I got three new GFCI outlets.
One Hubbell (commercial grade), one Pass and Seymour (hospital grade), one Leviton (home grade).
They all work with the test button.
The Hubbell I like a lot, will put that in the boat. Seems to be nice quality.
The P & S had a slight buzz with the MSW, which I did not like. First GFCI I got that ever made a buzz on an MSW inverter, I was not impressed.
The Leviton seems cheap feeling, that I put in the bath, the P and S out on the back deck.

My test was simply to find out if a short to ground through a GFCI would save a MSW inverter from blowing up, that was my entire intention. Actually I think a short with resistance will be ok tripping the GFCI as I had tested that, but a hard serious low resistance short will cause damage even with a GFCI. I dont know why people want to make fun of finding out stuff.
My test was with a schumacher 750 watt running off a 3 amp hour lawn mower start battery, so the available current flows were limited.

The links are good, thanks. I had seen the first one, the ABYC pdf I had not read that one.

 

My test was simply to find out if a short to ground through a GFCI would save a MSW inverter from blowing up, that was my entire intention

I understand that, but what you don't seem to understand is that GFCIs cannot reliably provide such protection! GFCIs, by design, feature triggering and interval characteristics applicable solely to electric shock mitigation! -- Protection of the inverter from output-to-chassis short is an entirely different problem! Your test may work many times -- until that juncture at which the short coincides with an 'unfavorable' output phase angle -- or until the cumulative damage to the MOSFETs 'catches up with them', or any number of equally unpredictable and uncontrollable conditions!

As I see it you have but two choices for adequate shock and inverter protection:

1) Best option: Purchase a proper inverter!!! (i.e. a unit so designed that output neutral is connected to the chassis, and, hence, 'equipment ground'.)

--OR--

2) Very good option: Immediately follow the inverter with isolation transformers... I can personally 'vouch' for PowerVar model ABC1600-11 (16 amps @120V i.e. a true 1920 watts [2715 VA]) --- I purchased my units *new* for less than $800 (USD) each... And 'the word around' is they can be had for even less than that!

Either way only pennies stand between your present "fool's paradise" and getting on with your life!

With helpful intent
HP

 

Well, I have an update on GFCI on the boat.
My Onan generator had a slight miss. I cleaned the plugs by burning with a torch, miss went away, then came back on same cylinder, still had a miss, so.
I reved it up and cleared the missing cylinder. Generator running good, but an electronic casualty!

I forgot the gen was powering the AC power lines on the boat, I had the switches set for gen and of course I was testing the gens output. See stupid me, but I need robust equipment that can take a hit and still keep on functioning, not some wimpy electronic stuff that seems designed to fail and so sell more products.
A QO breaker GFCI burnt out, the type that goes in a breaker distribution box, not the outlet type. Normally a pricey part, it was a cheap used older 20 amp GFCI breaker, a good deal from Ebay.
Over revving the gen overvolted the output, so of course that particular QO GFCI breaker is so sensitive to power quality and not robustly designed, it can no longer reset, trips off immediately, it cant handle extra volts on the power line. I imagine a power line surge would have also wiped it's brains out. So dont buy QO GFCI breakers, not worth the money for what you get. I will drill out the rivets to see what is inside.

The commercial Hubbell outlet GFCI though is very robust, it still functions. It tripped but it also can still be reset and the test button works.
So I bought another commercial Hubbell gfci outlet to replace the IMO, cruddy poorly designed cant take a power line surge QO GFCI breaker in the box and just put the original robust QO standard breaker back into the distribution panel. That QO GFCI breaker has been redesigned, but who knows how robust the newer ones are.

So I have an older Leviton with those red and black buttons on the inverter output that continues to work and the Hubbell works protecting all the outlets.
(I run the inverter output to the entire boats electric system through a single 20 amp GFCI Leviton older outlet. It runs silent and has been working well. )

GF20L are apparently good GFCI outlets.
http://www.hubbellcatalog.com/wiring/section-h-datasheet.asp?FAM=Ground_Fault&PN=GF20L

I think on all those bad GFCI outlets experiences I have had fail over the years, likely power line surges killed them.

 

I'll give you this @sdowney717 --- Home distribution equipment surviving your 'stress tests' has GOTTA be good!

Best regards
HP