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There is some misunderstanding of basic V=IR here. Here is a fun experiment for you, Daisy chain 6 little alkaline 9v batteries and touch the 54v, !Side note, never short a voltage from one hand to the other, even if you think you are sure the voltage is low enough to be safe. Touch both + and...

Math is fun :D So 32 liters of water can handle something like 300 Mega joules of energy. I want to stay under 300c, starting point is 25c, specific heat of sand is 830J/kg*c So solving for kg I would need 1300kg of sand to match the water, But realistically only need absorb about 100 MJ, So...

The reason they use a ton of water when an EV catches on fire is because they don't have a giant steel drum they can fill up with water and throw the car into :D The firefighters are actually trying to achieve what I'm describing here. keeping the batteries in constant contact with water so...

Thanks, at some point I mixed up gallons and litters... I'd say I'm an idiot, but I'm pretty NASA crashed a spaceship due to a similar problem :D

Weird to think about the fact that we use water to put out fires, When water is built from 2 elements that burn like crazy together.

Figured it was pretty self explanatory, but these are 3.6v ncr cells.

Well the news articles that pop up from time to time about Teslas going up in flames, despite cell level fuses a good BMS and active cooling. Make me think that my extraordinary measures could be useful. At the very least for peace of mind.

Some panels give you NOCT which is a more realistic rating.

It's a problem in the sense that the pack will be ruined if I have a fire that is extinguished by this system. Which isn't a problem. Now if I have a leak that ruins the pack, that is a problem. But as far as making the problem worse, not at all. My 48V potential points can stay 1 inch apart...

Any thoughts on something like this: 15kwh 14s 18650 battery pack, Put it at the bottom of a 55 gallon steel drum put a couple 32 packs of water bottles inside the barrel above the batteries. Cut a hole in the lid and install a cooling fan. If all the other safety measures failed for some...

I might have missed it, where are you in the world?

Even if they didn't melt, boiling water would expand until the water bottles exploded, same result. And ya If I have 1200 lithium batteries on fire, I'm not going to be worried about melting a little extra plastic lol. Leaking is definitely a concern, I know those 1 gallon "milk jug" bottles...

What is so great about sand? Sand would just get hotter and hotter until the wood in my garage reaches 300c and ignites. The beauty of water is the phase change, it takes a huge amount of energy to boil water. And until that water is boiled away, the whole barrel is going to be sitting at 100c...

The main thing I was worried about losing is SOC, which isn't super accurate anyway (using SA virtual bms). I'm going to look into connecting my Batrium to solar assistant for SOC instead.

I have a couple Eaton HFD2125 125A breakers but can't find the datasheet. Does anyone know if polarity matters on this style of breaker? Like should my battery (+) be connected to the top or the bottom of the breaker? I vaguely recall reading that these big breakers have a magnet to force the...

I say no precharge, but I always power up the inverters from the grid first and then connect the batteries. Assuming it's not a bad reading the growatt says the battery is sitting in the low 40v's after powered on without a battery. I should check that with a DMM the next time I'm down for...

Trying to understand... please bear with me. Ok so ignoring ground for now. L1 is 110v to grid neutral and L2 is 130v to grid neutral. The inverter and autotransformer only see 240v (or less if the utility is out of phase) How would it try to balance the grid side when the neutral's are...

But you shouldn't connect your transformer neutral to utility neutral like he has in his drawing. Still watching... Ya that whole section at 1 min makes no sense. You have a single ground, and 2 separate neutrals and have no problems. Utility Neutral is connected to GND, Transformer Neutral is not.

Not sure if my expectations were too high, but every cell is 3.345 to 3.350 (yes my meter is calibrated) And yes I have double checked the crimps on the balance wires, they are solid. (even though in my head this shouldn't matter w/ balancing turned off?) Concerned about the 58mv difference...

Right I'm suggesting you don't bond the transformer neutral to ground. Is there something wrong with that?

Was thinking about this on the way to work today... I think a setup like this gives you reasonably good protection from a floating neutral with a 240v inverter? No flipping / tripping of a breaker results in a floating neutral. (tripping the transformer breaker cuts all power to the load...

Maybe I just missed it when all the other Growatt safety stuff was going down last month, But I just noticed something I wasn't expecting with my Growatt ES 5000(USA) I believe this is an artifact of originally being an EU design. Both the Solar panel + and - inputs are connected directly to...

Side question, the external power input doesn't need to be isolated does it? Like I can just wire a 5.5*2.1 barrel jack to my battery + and battery - ? (battery max voltage is under 58.4v)

My understanding is in the USA you only have 1 panel in a house with a ground - neutral bond. All other panels must keep gnd and neutral separate for the ground to work. This is done for the sake of the gnd, not the neutral.

Right I'm aware of the current calibration, I'm asking if anyone has figured out how to calibrate the voltage, (which isn't in the manual)

It’s possible to pass AC without shorting DC, just takes a capacitor. And it’s highly likely to design a dc solar input with a capacitor across + and - if you think about it. If you have one, all I did was measure AC voltage from the inverter case(earth gnd) to solar + and solar -, both show...

I'm pretty sure STC temp is actually the Cell temperature not ambient temp, So in the real world it basically never happens. It may be cooler outside of summer, but it's cooler because you are getting less sunlight, so still not going to hit stc.

Switched to external power, cell 16 is now showing the correct voltage, but Cell 7 and 12 are still wrong.

I have 3 Growatt 5000ES's hooked up to Solar Assistant currently, Just added an SC48120-MPV and wondering if it can be added? I saw someone talk about hooking it up to solar assistant, but not having any luck. There is no option for the Growatt SC's in Solar Assistant, Also tried connecting the...