powerjack power inverter 26,000 watt AMG version 48 volt PSW LF 13,000 watt continuous at 240 volts or 120 volts etc.

What @thebutcher said.  Appliance that use a diode as a cheap way to get a "low" setting, will wreck havoc on an inverter's regulation function in such modes.  In the case of a PJ, it will run the regulator into a wild oscillation--resulting in what you describe.

Thanks gents, that explains it perfectly. 
before I connect this to the house, any concerns with the split phase? The sine wave looks good at 240V,  But any concerns with one leg being slightly higher in voltage than the other. I suspect that won’t matter with my electric oven, but what about my ac? I do have a soft start on it, so I believe the inverter will start it

 I suspect that won’t matter with my electric oven, but what about my ac? I do have a soft start on it, so I believe the inverter will start it

Again  PJ engineer  do not know  US  split phase system .   If your transformer has 6 wires then it will not be good  for L1  N  L2  split phase .   Ebay  say not for L1  N  L2  also .

L1  and N  is 2  wires  then  L2 and N is 2 wires  .   That account for the 4  wires  but  there is 2 more wires  for what ?     If all your load  is 120vac then  ok  for split phase wired for the house .    240  load like  oven and water heater  may  cause  the rev 11.1  control  board to shut down and save the  FETs .     I  really  like to see more review  on the AMG  PJ inverter as I  am only  guessing  with this  6 wires transformer design  .    I wish Sean  will do a review on Youtube .    

Shouldn't make a difference.  The 2 phases being imbalanced really won't hurt anything except a voltmeter.  240v appliances see the total, and 120v appliances see their particular phase.

If you're really bothered about the phases having different voltages, you can technically correct that yourself by adding a few turns of wire to the transformer on the low phase (L side of the appropriate phase, not the junction "N").

Expect the sine wave to begin flattening out under moderate loads 😉.

L1  and N  is 2  wires  then  L2 and N is 2 wires  .   That account for the 4  wires  but  there is 2 more wires  for what ? 

There is  the  2  wires for the  primary  input for the transformer .   I  like to know if it is  36vac  or 32vac  or  30vac  or  26vac which is too low for  48v DC  battery .  If the transformer  core is ASL4 then  no more than  3000 watts  continuous   as my  8kw PJ  is a ASL 4  .   Thank you  for the first review on this forum .   

Mine only has 4. See pictures. 
 

Mine only has 4. See pictures

I see 4 white wires  L1  and  N  and  then  L2  and  N  on the right side  of picture .     On  the left side is 2 black  wires which is the  primary  wires to the control board  FETs  ac side heat sink .   This is the new  AMG  transformer  that  replace all  the old  5 wires  transformer .   That why the  5 wires  15kw  that was  800 dollars  is now  1500 dollars  and  will be no more  when all is sold on ebay .   

Hey @scoops, out of curiosity, can you provide the following info about the transformer in your inverter?  I'm more curious than anything else...see if I can guess approximately what the max continuous load should be 😉.

• how many strands of wire are on the output AC lines (you can pull back the white sheath to see the strands)--likely all 4 AC output lines will have the same number of strands (being an "AMG" inverter)
• how many strands of wire on the "MOSFET" lines (the wires bolting directly to the heatsinks)?
• what's the nameplate tag on the transformer (if provided)?  (This has voltages and core size listed.)

The dc side appears to have 10, and looped twice before entering transformer.

here is a picture of the label.

Haha, so they ARE copying the Genetry spec somewhat.........

...they used to be 36v/230v, but the GS spec is 32v/240v.

10 strands on the "DC" side...and if there's 2 strands on the "AC" side, that's basically textbook GS6 spec.  Have my doubts as to whether it really is an ASL2--that's a really tiny tranny core.

Gotta love it.

If it's got a single strand on the "AC" side, that'd quantify the ASL2 core--but I quite doubt it, as it'd be overheating pretty easy at 3kw.

Well I can’t easily see the strands on the white wires. They are heat shrinked, but they feel like just one wire in each

the diameter of the transformer is about 7” if that means anything.

I was hoping to get 6000 watts out of it. I Will say the fan is very powerful, and comes on with a 1000 watt load.

i will do some testing tomorrow and also take temp of transformer at various loads.

7" diameter...well, that puts it at definitely smaller than a GS6 tranny (~8" diameter).  Right in the range for an ASL2 core actually.

You'd definitely be able to feel if there were 2 strands on the white wires (just checked a GS6, haha!)  Single strand AC mains side and an ASL2 core kinda puts you in the 3kw continuous max before overheating...due to a lack of wire on the AC mains side.  Which is kinda implied/indicated by the fan coming on with a 1kw load.

Hey, it's a PJ, what else did you expect??!

Lol.  True, I didn’t have high expectations going in. Truth be told I’ll be driving this from a 3k dc 48Vdc generator so I figured that it would run cooler if I had the 6000 watt ceiling. It will be interesting to see how hot it gets at 3000 continuous. 

Haha, so they ARE copying the Genetry spec somewhat.........

...they used to be 36v/230v, but the GS spec is 32v/240v

Transformer in picture  look smaller than  my old  ASL4   five  wires  transformer .    I  just measure the  ASL4  transformer  is 7 and 1/2  inch diameter .   Your picture look the same as  the tiny  mini rev 11.1 control board  that  has no charging and no  ac output  board  .  The   old  9kw PJ  with the ASL5  five wires transformer and separate ac output board  will  output  more than  the AMG  6 wires transformer  for sure .       

PV, if you get an inverter that will do 6500w continuous for $527 and all you have to add are some faster fans, then I would say you did well!