Came home to an interesting errorr message that had shutdown the inverter.

"Xformer Polarity" is likely what you saw.

What firmware version is the inverter running?  (OUT page -> Enter -> down 3x -> Diagnostic -> top 2 lines, which should be the same)

It's worth noting that I've put a lot of safeties on the AC input code due to potential severe issues--which has historically been somewhat tricky.  I've relaxed safeties on more recent firmware updates, finding that they were a bit too tight for their own good.  (Oftentimes, dirty power or glitches would result in Xformer Polarity or other errors.)

basically, if the phase between the input AC voltage and the drive direction is reversed, that's an error (as the synchronous FET drive in AC input mode will result in a deadshort through the low-side FETs -> this will cause FET failure, which is why it's an error).

Ideally, this error would only be triggered if the inverter was internally wired wrong.  But it seems to be a tad too sensitive on older firmwares...causing it to trip on power line glitches.

It is running Version 1.1r6

Mine would do this of the power flickered for a split second longer than it took to switch from ac in to ac out. 

I'd suggest updating to 1.2r1 (latest)...hopefully this will resolve the issue!

Same...try updating to the latest.  Several customers who could reliably reproduce "Xformer Polarity" or "Input Fault" errors have reported no further errors after updating to 1.2r1 (@notmario no GS inverter errors on any recent powerline recloser activity, right?)  Plus some new bells and whistles in there anyway...including a completely redesigned local server page (if you're coming from 1.1r6) 😉

<a contenteditable="false" data-ipshover="" data-ipshover-target="/profile/2-sid-genetry-solar/?do=hovercard" data-mentionid="2" href="/profile/2-sid-genetry-solar/" rel="">@Sid Genetry SolarCorrect. There have been quite a few recloser events with recent weather activity - the GS has handled the events just fine with a short blip. I have nearly 4MWh on the GS now.
Bear in mind that my issue was "low output voltage" - not reverse transformer.

My only gripe that remains is the blip causes all of my electronics to reset. Wonder if that could be resolved by "anticipating" the load by looking at the load while on passthru, then correlating that with a predefined curve for low-voltage AC side, instead of simply titrating up from 0.

For those who don't know what reclosers are - they are why when you have a power outage, you'll often get a few 1-5 second blips with the power coming on and off. They are circuit breakers that will attempt to "reclose" to "burn off" the short before finally giving up and staying open. My low voltage error was caused during the "burn off" timer, where the short is enough to drop the voltage below the GS's threshold.

To some extent yes...and to some extent no.

The biggest issue is that "slamming" a toroidal transformer onto line power (without a soft start)...can result in a big enough kick to literally trip a standard 15A circuit breaker.  (Done it myself multiple times...flip a power strip on with a transformer connected, and immediately trip a circuit breaker.)

So yes, it is in the plans to get seamless line-to-battery ATS transitions by doing basically what you suggested (although open-ended on the FETs instead of full-driven, otherwise it will blow the FETs out at the start of the ramp)...but the crucial difference is that this will be taking place while line power is still present.  It'll just smoothly throttle up until the input line current is zeroed out, then (theoretically) be able to transfer that throttle value directly over to the "normal inverter mode" throttle value and disconnect the input AC via the onboard relays.

When line power is already gone (as with a detected power outage), I don't think it'd be wise for inverter longevity to "slam" the voltage back up immediately--that transformer kick could very easily end up blowing the FETs out even with no load on the inverter.

Worth noting that the "desired inverter throttle" is affected far more by battery voltage than by loads.  And transformer temperature will figure quite significantly in that equation as well (due to the wire temperature coefficient).  To precisely identify the "desired throttle" will require some pretty extensive math on top of the inverter gathering runtime variables to determine the unique transformer and system parameters.

Oh yeah. I was sure there would be a lot more to it than just load - figured my simple phrasing would get the idea across. It wouldn't take much to get into the Goldilocks zone.

About power-loss recovery. I wonder how it is that so many simple inverters seem to handle this scenario so well. My Sigineer is LF and it kicks in fast enough to barely be noticeable - though the power is significantly lower...

We can definitely experiment around and tweak the code a bit...but I'd hate to get to the point of random inverter failure as a result of pushing things a bit too far.

Betcha the Sigineer has an E-core transformer in it--those things are SO lossy that there's almost no risk to slamming them into an AC power rail.

I agree.

Yeah, i'm pretty sure it has a square-shaped transformer of some kind. How ironic that inefficiency could be an asset for certain scenarios.

So let me try and understand here. Is the issue that it's risky to begin inverting right after an outage because of the magnetic field collapsing - potentially in opposition? I'm confused about why this is different than when the ATS opens.

On the other hand, an optional timer to restore-power would resolve the issue with power-protection faults. (where a power supply refuses to resume after a significant, but very short blip - usually occurs with electronics) Hold off for an additional 750ms and it would look more like a recloser event to the devices (to which engineers are more used to making their devices tolerant) and reduce the chance of faults that require manual intervention.

2 hours ago, NotMario said:

So let me try and understand here. Is the issue that it's risky to begin inverting right after an outage because of the magnetic field collapsing - potentially in opposition? I'm confused about why this is different than when the ATS opens.

The issue is the extremely low leakage when connecting a toroidal transformer to power...like I've mentioned before, if you just "click on" even a GS6 toroidal transformer secondary directly to the AC mains with a switch, many times it will instantly trip an upstream 15A circuit breaker.  (A circuit breaker, mind you, that won't trip with a circular saw's startup surge.)

The issue is that if the FETs encounter this, you might as well kiss 'em good-bye: they're going to blow up (if not get partially damaged, and cause a random failure down the road).

I am suspecting this may have to do with the position of the AC input phase upon immediate restart--in other words, that the breaker trips if you happen to "slam" the transformer directly onto the peak of the AC wave...and by deduction it should theoretically be fine if the transformer was connected at the zero crossing.  If that is the case, then theoretically it would be OK to directly start the transformer from a zero crossing to full amplitude.

Here's a 'scope shot I took of testing a PJ ASL4 "48v" transformer primary against an 8650DPM Juntek DC-DC bench supply:

<img alt="image.png.92b231f1dfb57a2d0bd0d911e6cfb391.png" class="ipsImage ipsImage_thumbnailed" data-fileid="2203" data-ratio="60.00" style="height:auto;" width="800" data-src="//content.invisioncic.com/g308908/monthly_2023_03/image.png.92b231f1dfb57a2d0bd0d911e6cfb391.png" src="/applications/core/interface/js/spacer.png" />

Yellow is voltage, purple is current (registered through a PJ "big" current sensor).

Notice that the transformer reaches basically a dead short (current flies through the roof, and voltage plummets back to zero) in less than 2mS when presented with a high dv/dt (i.e. slammed into a 55vDC supply!)  Conversely, an AC half-wave is 8.33mS--so you can easily see the issue here: if the transformer saturates due to whatever reason, you might as well say "bye bye FETs."  Especially on the GS12, where the transformer's 48v dead-short primary calculates out to MORE than 19,200A (and that's not a typo, either.  Yes, nineteen-thousand two-hundred amps.  FETs are only good for 8,000A if you try to use the 10uS "surge" rating!)

Especially in your case with a 24v inverter, it's possible that the "ramp up" is taking longer than expected due to the batteries' ESR (as a result of the higher amperage than with a 48v inverter).  I know it's going to be basically impossible to capture, but if you can get a shot of the "DVLT" 'scope screen on a recloser event, that would be highly valuable for visualizing exactly how long the inverter's actually taking to regain output voltage on a power loss event.

1 hour ago, pilgrimvalley said:

one ofthe GS inverter design flaws is the lack of a soft start / restart up and may even occur in a low battery situation

Says someone who doesn't even have a GS inverter.........

...auto-restart on battery UVP/OVP, overheat, and even from overload has been an available feature since the very first sold GS inverter.  Try finding those features on a PJ inverter.

1 hour ago, pilgrimvalley said:

if the inverter shuts down and all your food rots that would be bad....or your heat source dies do to a inverter malfunction in the frigid winter that would also be real bad

I'm assuming your PJ inverters are much better in these situations, no?

Honestly, the reason certain situations result in a shutdown error...is because they are intended to detect/protect against unit failure due to a serious problem or even an internal/external wiring fault.  You don't want to "auto restart" into such a fault--because to do so will eventually damage the inverter.
For example, if the transformer polarity is backwards, to drive the FETs into battery charge will result in instantly destroying the entire bank of FETs--because they'll literally be shorting out the AC line.

So I do realize that I've had some "trips" a bit too trigger happy.  And that's what further firmware modifications and updates are working to resolve.

i am observing the problems of the gs designs...

to avoid these problems....

sigineer has some stout units as multiple reviews have stated

i hope the new 30000 watt PowerJack LF PSW SP module AMG4 version with its new features will be good....still to be determined though...

i will hope you can cure your gs inverter from doing the things described above in the future and not continue to blow out all the mosfets on the gs12k....so then 2 of the inverters would not have to be bought to be a redundant failsafe inverter system...

the people in the forum are describing issues with the old 6k made from PowerJack manufacturing company...

but the 12k prototype is still being changed and needs to be a proven design...