P1000

https://za.rs-online.com/web/p/din-rail-power-supplies/1757776/

I saw that. It is very strange wording - I think as long as you stay well below 3A, you should be fine. A raspberry pi 2 should not be a problem, but the option in the post above is better.

https://www.communica.co.za/products/bmt-adj-dc-dc-module-3a-4-5-60v

Q2 Old battery 1 in parallel with new battery 1, old battery 2 parallel with new battery 2. This should be the simplest. Q2+Q3: 2 Batteries in series = voltage * 2 2 Batteries in parallel = Ah * 2 Wh = voltage*Ah <- if you double the amount of batteries, you can only double Wh, which means you can only double one of the variables on the other side. That way the physics lawyers won't sue you.

Look for a LM2596HV module https://www.aliexpress.com/item/32270826168.html I have not seen the HV variant available locally, only the normal LM2596, which only goes up to 36V.

Fair enough, but we tested that. I did not know V-0-V inverter-generators are common, since it adds a little complexity.

Q1: Correct. (Ignoring losses, but it should be fine, you might be at 33% DoD if the inverter is 90% efficient) Q2: The best would be to add 2 more batteries of exactly the same type. Add them in the same arrangement as the other 2. Perhaps simplest is to put each of them in parallel with each of the other 2. Q3. I am not sure I understand this question. 5kva inverters are usually 48V, so the number of 12V batteries should be multiples of 4. The Ah rating of the batteries relate to the Wh available. Wattage is more-or-less independent of that. Q4: I believe that would be the instantaneous Watt reading. If it was that for 1 hour, that would mean you used 350Wh, since it was for 2 hours, that would equate to 750Wh. But that is assuming your consumption was constant during that time, which is unlikely.

He has already taken those measurements and others. It is not V0V. It is an inverter generator.

I am confused? That is not what he is doing. He has an inverter generator, he is not moving the center tap, there is none. He just used the bulb for testing, and bonded neutral to earth after testing - direct connection. I believe it only seemed to be a V0V generator due to the output filter, a floating ground and the measurements he took.

IMO it would be easiest to do 12V or 24V lighting as well.

You are most likely correct, omnipower have a lot of rebranded stuff. That said, being from china does not mean it is bad quality.

I do not think that he has a V0V generator.

Yup. Measuring 120V on each of the legs does not mean it is split phase, it is most likely just the output filter causing that measurement.

With an inverter generator, the "generator" part is actually an alternator - so there is no concept of center-tapped. It is the same as having an inverter connected to a battery, except in this case the battery is the alternator. You need to apply the same rules as for an inverter that you connect to the DB.

If you were running at 50-70%, that means you were using more than 1000W for 2 hours? The batteries must have been just about depleted? (total storage is 24*105Ah=2520Wh) If you want them to last, you should probably try and half that, or get more batteries.

Yes, you can have it bypassed under some conditions - like if you have solar AND the geyser element is <2kW. If it is bypassed and you don't meet the conditions, there are some very steep fines. (or pay a fee to be excluded) from here: https://www.citypower.co.za/customers/Pages/Geyser-Control.aspx

Ripple relays are in use all the time to shift demand - mine is active for big chunks of the day (arount 6h00-9h30 and 16h00-20h30). The chances of people noticing is very small.

I don't see why it cannot be accurate - since it is an integrated BMS/battery. Usually you will have a model of the battery - say that you know when it is new, from full to say 3V/cell is 30% DoD (values are for illustration only.), then you can directly measure capacity every time you go past 3V. There should be a couple of such calibrated points - the most accurate of which would be 100% DoD. You also know the cycle efficiency, so you can do the same while charging. Your model should also then adjust the table as the capacity changes - at new 30% might be 3V/cell, by the time it reaches 40Ah, it might be 2.8V/cell and so on. Of course, if you buy a battery from one supplier, and a BMS from another, everything gets a lot more fuzzy, but with a big supplier like pylontech it is possible to get very accurate. (And I am only speculating, I do not know how they actually calculate it.)

Common is the connection to neutral. I would not use a dimmer like that on a geyser, for the reason mentioned earlier in this thread: harmonics. An inverter is also not going to like chopped current at 15A.

I am pretty sure they just make sure they meet at least the legal limit, and then write the limit on the label. All of the manufacturers do that. You can still buy Class E geysers, though... On the topic of geyser timers and switching a geyser on and off: This subject I find somewhat difficult to explain to most people, but I will give it a bash. The most important thing to understand with a properly designed geyser is that the water inside is not always at a homogeneous temperature. This is due the laminar flow of the hot water from the element to the top of the geyser. This is also why the element(actually the thermostat) should be installed roughly in the middle of the geyser - so that you only need to heat half the water when the geyser is cold. Of course, the temperature will homogenize over a couple of hours, but let's say the geyser is at a low temperature and you switch on the geyser. Now the element heats water and the hottest water flows to the top of the geyser. The hot water outlet is also at the top of the geyser, so the water you use could be at a much higher temperature than the average temperature of the geyser. This means that if you can manage to heat exactly the amount of water you need and then switch off the geyser, you can eliminate most of the standing losses. That is also the reason why some solar installations seem to not work well - if you have a shower during the day, and the pump is not on some sort of delta temperature controller, it will mix the hot and cold water in the geyser so that all the water is at the same temperature.

Those numbers changed fairly recently, so I suspect they failed to update it. Class E geysers will have standing losses of around 2.5kWh per 24hours (if you're geyser is 4 years old, you'll have one of these). The newer Class B geysers are around half that. Lagging will add negligible thermal mass - so yes, it is worth insulating hot water pipes. Especially since a lot of the standing loss is through heat loss to the pipes, even when the water is not running.

I am guessing that even if that does happen with any well-known brand, claiming would be a real pain, and the pay-out would be proportional to the years left on the warranty (in this case 1/20 or 1/25 of the replacement cost). Similar to mattress warranties. (Who even wants to use the same mattress for 20 years?)

I see what you did there... 🤣

Yes, the force of the hail caused the class molecules to move, the same way your molecules move when you walk 😛. It is most likely due to the RTV used to fill the space between the PV cell and the glass as well as the backing. A solar panel is more like a laminate car windshield than a solid sheet of glass.

You can also use your laptop as APN to which the inverter connects, with internet connected to the laptop ethernet, and wireshark or fiddler to snoop on the data.