Using battery power to go off the City's power grid

You can ground an inverter to any true ground point......like the third pin in your wall....There are some really old buildings that have no true ground....this is certainly not to code and probably illegal.  I lived in a building like that in Berkeley back in the 80s.....I had to put a clamp on the cold water pipe to ground my system.

Thanks.  So I can take a ground wire and stick it into the 3rd pin in an unused outlet on a power strip?  Are there good ground wire ends with a thick single plug for a secure connection into the 3rd pin?

Yup....just buy a good three prong plug and put a large guage wire (12 gauge is fine) into the third pin only.....plug it into your strip or the wall and.....attach the other end of the wire to the inverter.  Any hardware store will have the plug and sell house wire by the foot....stranded wire is way easier to work with.

@viber6 fyi- i use 2 agm 100wh batteries with my  24v powerbright pure sine wave inverter for a total of 2400wh. I have 2 of these outlet setup’s on both sides of my home.  Each outlet set up cost me less than $500.  Already had solar set up to feed both controllers. (I could easily expand to 4 batteries if more time is needed.)

As for grounding, I buy an inexpensive audio power audio cord on amazon that has plugs that can be removed and take all 3 wires and connect them to the ground only on the male plug.  Then on the female plug I replace it with a spade to use it as a ground only connection.  Works well for my DIY ground boxes as well.

Viber,

I never said the larger Giandel is better in any way than a smaller one. Show me where I said that? Do you just make stuff up? The larger one can do more current (which most people do not need) and will turn on its fan at higher power. No one has A/Bed inverters that I know of except my friend who said the Ecoflow Pro beat the Goal Zero Yeti 3000 and both where trounced big time by the 5000 watt Giandel. That is all I know. We are in new territory here.....this is why I suggested you or someone buy both the large and small Giandel, the Bluetti and have a comparison party. You could A/B cheaper heavy AGM batteries with LifePo4 batteries, as well.

NO ONE KNOWS ANYTHING. How many brands of power amp are there? They all sound different.....How many brands of inverters are there? They all sound different. I personally would go for the Giandel because my friend (who has an $80K super revealing tweako system using super modified Apogee speakers) is the one that tested the inverters......he has great ears.....even listens to symphonies.....and jazz and pop and opera and rock and oldies, etc. Has both super vinyl system using Lithuanian field coil cartridge and r to r DAC.......every part in his system selected for sound.....and a very good room.