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P1000

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Everything posted by P1000

  1. It happens. Looks like you probably have to send it in...
  2. They get generated the same way as recharge vouchers, so you probably won't find any that will work with your meter...
  3. Get one of these: https://signaturesolar.com/eg4-chargeverter-battery-charger-48v-100a-5120w-output-240/120v-input
  4. It sounds like your inverter is outputting DC at times. A surge arrestor won't protect you from that.
  5. The harmonics come from the high frequency slope you introduce when you switch on the element mid-wave. Think of it in the frequency domain.
  6. Yes, and their other switching losses are also much higher. But perhaps I should clarify a bit more. Modern IGBTs don't always require negative bias to reliably turn them off, but in the output stage of an inverter, you can get noise/spikes coupling through the miller capacitance that can turn them on again. So in that case you want to drive the gate negative (you probably would do that for a MOSFET in that application as well). Here we are talking about the output FETs of the battery BMS, so you don't expect that much noise, and it's also not a fast switching application (well not continuously switching). And lastly, it's a much lower voltage situation, so the coupling through the miller capacitance should also be much lower.
  7. N-channels are easier to manufacture -> cheaper. -5V is not needed, because it's not an IGBT.
  8. @JustinSchoeman Is correct on this. Many inverters warn against the use of phase angle devices like this in their documentation - in fact you can cause far more complicated issues than is covered here. Luckily most inverters handles these issues remarkably well, but in general phase angle triggering is a bad idea on this power level even if you are just on the grid.
  9. I don't think it's a requirement from SANS, as batteries are not indicated on the COC, but some suppliers require it for the battery warranty.
  10. It can only output 20A. Everything it reports above that (4600W at 230V) is internal losses. (the only exception is for periods shorter than 10s).
  11. No, it's not required. Adding a CT only changes the point at which reverse flow is stopped. Without it, only things connected to the output of the inverter will be powered by the inverter or solar. By adding a CT, you are able to also export power up to where the CT is installed. For example, if your geyser is not on the output of the inverter, by placing the CT before the geyser, will allow the inverter to know how much power it uses. With that knowledge, it can "export" just enough power to power the geyser, without exporting to the grid. (It does require the grid to be present)
  12. Look for high voltage panels and expect to pay a premuim. https://www.sustainable.co.za/collections/rigid-solar-panels/products/enersol-395hv-395w-high-voltage-solar-panel https://www.sustainable.co.za/collections/rigid-solar-panels/products/renewsys-prime-275w-high-voltage-solar-panel
  13. If there is a big difference in price, the cheaper one is probably not solid copper, which makes up the bulk of the cost. (Most likely copper clad aluminium.)
  14. That is the difference between silicon grease and silicone. Silicon grease will also eventually dry out because it's silicon particles of different sizes suspended in silicon oil (Polydimethylsiloxane/PDMS) that eventually evaporates at higher temperatures. Any silicon thermal grease should be acceptable, but I think the cheapest is if you can get some from a plumbing shop. https://za.rs-online.com/web/p/thermal-grease/2173835
  15. Yeah, I missed that part, that does not make sense...
  16. It seems that you might be conflating efficiency and power factor, they are not the same thing. To illustrate, here's a snippet from the first datasheet I found for single phase motors:
  17. Most likely it's just capacitive coupling between the cables and the conduit. Earth it and forget about it.
  18. Yeah, a pump/induction motor is usually rated for output power, so a 750W single phase pump usually uses around 1.1kW. It is also possible to overload a motor, but that will affect it's life. Luckily a borehole pump is well cooled (pun intended). 3 phase squirrel cage motors tend to be a bit more efficient, but it looks like the omnicalculator refers to "amperage" per phase.
  19. Yeah, the manual is confusing. Go with what's in the table.
  20. Seems like that inverter has level sensor inputs (from a pdf of a pump solar vfd that at least looks the same): My advice would be to get somebody qualified to use that to achieve what you want to achieve. Snippet from here: https://www.invt.com/uploads/file1/20230803/GD100-PV Series VFD Manual_V1.8.pdf
  21. This is very true. Sorry, that wasn't meant as a personal attack on you or your batteries. It was on their technical knowledge and claims for life expectancy of their product that would lead to dissatisfied customers down the line. NMC can be fine batteries - if you know and acknowledge their limitations. I would not recommend them simply because LiFePO is intrinsically much safer and usually has better cycle life (with some other tradeoffs that don't really matter to me, like discharge rates, operating temperature range and energy density). As an aside - the SOH reported by the PACE BMS is the same as the "Full Capacity(AH)" column in the log, divided by the design capacity. At entry 288 you can see it drop from 100 to 48 in less than 5 minutes, so it's not always a very accurate reflection of life left.
  22. I'm surprized they lasted this long. The mistakes in their setup of the BMS when they first launched combined with NMC cells and the fact that they rely on charging to 4.1V to try and extend the cell life to their claims. It was clear to me it would end with them not being able to honor warranty claims.
  23. Cell 1 going both OV and UV means that it is buggered. You can't balance that out.
  24. Yeah, that's nonsense. What I think they mean is that positive from one battery and negative from the other (to the inverter). But that is clearly not relevant according to the logs.
  25. The first line is the most recent entry, with the oldest at the bottom (entry 400). Cell 1 is already 560mV lower than the max. Later you can see that cell 1 also causes Cell overvolt protection to kick in, so that cell is definitely very sick. It looks like that is what causes cell 13 to also present problems later. It's also cell 1 that causes a capacity reset to 48Ah at line 288. BTW, I don't think this is the complete log, AFAIK most PACE configs hold 2000 entries, but this could very well be different on Hubble's firmware. But a healthy battery does not have this many log entries...

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