaging) 2) pouch 3) prism Inside that packaging is a cell with a specific chemistry. Popular chemistries are: a) Lithium Ion (Li Ion) b) Lithium Polymer (LiPo) c) Lithium Nanophosphate (LiFe) d) Lithium Titanate (LTO) Generally, you can get any cell chemistry in any package type. Individual cells seldom have any built in protection circuitry, except when they are specifically
  21. 18650/pouch is just the shape. I am referring to battery chemistry. If it is a 3.7V cell, then it is some sort of LiPo chemistry, which can suffer from thermal runaway if not well monitored. Unless you know what you are doing, stick to 3.2V cells (LiFe chemistry) for DIY packs - or do a lot more research.
  22. Unfortunately, it would be difficult to tell from pictures. It would need to go for a 3rd party evaluation if this goes to arbitration or a court case. I would challenge them to: 1) indicate exactly which requirements in the installation manual you violated, and 2) provide written proof, preferably from an independent 3rd party, that the failure was caused by an external power surge.
  23. I would be very weary of using LiPo cells at all, never mind potentially mismatched cells in a large pack. The thermal characteristics of LiPo cells can result in a single cell 'stealing' all the charge and overheating. If you can't individually monitor cell temperatures (or at least clusters of adjacent cells), you will never know until it goes boom...
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