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It appears that forum software recompresses already size optimized images into much larger images after forum URL watermark is added. For example I posted this optimized image of 21 kBytes that got turned into an image of 132 kBytes. Original 21 kB image file attached as .txt

No idea, never seen inside of one before.

I am thinking to leave both positive and negative floating in reference to ground and use isolation monitor instead. This way if I come in contact with one wire I will not feel any shock but isolation monitor should pick it up and shutoff power.

Non-isolated from AC. Low frequency 50Hz commutating half-bridge of DC-AC inverter stage connects N wire to positive internal HVDC rail and on alternate half cycle to negative rail. When it connects positive to neutral it causes PV- to become negatively biased in relation to ground by HVDC...

Is this some kind of electric co-op you got?

Without knowing voltage at that precise point in time when current is highest you cannot know for sure if that 33A peak reading is accurate. Lets say AC voltage sags to 100V at 33A. Then at 120V peak current will be 120/(100/33)=39.6A There may be significant voltage drop in the house wiring...

If this was cheap 75/15 model same that I been using this way I would say yes. But since this is different more expensive MPPT I would take precaution with additional current limiting for first time turn on. That resistor is $3 (plus heatsink) and pack of 20A fuses is $5 (plus fuse holder). Not...

Ok so minus US$0.27/w incentives the cost is US$0.89/w installed. Equipment cost should be around $0.5/w leaving $0.39/w for gross profit or $2340. I guess if a crew of 3 does the install in 8 hours thats $768 labor or ~$1000 with overhead leaving $1340 for net profit. How much are engineering...

Nope, none of them are designed to fully protect power electronics and that's why inverters still blow up from direct strikes. MOV based SPDs are good for protecting dumb electrical equipment like motors and transformers from insulation breakdown. Much tighter voltage surge clamping is needed...

Its $40. But here is idea fop OP to use tankless water heater instead of tank. Just make sure to wire PV direct to heaters bypassing temp switches.

Fusing does not make them safe. Think of all those Tesla fires.

Toyota Prius has 20kW synchronous boost converter to step up 200V battery to ~500V for motor inverter. I modeled boost (and buck) converter in PowerEsim and got around 98.5% efficiency with SiC mosfet and diode after fine tuning inductor selection. I would not do 15kW in a single power stage...

You are forgetting Tesla.

Thank you. Can you show cycle life test and expected calendar aging data?

Owner will repanel and insurance will cover the cost. Good time to do it since panels are cheap now. May not be the case next year.

I would also bond solar panel frames together and connect them directly to ground rod via dedicated #6 solid copper direct ground wire. Also connect shipping container to same ground rod via it's own wire for redundancy. This way if your solar panel frame gets struck by lightning it will route...

This part (14m44s) for all those "no cell compression needed" people.

Hmm, that sounds like a misconception. Grid operator already maintains adequate reserve to feed peak demand in the evening when solar goes away while cooling load is highest. The grid would not collapse without rooftop or utility PV. The only value PV produces is preventing some natural gas from...

What? For weight ballast surface mount or earth embedded?

I found this cheap soft starter for $103. You can find even cheaper on Aliexpress.

That's normal. More likely it's your BMS disconnecting under high charging current. What do you have your bulk charging volts set to? Closed loop BMS comms or user mode?

I suggest using multiple 2.5kw boost converters instead of single 15kw buck.

Do you have a picture before damage?

I don't care how fast EMP is if your wires have inductance.

Wouldn't they just freewheel and passively rectify incoming AC into DC and charge DC bus capacitors? The IGBT body diodes in inverter H-bridge look like they form a bridge rectifier.

Use 12V LFP battery to power your amps. Continuously charge that battery via Victron MPPT fed from 24V system. I use this technique to run my 12V computer equipment from my 48V pack using Victron smart solar 75/15 as a charger.

At 0m56s you say that you had NG bonding screw in one LV6548 and there was no problem. Does your 6500ex have bonding screw installed? I watched your videos and it seems you could have an appliance pulling return current via ground wire instead of neutral which creates voltage difference between...

Yea I think the shock was superficial due to capacitive coupling between components. Inverters were ungrounded and floating.

If they are rated at 48V then they will be fine at 58V max 16S LFP battery voltage. There is no way they would rate them without at least 2x arcing voltage safety margin. A company will say that for liability reasons. Besides, if these are meant to be used with lead acid 48V nominal system then...

Can you find model number of relay used in your inverter? The data sheet should provide actuation lifetime. My guess it at least 1M cycles if done during zero crossing of AC waveform.