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80m band abruptly went dead coinciding with blue/green line spike representing GOES proton flux. I guess we got hit by CME particles and it energized the D layer to midday levels.

CME induces DC in long distance transmission lines saturating cores of AC transmission line transformers and damaging them if not disconnected. It won't affect your home PV wires since they are not long enough.

106F or 41C sounds normal. Fuses have to use thin metal conductor so it can melt in event of over current. That thin conductor will have higher resistance than your cables and will run hot.

It's offgrid, pump motor is DC brushless more efficient than induction motor. It also pumps slower than typical pool pumps (~600w vs 2400w) which lowers water velocity and reduces water friction losses. But overall it still produces clear pool water at fraction of energy usage. My friend runs...

Friend of mine got this pump 8 months ago. Replaced 10A 240V pump. Runs on 4x 230W panels in series. Energy savings have been ~300kWh/mo. Should have paid for itself by now.

Yes absolutely. I thought that's what you were going to use.

That one was meant for continuous operation in line with PV input to reduce short circuit current if things went wrong with MPPT, not as precharge resistor. You need to use 10 ohm resistor for precharge. Explains big spark you got. It passed ~450A on contact. Better than nothing but still too...

What value resistor?

I literally proven it does not matter in 1st post of this thread. I guess gut feelings are hard to shake off even when faced with contrary evidence.

There was another opposite direction path to another LTE cell on a grain elevator. Most people around there bought data limited cheaper plans. I was lucky to grab true unmetered unlimited plan right before they got discontinued. Was only $20/mo for 2 SIMs (phone and 4G modem).

Would have to design some form of VCO for clock oscillator to get that frequency shifting.

That's called HF start. It sends high voltage pulse (few kV) through the torch to start the arc without tip touching the work piece. Is activated by trigger button on the torch or using lift start function.

High frequency inverter switching squealing is barely noticeable over outdoor fan noise. They have sound insulating mat around compressor to attenuate it. Other noise was from water getting flung onto condenser coil by the fan. It's not bad either. Can't hear either of those indoor.

Phone not included. Deal breaker.

Come on Costco stop tempting me.

Unless you are listening to VLF nuclear submarine signals then 50 Hz should not be an issue. Ferrite chokes block RFI above 100kHz pretty well.

If your MPPT controller is designed by real analog hardware engineers then it will limit its maximum current in hardware way before the micro controller can react. But if mosfet gate driver is driven direct from PWM output of micro controller then you are at the mercy of software PWM regulation...

Here is RFI mitigation thread from a month ago.

More precisely it has to do with how DC bus is switched into grid neutral via low frequency H-bridge IGBTs. It causes PV terminals to be biased at 50hz by DC bus voltage in relation to neutral and earth ground. This is normal operation inherent in this non-isolated Voltronic type inverter...

Not from dendrites but from possible over compression of small area and damage to internal separator membrane causing a short. OPs previous cells leaked and that's a good clue. Contamination during manufacture could also be possible.

I meant to say as one cell catches fire it will set fire to adjacent cells due to heat generated.

How much short circuit current each bank can generate. I see the logic now with 3V. But assuming only 1 cell went short may not be what happened later into this event. As one cell goes short and gets hot then neighbor cells will do the same after some time. A cascading failure.

Why are you only assuming 3V drop? Take it all the way to zero. 52V/0.0058=8965A per bank.

LOL compared to PG&E craziness on the other coast I think we have it pretty good with FPL for now.

Right but as soon as you tick over $25 electric service amount that minimum base bill item should go away. So in effect this creates "use it or lose it" amount of kWh each month. In my case that threshold amount would be 134 kWh. kWh: 134 base $ 9.55 non-fuel $ 10.96 fuel $ 4.58...

Ok then why don't I see this $25 item on my bill? Found this on reddit:

That was from the link in my comment. I plugged numbers from my bill and got 101 kWh "use or lose". kWh: 101 base $ 9.55 non-fuel $ 8.26 fuel $ 3.45 serv. Tot $ 21.27 gs tax $ 0.55 fran fee $ 1.31 util tax $ 1.89 reg fee $ 0.02 tot $ 25.04

5x Bussman TPL-CR 400A 170VDC 100kA interrupt rated fuses for sale. $30 each free shipping continental USA. They appear unused except 2 that look like they were cleaned with some solvent and had their markings erased. I can test their internal resistance to compare it to marked fuses. The one on...

Notice how similar the circuit board looks compared to Growatt 5000es. Looks like they took that design and stripped out DC-AC inverter part.

Don't use ferrules on those kind of terminals.

Do your homework on your own. Then we wonder why we get clueless engineers in the workforce.

Yes those steel plates look 1/8" thick. They will be too elastic at that length and will not be able to spread 11 PSI compression force evenly across entire cell side. Leaving it the way it is now is fine as long as you don't care about corner cells which will act as force spreaders to remaining...

Ban

Thinking more about this. It may not be a good idea because concentrating total compression force on small center area could over compress that part of cell jellyroll and damage the cell. Compression needs to be uniform across entire cell jellyroll. To avoid modifying your 3D printed end plate...

Or 3D print a hump on that PLA template in the middle to force yellow plates into spring mode to transfer force to the middle. You could also bend them slightly into U shape.