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Paralleled EG-4 6500EX on a 120V single phase system?

If you look at OP’s picture where both inverters have - output connected to neutral, does this still apply?

Anyway I think we both understand this and haven’t agreed before in other threads on the notation difference explaining why some people insist on 180 degrees so we can agree to disagree again
That drawing is incorrect.
 
That would be a dead short. (Which could cause "magic smoke")
But they are not at zero degrees (except for once every second)
They move through the full 360 degrees.
OK, so what is the difference that causes no magic smoke in a proper parallel config to double 120V capacity?

(And I’m assuming the inverters are frequency synchronized)
 
IMO this depends on how the inverters are connected and programmed. I don’t understand how your point of view on configuring phase angles generalizes to handle both split phase and wye configurations in the same 120V inverter
Let's try a simpler explanation.
If you place two 12v batteries in series.
You can still measure 12v at each battery. But together, you will measure 24v.
Multiply the voltage by 10, and reverse the current flow 60 times per second.
That is split-phase.
 
I don't understand your question.
In two different configurations, you say it is 0 degrees.

(Config 1 - two in parallel, to give 120V)
(Config 2 - two in series, to give 120/240 or 240V)

There is something different in config 2, such that if you connect the hot terminals together, magic smoke goes out. If Config 1 and Config 2 are identical, giving identical 0 degree configuration will result in same behavior. But we know it is not the same, because they behave very differently

It should be because one of these configs will have one inverter flipped in the wiring.
 
In two different configurations, you say it is 0 degrees.
0 degrees from each other.
(Config 1 - two in parallel, to give 120V)
(Config 2 - two in series, to give 120/240 or 240V)
Correct
There is something different in config 2, such that if you connect the hot terminals together, magic smoke goes out. If Config 1 and Config 2 are identical, giving identical 0 degree configuration will result in same behavior. But we know it is not the same, because they behave very differently
The only difference is in how they are connected together.
If you connect two ends of a power source , it's a dead short.
Same goes for two sources in series or parallel.
It should be because one of these configs will have one inverter flipped in the wiring.
Yes, the connections are different for series and parallel.
Just like every other power source. (Batteries and solar panels, for instance)
 
OK, so in the series split-phase configuration, if the inverter manufacturer insists on measuring voltage and interpreting configuration settings with the - probe at neutral, I feel we should follow their terminology and call one of those 0 degrees and one of those 180 degrees. (EG V1 = L1 - N, V2 = L2 - N). Otherwise stuff will not work. (I've been trying to find an example EG from victron on how they interpret this, but I was not able to in the allotted time).

If the inverter manufacturer insists on measuring / interpreting the settings the same direction on both legs (EG V1 = L1 - N, V2 = N - L2) then it should be 0 degrees.

What would you call (series or parallel) a split-phase inverter that can be configured in either L1/L2/N, or L1/L1/N (120V) mode, without changing any wiring inside the inverter (and it may not even be possible to change if the neutrals are bonded together on a busbar and can't be swapped). I'd prefer to refer to one of the inverters as configured in 0 degree mode for 120V and 180 degree mode for split phase because we have not done any physical rearranging of how the inverters are wired up.
 
OK, so in the series split-phase configuration, if the inverter manufacturer insists on measuring voltage and interpreting configuration settings with the - probe at neutral, I feel we should follow their terminology and call one of those 0 degrees and one of those 180 degrees. (EG V1 = L1 - N, V2 = L2 - N). Otherwise stuff will not work. (I've been trying to find an example EG from victron on how they interpret this, but I was not able to in the allotted time).

If the inverter manufacturer insists on measuring / interpreting the settings the same direction on both legs (EG V1 = L1 - N, V2 = N - L2) then it should be 0 degrees.

What would you call (series or parallel) a split-phase inverter that can be configured in either L1/L2/N, or L1/L1/N (120V) mode, without changing any wiring inside the inverter (and it may not even be possible to change if the neutrals are bonded together on a busbar and can't be swapped). I'd prefer to refer to one of the inverters as configured in 0 degree mode for 120V and 180 degree mode for split phase because we have not done any physical rearranging of how the inverters are wired up.

You can call it anything you want. (And would be wrong)
I'm just trying to help you (and anyone else reading) understand what it is, and should be called.
Split-phase is really simple.
But for some reason people try to over complicate things.
 
You can call it anything you want. (And would be wrong)
I'm just trying to help you (and anyone else reading) understand what it is, and should be called.
Split-phase is really simple.
But for some reason people try to over complicate things.
The reference you've sent out on YouTube I believe is clear about the measurement polarity of the probes (if he doesn't say it explicitly, it can be seen with how he puts them on the lines). I'm not sure why that measurement direction is better than the other one.

I think it's super helpful for people to know that the 180 degree viewpoint merely happens because the measurement or programming polarity is flipped. And then they can move on / understand it more deeply.

And I think even if programming is "wrong" on how an inverter interprets the phase angle configured into it, you have to enter it wrong too to match.
 
The reference you've sent out on YouTube I believe is clear about the measurement polarity of the probes (if he doesn't say it explicitly, it can be seen with how he puts them on the lines). I'm not sure why that measurement direction is better than the other one.

I think it's super helpful for people to know that the 180 degree viewpoint merely happens because the measurement polarity is flipped. And then they can move on / understand it more deeply.
I don't mention that, because it just confuses people more.
Unless someone brings up using a scope.
This is the only time that how measuring leads are connected, matters.
A scope is the only time that an individual half cycle is displayed on a screen.
 
And I think even if programming is "wrong" on how an inverter interprets the phase angle configured into it
It's not phase angle.
It's physical connection.
In parallel, the Lines are connected together.
In series, the Lines are positioned at either end.
When you program the inverter for "180" , it's referring to the physical connection.
Phase angle is always the same (in sync) , for series or parallel.
 
You can call it anything you want. (And would be wrong)
I'm just trying to help you (and anyone else reading) understand what it is, and should be called.
Split-phase is really simple.
But for some reason people try to over complicate things.

Totally agree.

Here is thought experiment; take 2 oscilloscopes and connect one L1 to N and the other L2 to N. Would each display a sinusoidal wave form? (Yes) And if you were to super impose one wave from on top of the other would you see just one wave form (No) or you would observe two distinct waveforms (Yes) that mirror each other about the time axis. At any given point, when one waveform is at its positive peak, the other would be at its negative peak, and vice versa.

Its a matter of perspective; from the power generation side is a single phase, which is passed through a center taped transformer to produce 2 distinct waveforms, which just happen to be 180 degrees out of sync with one in other.

Single phase, split phase, its semantics really.
 
Its a matter of perspective; from the power generation side is a single phase, which is passed through a center taped transformer to produce 2 distinct waveforms, which just happen to be 180 degrees out of sync with one in other.
Incorrect
There is only ever one waveform.
 
A transformer changes voltage from input to output.
It can't create phases.
 
2 oscilloscopes 2 waveforms, 180 degrees out of sync on the time scale. One phase, 2 waveforms, really?
 
Not sure if there is, but certainly not hard to do. Take 2-3K inverters, like my Growatts, configure for 120/240 (out of phase 180 to neutral) and put them in one enclosure and in essence you have a 2 phase inverter. I suspect the 6000XP does the same unless it has a auto transformer, but then it would not be truly transformer less.
Correct. Since this simulates a split phase output it works out fine. Not just semantics of mislabeling a split phase as 2 phase. They are different in how each is generated.
 
The confusion is because Neutral is not a leg of a "phase". It is a tap in the middle of the transformer. It appears to be "180 out" because you are taking the reading with neutral as a "common" which it is not, it is a tap. . . it's where you "SPLIT" the phase in two. There is only one magnetic wave on the winding producing +-240v L1 - L2. The wave is exactly the same on the first half of the winding as the second, however if you take a reading using N as a common, it will appear to be 180 out because you have the polarity of the scope leads 180 out. To properly look at the phase on a scope you would need to see L1->N and N->L2 thus the first trace would have L1 on the clip N on the probe. The second would need N on the clip L2 on the probe. This will likely cause a short in your cheap scope as it will want clip side of the probes to be common for both traces, thus shorting L1 to N creating smoke. If you have a scope with isolation, and you do it this way you will find the waveforms are 100% in sync.

The split phase inverter simply creates TWO 100% synchronized outputs of 120v lets call them A and B.
A-L1 connects to L1out
A-L2 and B-L1 are tied to N.
B-L2 connects to L2out.

Both A-L1 and B-L1 must rise and fall at the same time.
Both A-L2 and B-L2 must rise and fall at the same time.
This creates +-240v between A-L1 and B-L2

This simulates tapping a 240v transformer 1/2 way down the winding.

When L1 is negative for the 120v on the L1-N side of the split, N is negative for 120v on the N-L2 side of the split, and L1 would be negative for the full 240v. One wave, one spinning magnet, one-phase, tapped in the middle to grab a reduced voltage. I know it seems like there are two phases but there is only one being "shared" by tapping it in the middle to grab a different potential.
 
Which brings us to AMPS. The EG4 is capable of producing 25A (240*25 = 6000). You can pull 25A from 240. Or you can pull 50A from 120. by pulling 25A from each side of the split. You would probably want to make sure the mini-splits are on different sides, one on L1 the other on L2. Also make a modicum of effort to not skip every other slot in the panel putting everything on the same side, sounds like you didn't half-wire for the 110 so likely not a problem.

Finally, there are scientific explanations on why motors and such are more efficient at 240 than 120, it's pretty esoteric. Suffice it to say, way more often than not, they just are. I had a datacenter all the gear was 110-240 auto-ranging. We were banging pretty close to 24A @ 120v. Instead of dropping another 120, we dropped a 240v/30A. Moved all the gear draw went to a hair over 10A, so 2800W -> 2450W, about a 10-12% reduction in overall power usage. (120*24 = 2880W, 240*10 = 2400W). YMMV.
 
And it's not really "semantics" its mechanical. One motor/generator spinning one magnet = 1 phase. Three motors spinning three magnets = 3 phase. The difference is in the wiring and the way the generator outputs are connected to the service delivery point.
 
I think it's about time the USA switched to a standard 240 volt supply, convert from inches to metric and start driving on the other side of the road like my native land.
The split phase system blew my mind when I arrived here along with wire nuts but I'm happy enough with it all now.
 
ksmithaz1 & Tim; Thanks for the explanation. This has been an educational thread. I certainly see the perspective when the power source originates from one generator/winding. Somewhat less initiative if there are two power sources as in the case of paralleled inverters.

Speaking of which can the EG4 6000XP be configured just 120V (so all 50A would be available on one leg) or must be 120/240?
 
Speaking of which can the EG4 6000XP be configured just 120V (so all 50A would be available on one leg) or must be 120/240?
No it cannot be configured for 120 volts only, but you can parallel multiple of them together to get your total capacity up.
 
I think it's about time the USA switched to a standard 240 volt supply, convert from inches to metric and start driving on the other side of the road like my native land.
The split phase system blew my mind when I arrived here along with wire nuts but I'm happy enough with it all now.

Metric: ALL IN. We should already be there it's just a number, I could get behind legislation to push this forward.

While we are at it, get rid of daylight savings time. I get up with the sun anyway, my clocks don't move.

Driving: Kiss my big toe you oaf! Odd that Great Britain sanely adopted the metric system, and converted to decimal currency, but then decided to keep driving on the wrong side of the road from most of the rest of the world. :ROFLMAO:

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240v: Meh, not sure how I feel about this one.
Too much stuff runs 110 already, and most of it is very lightweight. 240v for all major appliances maybe. For a table lamp it's sort of irrelevant, most portable chargers and stuff with ac/dc bricks auto-range already. I think split phase adds a safety angle somewhere, by grounding the Neutral, when you only have 1 output winding. A worldwide DC bus standard might be interesting.
 
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