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Apples to broccoli comparison. Besides what I mentioned being optional (I'm sure it has downsides, probably cost), comparing road legal cars with a supercar is... interesting.

I'll need evidence of "Top power at Top Voltage." Since so little capacity is at that part of the curve, It'd make sense to design around (as in avoid, not feature) it rather than use it.

I suspect theres inductance and capacitance enough that even if the motors can't handle the voltage, it can be "clipped" until the pack comes down. (Especially since fmu these are 3phase AC motors, the motor driver is already regulating voltage and current to produce whatever the optimal waveform is)

I'm interested in... why? What are you building that loading data from disk is so lopsided vs CPu load from compiling, or network load/latency(one 200ms of "is this the current git repo?" Is a heck of a lot of NVMe latency... and its going to be closer to 2s than 200ms)

It doesn't matter if it's true. And those spec sheets aren't what you'll find on amazon products. I looked at them, didn't see any mention of temperature. Also, stupid things use XT60 connectors. Not remotely appropriate for 150v DC.

Haha, touché- forgot the Pi5 only has a single lane.

The comment came out of knowing if the cable's a little dodgy the timing could be off- scrambling the PCIe signals (easier to just tape it off than look up if its supposed to matter and then tape it off anyway), and the fact my first HBA had the "QC pass" sticker prevent some lanes from connecting and the whole card was unresponsive as a result.

Are they actually extra? Or does the other cable simply route them over coax? Answer here is to grab a couple SFF-???? Breakout boards, a scope, and a signal generator.

Another thing to consider is isolating all but the first PCIe lane.

Likely a reference to the recent addition of sesame to the allergen disclosure legislation in the US, and the subsequent rampant over labeling.

Nobody seems to remember a bunch of companies receiving rather large fines for pulling known bull-crap "may contain sesame."

Open circuit voltage is _very much_ widely considered to be the maximum. If its not spec'd openly as " at temp X" then it's reasonable to expect it to be invariant.

"Voc 37v @ 25*C"

Vs

"Voc 37v"

Edit: Isc is the same- max current.

That's humanity in general. But yea- general guide says "add up your open circuit voltage and don't exceed that." If something fails because of the panel manages to get more than 1000W of solar flux, and is cold... it's the mfgr's problem.

I need to actually look up why the extra flux increases voltage. Maybe it really doesn't but just moves the MPP to a higher voltage by having more current.

MosFET's or IGBTs are likely what failed. And, capacitance is something you do not want on a string of PV.

DC starts getting really nasty to deal with somewhere between 36-52v, with 150v of panels not being something joe-blow should be able to buy on amazon. Designing these systems to be safe is difficult.

4.2v for 100% SoC (State of Charge, charging), settles down closer to 4v once charging stops (likely not exactly correct, just my rote memory). 80-90% of capacity/SoC is between 3.7-3.8v.

The remaining 10-20% is above 3.8 and below 3.70v. 4.2v is the max to ever intentionally apply to a cell, and 2.5v is the minimum anybody specs as end of discharge.

As such- the "nominal" voltage is 3.7v or 3.8v.

Possibilities for 3.3v cut off include: LEDs' combined forward Voltage, a BMS set to that voltage, high drain applications pulling the voltage below a lower (potentially much lower at 10C to 50C discharge) cutoff voltage.

These are, of course, for NMC lithium secondary/lithium ion cells. NOT LiFePO4/LFP/LTO/Na-ion.

Theres lots of FUD, but most lithium stories are Li-Po cells (cell phones, RAdio-Control, laptops). Of the Li-Po's- most of them are for RC usage without any inbuilt protection.

LiPo's are beat treated like they're ziplock baggies full of 100mL of gasoline. If you handle them, I suggest buying an Ash Pot- their double walls give you a chance of containing a flaming pack. Best to just do it outside though.