Just got my new PJ LFPSW-8000 Inverter

Ah thanks for the explanation, it makes sense now. I've never quite got my head around the US split-phase system. In the UK and most of Europe domestic supplies are usually single phase 230v, industrial supplies usually 3-phase.

Ah thanks for the explanation, it makes sense now.

Your welcome .   The old  5 wires transformer has  the one secondary as a 240vac winding  and the center tap makes two 120vac  secondary  for L1  N  L2 .   The AMG has 2 separate  secondary windings and both are 120vac  so not good for L1  N  L2  .    PJ in China do not understand  240vac split phase  and advertise the AMG as having  more output but  actually output less with the rev 11.1  control board .    

No idea where you get this.

The "AMG" version is based off the GS concept for rewiring the transformer for full output at different voltages.  It is equally at home with a single-phase output, as well as a spit-phase output.  Just rewire it as necessary.

Only difference being that the PJ version only ever regulates 110v from one secondary winding...the other winding is unregulated and appears to also be unfiltered.

I dunno where you get all this.  There is no internal difference to the transformers, just how the wires are presented.  There is no magic "5-wires" and "6-wires" transformer difference.  The only practical difference is how the wires are presented.

I have a "5-wire" ASL9 PJ transformer.  It still has 2 secondary windings, just the same as the "AMG" transformers.  The only difference on the "5-wires ASL9" is that the "middle" wires of the windings are both crimped into a single lug.  I could literally cut one of the secondary windings' wires out of that lug, crimp them into a separate lug, and *bam* I'd have a "6-wire AMG" transformer.  (Sure, the 2 windings probably won't be balanced voltagewise, but that has nothing to do with the point I'm making here.)

Again, this is distinction with absolutely no real-world difference.

EVERY SINGLE PJ TRANSFORMER with a split-phase output...has TWO 120v secondary windings, wired in series.  The junction point between the 2 coils is the Neutral line.

If the two windings are put in series inside the transformer...if they're put in series at the crimp lugs on the end of the transformer wires...or if they're put in series externally with an "AMG" jumper wire, it makes NO electrical difference.

I've even rewound an older copper-wound PJ transformer (with the colored insulation wires)...and the windings were series-connected internally at the "neutral" junction wire connection.

If you unwind a PJ transformer, you'll find all 3 windings (the two 120v windings, and the "DC" side winding) are each separated with a layer of clear plastic wrap.

 I could literally cut one of the secondary windings' wires out of that lug, crimp them into a separate lug, and *bam* I'd have a "6-wire AMG" transformer.  (Sure, the 2 windings probably won't be balanced voltagewise, but that has nothing to do with the point I'm making here.)

I  know the point you are  making  that PJ let the buyer decide if the inverter is  120vac single phase  or can be  jumper to be  240vac  single phase  with one 120vac line .  PJ on ebay say  not  L1  N  L2 .   I know it can be wired L1  N  L2  to the house but  the 2 windings  may not be balanced voltagewise .   Is that the reason  PJ  say not L1  N  L2  ?

IF  jumper for  direct  240vac single phase  60 hz  and   L1  and  L2 not balanced  is ok  to start an  inductive load  but if wire split phase  and a large load is on  one of the 120vac line then  the inductive  load   will not get the full 240vac   output  and may not start .   That split phase may have an unbalanced  line  and  reason to not  L1  N  L2  but  wired as L1 and L2  direct to the well pump  without  neutral   and ground  connect to  the  inverter case .  

I have always understood that warning to refer to the AC input--which can't handle a 3-wire AC input ("L1 N L2"), or the inverter will blow up due to a backfeed condition.

Beyond that, there is absolutely no issue with split-phase output from an "AMG transformer."  For that matter, there isn't any intrinsic design difference between the "5-wire" transformers and an "AMG 6-wire" transformer. 

Phase voltage imbalance is in most cases a complete non-issue--it's just the customer who notices it.  As most appliances accept a fairly large voltage range, it generally won't hurt or affect appliances in any way.

Most of the PJ inverters only regulate output voltage from a single 120v phase anyway--and often don't even have an AC output filter cap on the other phase.  This is even on the "5-wire" transformers, one of which I have on my bench right now.  The L2 wire goes directly from the transformer to the terminal block.  No filtering or regulation whatsoever on the other phase--and that's a v9.0 PJ inverter with a copper-wound transformer.

On 1/24/2022 at 7:26 AM, Sid Genetry Solar said:

Can you provide a photo of the control board pot?

If there's 2 knobs, the other will adjust the internal battery voltage setpoints.  Differentiating is as simple as twisting one of them...if the output voltage doesn't change, put it back where it was, and twist the other one.

There's no science/rhyme or reason for the voltage adjustment...you'll just have to fire the inverter up with the cover off, and twist the knob while measuring the output voltage.

 

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 😉Two pots, VR1 and VR2

LF-ASL2-AMG4

ASL2!? Thats even smaller than the one in my 8k 240v unit (ASL3). And my 8k unit can only do 3.5kW continuous.

But I notice they've changed the primary voltage from 18v to 16v, which should help reduce the flattened peaks on the sine wave under load.

2 minutes ago, Paul said:

ASL2!? Thats even smaller than the one in my 8k 240v unit (ASL3). And my 8k unit can only do 3.5kW continuous.

But I notice they've changed the primary voltage from 18v to 16v, which should help reduce the flattened peaks on the sine wave under load.

From what little I understand, the chassis number may not be as important as the degree of copper windings?

Copying Genetry Solar I see, haha 😉

It's hard for them to see my very detailed specification documents cross their desks without wanting to test some of the stuff themselves, haha.

13 minutes ago, RobertM said:

From what little I understand, the chassis number may not be as important as the degree of copper windings?

That would be correct. 

The "ASL2", "ASL3", etc., etc. are transformer core sizes (dimensions are PJ's own specification; these aren't standardized specifications).  A smaller core isn't necessarily a problem--except that it limits the amount of wire you can get around the core.  As far as I know, the wire (or lack thereof) is basically the limitation of the transformer's maximum wattage.

In theory, if wire had absolutely zero resistance, you could theoretically get an unlimited amount of power out of a very small core.

Curious how many strands the "battery" winding has?  I guarantee you the "output" windings will have a single strand of wire--and wouldn't be surprised if it isn't thin wire (i.e. 2.0mm diameter).

I measure the copper wire at 3mm.