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Everything posted by Coulomb

  1. Error or warning? If it's an error, it will display as F04. If in an error state, it likely won't do much, possibly including updating the SOC. There might be other problems (e.g battery cabling) that are causing the battery low warning or error. That sounds like the DSP firmware; there is also display firmware that talks directly to the BMS. It might be worth updating the display firmware, at least on the unit that connects to the battery.
  2. It's straight through for the Axpert King, and the VM III uses the same removable display, even with the same display firmware. So it's straight. Any ordinary LAN cable would do.
  3. Actually, on reading the documentation again, I no longer hold this theory. With the solar balance setting off, the PV output current should be limited to the value of the total charge current setting. Suppose that's 60 A; that means that you should be able to use up to 60 A of PV charge current (at the 50 V end, so around 3 kW) to support the loads. That's clearly not happening. What I now suspect is happening is what @hoohloc reported; the BMS is sending a "don't charge, don't discharge" command to the BMS, and it's obeying it. Mu suspicion is that the Pylontech BMS is using too high a maximum charge voltage, and that's allowing the battery voltage to exceed 54.0 V, which is the panic level. But I don't understand how the battery voltage is supposed to fall if it's not being discharged. In summary: it looks like the BMS is the root cause. Whether the inverter firmware should be slavishly following the BMS commands is another question.
  4. I don't have time to compare the Growatt and Axpert firmwares, unfortunately. So I don't have a feel for how similar the firmwares are. But a lot of your problems, like this one, sound very familiar. I take it that the new firmware didn't fix the problem. I'm hoping to demonstrate it on the Axpert King that is now installed at Weber's house, and hopefully track it down from there. IF we find the problem in the Axpert, and IF I find that the relevant part of the firmware is similar enough, it MIGHT be possible to patch the Growatt firmware to fix it. No promises. Though it sounds like it's fixed in the 5000TL HVM firmware. It would be interesting if you can get Growatt to fix it for their 3000TLs, making their product better than the Axperts it was presumably copied from. It sounds like the firmwares that are not using the solar power properly are using the solar power exclusively for battery charging. It's like firmware with a Solar Balance setting that is permanently off (or possibly intermittently off). Regardless of whether there is a menu setting and/or command to change that setting. The Axpert command for changing the "solar balance" setting is PSPB. So you could try sending a PSPB1 command (with appropriate CRC characters and carriage return, of course) to see if that helps for a while (until the value gets overwritten again, perhaps). Edit: I've gone off the Solar Power Balance setting theory. See this post. The value used by PSPB in the latest Axpert King firmware still gets passed to the Solar Charge Controller (a separate processor on 145 V max models). I don't see it used in the 450-500 V max PV voltage models. Does this ring true for Growatt models? Edit: please continue to use the @Coulomb mention facility in replies, as I tend to ignore posts with "Growatt" in the title otherwise.
  5. There are some partial schematic traces here: Partial schematic traces. There are also some simplified schematics in the various service manuals; check the files section of this forum. Edit: it's probably not the relay driver, it's more likely the whole power supply collapsing, either due to a fault in the power supply, or something is drawing too much current once the firmware progresses to a certain stage.
  6. I'm 99% sure that these are clones; the metalwork is too different from what we see with the genuine Axperts in any rebranding. But hopefully it will work well for you; it's a roll of the roulette wheel.
  7. That should be a picnic to wire up . Just noticing the picnic tables in the background...
  8. Thanks for the data; I stand corrected. A fairly unusual beast, I think. It must treat the battery port like another PV input, except reversible so the battery can be charged as well as discharged.
  9. I believe that it should. Reading the firmware, I see that the paralleled inverters share the BMS data amongst themselves, for example. I think some earlier King firmwares (both DSP and removable display) had problems with this though. So updating to the latest firmware (71.97 and 02.66 as I post) might help.
  10. My guess is that these were actually wired 4S4P, for a 48 V system. 16 x 12 = 192 V nominal; I've not heard of such an inverter battery voltage. [ Edit: but see next post. ] Please look up the specifications and tells us what the nominal battery voltage for the inverter is. I had a quick search, and could not immediately find it. I can't see how he has 7 12 V modules working in any sensible way. My understanding is that lithium modules can never be wired in series; the resultant voltage would exceed the ability of the silicon switches to safely disconnect the battery in case of a problem (e.g. one or a few individual cells over-voltage).
  11. That sounds like the Solar Balance parameter (which can't be changed by a setting in most firmwares) is inadvertently getting cleared. But in two King firmwares (71.92 and 71.97), the solar balance setting isn't used. The global variable is still there, and it can still get set by resetting to factory default settings, but it doesn't seem to affect solar power use. But perhaps the Synapse King is a clone, and uses some very old firmware, or firmware different from the Voltronic Kings.
  12. ? I don't know the Growatts, but I'd be surprised if they didn't allow powering loads with PV, so the PV won't get "switched off" when the batteries are full. ? Again, I don't know about Growatts but I'd be very surprised if they didn't taper the charge as the voltage setting is approached.
  13. You seem to have muffed up the above link. But there were enough clues to lead me to this post: Sorry, I know nothing about WiFi monitoring via the Voltronic Android app. Edit: I'm wondering if the EEPROM faults are due to clones, and/or are likely to lead to fault code 90 (error 90) in the future.
  14. I assume that these are for an Axpert inverter of some sort, not using a BMS cable. Pylontech batteries are 15S LFP. 53.2 V is 3.55 VPC; that's a lot more than 90% SOC. I'd use 51.8 V. You could float at 50.3 V. To have the inverter automatically cut off at about 20% SOC, you'd want setting 29 at 48 V. Unfortunately with unpatched firmware, that makes setting 12 effectively 50 V, which means your inverter will switch to utility powering the loads at about 90% SOC, because of the problem in FAQ #2. With an LFP flavour of patched firmware, the effective back to utility setting is 0.5 V above the cut-off voltage, or 48.5 V, or about 24% SOC (assuming light discharging). These inverters are not designed for frequent load shedding. If your inverter has a 145 V max solar charge controller, then you could run patched firmware; see what can I update firmware to. Yes, though you'll get a solar charge controller reset, meaning that the solar charging will stop for ~30 seconds, stay at 1 A for ~15 seconds, then ramp back up over another 30 seconds. If you want to get back to battery sooner, you could put setting 13 2 V higher than setting 12 permanently. I would not put the two settings any closer, or you could be switching to and from utility and battery modes every several minutes.
  15. I don't like the high voltage SCC models because they don't include insulation monitoring and are therefore unsafe. And therefore illegal to use in Australia, though I'm sure that there are plenty installed here. You also get less total charging current, in the admittedly rare case of combined utility and solar charging. There is also the hassle of leakage when panels are wet, sometimes triggering bus over-voltage errors and other problems. Plus the whole idea of half wave rectified AC superimposed on high voltage DC seems crude to me. But that's just subjective; most transformerless grid tie inverters are the same.
  16. Yes. But only the ones with the high voltage Solar Charge Controllers. Which is the majority of the models now (sadly, in my opinion). That certainly seems to be where the industry is going (high voltage strings). And only in SUB output priority (often called "mode"), as far as I know, but they can do it.
  17. Yes, I think they would have done better with an arrow and a plus sign near the middle of the arrow. That surely suggests conventional (positive to negative) current flow.
  18. Sorry, no. These symbols are for IF the SOURCE is connected to them. They will be exactly wrong for the load. That's how those symbols are supposed to work, and it's all explained in the PDF linked to by PowerUser. I note that you appear to have swapped terminals 5 and 7 between the first and second photos; in the last photo, you have the polarity correct. Think of the breaker as a small-value resistor. So there will be a voltage drop across it. The voltage drop will have the polarity as given by the symbols. The positive input to the inverter will have a slightly more negative voltage than the positive end of the panel string, so it gets a minus sign even though it's way more positive than the other end of the inverter. This confusion is why some jurisdictions have banned polarised breakers.
  19. I don't think so. This series has apparently only 250 VDC rating per unit, so all 4 units need to be in series to achieve the 1000 VDC rating written on the front. That's a little misleading, I'll agree. So this 4-way block is intended to be wired in series. In fact, it's not intended that any wires are connected at the bottom. It's not visible in the photo what is going on there. From the installation manual: Note how the bottom terminals are whited out. It appears to me that you are trying to use these to combine two strings of panels in parallel, is that right? Four PV inputs at the top, one pair at the bottom leading to the inverter? I can't see how this can be done with this device. If however it's just a 2 pole 1000 VDC isolator, then that's fine. You could wire it as per the right side of the above diagram, with the +3 terminal going to the negative side of the inverter, and the -5 terminal going to the positive side of the inverter. The load side always has the "wrong" polarity. If that's what you're trying to do, and the big red box is lightning protection on the panel side, then I think you have the 5 and 7 terminals swapped, so these breakers won't be operating correctly (the magnetic blowouts will make things worse rather than better). But I can't be certain where the wires are going.
  20. What type and size of battery? It sounds like maybe the battery voltage is sagging too much, so it bypasses to utility power. Also check any back to utility type settings. Make sure that the battery type setting agrees with the type of battery that you have.
  21. The Axpert MAX used by the OP, and other Voltronic Power models with high voltage Solar Charge Controllers, actually do this blending in SUB output priority mode. But they limit the amount of power pushed through from solar to that used by the grid and battery charging, so that none goes back into the AC-in port. Apart from occasional blips from imperfect control, which can be a problem for certain types of utility meter.
  22. With the USE (user) battery type setting, the charge rate does slow down as the battery voltage approaches the absorb/bulk setting voltage. This would be close to 90% SOC. So that part is much the same. The thing you don't get without a BMS cable is slowing the charge rate when a single cell or two go high voltage, or high temperature. Or the whole pack approaches 0°C. Or disconnecting the load when one or two cells go low voltage on discharge.
  23. Yes. In SUB output source priority, the missing 2 kW plus losses will be supplied from utility, and the rest from solar. That's my book understanding.
  24. Errr. 100 A @ 50 V is 5 kW. There are 7.2 x 3 = 21.6 kW of inverter there. It all depends on the loads.
  25. Yes. Either your battery or the wiring, including any fuses, isolators, etc. No, although lead acid batteries failing after about 2 years is sadly rather common.
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