New Lux Power LXP-LB-US 12k / GSL-H-12KLV-US with 200A AC Passthrough Current (US Market)

[Sun in Lithium]

Typical results.

OK good to know.
I'm not trying to bash th Lux 12k, or compare it to a lvx6048 totally different inverters.
I just put the test in there for a reference to show that It isn't that way with every inverter.

I originaly noticed the difference in my led lights.


I'm just One guy, trying to find a suitable inverter at a reasonable price, for people in my area that have no access to the grid. Or they can't afford the $80,000 bill to bring it in.

In general I really like the lux 12k so far it has alot going for it.

I've installed a dozen lv6548 inverters.
Good inverters but they have there short comings.

My question was not to put the lux 12k down or to say it is the same as the one from eg4.

 

[Sun in Lithium]

Overload at 12K? Which load? For how long? Can you post a video of that. That would be interesting to see. I've pulled 12kW from mine for hours without issue so far.

It was a couple different loads. But the main one was a plasma clutter.
I will try to do a controlled test.

Did you test yours connected to the grid?
Or totally offgrid?

 

[Sun in Lithium]

Your post concern me about over load at 12K, because I also bought 2 of the older 12K units. One of my reasons for buying two units was because of all the Sol-Ark posts about the inverters nuisance over loads. I would had hoped that with two 12K Luxpowertek units in parallel that I would almost never overload ... at least not at 12K. In my case, I am only off grid during a power outage, but I want to be prepared for a major power outage should something happens.

When I said 12kw that was just the one inverter. If you have 2 in parallel that's alot of power. Also just one lux 12k will start quite a bit of indutive loads. You just might notice a slight hesitancy in the motor because of the momentary voltage drop.

 

[Quattrohead]

Can you post that as a video or scope reading

Not anytime soon, I'm up to my eyeballs in building a home. So you just going to have to believe my casual observations for now.

 

[Quattrohead]

Having said this, I have seen them causing cheap LED lights on dimmers to flicker but that is not the same as voltage sag under heavy load. Even my solark makes the cheap builder lights on cheap Amazon dimmers flicker.

 

[Sun in Lithium]

You will have the same voltage swings with any HF inverter. Maybe I need to make a video about this.

I do agree there does seem to be alot of confusion and disagreements on this subject.

I'm not so clear on it my self.

For instance the lvx6048 looks to be a HF 240v inverter with a center tap transformer. On the other hand for instance a samlex 4000w 120v inverter
Switchs the power at 24v and uses a transformer to boost the voltage up to 120v. Notice the massive bus bars going to the transformer.

The lvx6048 has a constant draw of 140w well offgrid.
I would suggest that it may be driving all the mosfets (or what ever their are using) that way it can respond quicker.


I'm not saying this is good 140w constant draw is crazy.

My test show the Lux 12 us to only draw 55w which is great.

Edit
I think I found out whey the lvx6048 uses so much power the transformer draws 0.5 amps at 240v that's 120w ?

 

[FilterGuy]

Technically HF with center tap transformer. That little transformer makes a massive difference versus not having one at all. And for simplicity sake, I just call it LF if it has a transformer. But you are correct. It is somewhat of a hybrid actually.

Yes, the lvx6048 is a bit of a mix. The output transformer is an autotransformer with a center tap that is across the 240V HF inverter output. The autotransformer is in the circuit even when in passthrough mode.

The autotransformer does make a significant difference, but it is hot as much as a true isolation transformer would.

Just shows how much they are not spending on development.

I assumed not using a toroidal transformer was more of a cost-cutting decision than a lack of development investment. The R&D is probably about the same either way.

 

[Luxpower_Gilbert]

OK good to know.
I'm not trying to bash th Lux 12k, or compare it to a lvx6048 totally different inverters.
I just put the test in there for a reference to show that It isn't that way with every inverter.

I originaly noticed the difference in my led lights.


I'm just One guy, trying to find a suitable inverter at a reasonable price, for people in my area that have no access to the grid. Or they can't afford the $80,000 bill to bring it in.

In general I really like the lux 12k so far it has alot going for it.

I've installed a dozen lv6548 inverters.
Good inverters but they have there short comings.

My question was not to put the lux 12k down or to say it is the same as the one from eg4.

Simple solution for HF inverter is to add a auto transformer parallel to the inverter output or breaker box…

 

[Sun in Lithium]

Simple solution for HF inverter is to add a auto transformer parallel to the inverter output or breaker box…

I agree that it should help with 120v loads
I'm having a hard time understanding how a center tap transformer would help with 240v surges.

My understanding is a coil like in a buck converter resists change. Therefore when It is given a pulse it smoothes it out.

That makes sense to me. The Low frequency inverters, do there switching at a low frequency and send it through a isolated transformer which is usually used to up the voltage and smooth the ac wave.

But AC power by nature is change.
That's why a coil will block it unless there is a secondary Coil absorbing the magnetic flux.

How can a center tap transformer help for more than half of the ac wave?


Please correct me if I'm wrong, I'm not an electronic engineer.

 

[robby]

I assumed not using a toroidal transformer was more of a cost-cutting decision than a lack of development investment. The R&D is probably about the same either way.

A lot of people do not realize how much more a toroidal transformer equivalent costs.
They are the only Transformers I have left in my Inventory of Transformers, I dumped the rest due to the Wife storage area needing clearing out.

 

[Not Aerosmith]

My 12k been running 7 months now 24/7, been runing on closed loop communication for 6 months for my DIY lifepo4 with daly bms, but for some reason with the latest update it, it will not work, lux recommend to use battery voltage for now.. when using battery voltage must set it correctly…

Still using battery voltage or did Lux resolve the problem with another firmware update?

 

[Luxpower_Gilbert]

Still using battery voltage or did Lux resolve the problem with another firmware update?

Still using battery voltage but i use HA to control my DIY battery with %.

 

[Luxpower_Gilbert]

I agree that it should help with 120v loads
I'm having a hard time understanding how a center tap transformer would help with 240v surges.

My understanding is a coil like in a buck converter resists change. Therefore when It is given a pulse it smoothes it out.

That makes sense to me. The Low frequency inverters, do there switching at a low frequency and send it through a isolated transformer which is usually used to up the voltage and smooth the ac wave.

But AC power by nature is change.
That's why a coil will block it unless there is a secondary Coil absorbing the magnetic flux.

How can a center tap transformer help for more than half of the ac wave?


Please correct me if I'm wrong, I'm not an electronic engineer.

With 240v load, it will bypass the auto transformer and inverter will support it. The auto transformer will auto balance between the 2 leg output of the inverter when supporting 120v…

 

[Sun in Lithium]

I always imagine how much energy a coil can store after being shocked by them so many times ? the energy has to go somewhere. And evening out a large surge is perfect! There is a reason people like LF for inductive loads. It is a fantastic configuration. A charged up coil (so to speak) connected to a low resistance coil on the other side (the inductive load). Just makes sense

I haven't done the math on it, but even a small transformer helps with inductive loads

It makes sense when you're talking about DC current. Unless you're sure you go shocked by ac power ?. They do feel quite a bit different, Lol

I'm just struggling to understand the theory behind it in AC power.

Yes that has been my experience as well.
The heaver the inverter the better it can handle surges.
I'm just trying to understand why.

What does your book say?

 

[Will Prowse]

It makes sense when you're talking about DC current. Unless you're sure you go shocked by ac power ?. They do feel quite a bit different, Lol

I'm just struggling to understand the theory behind it in AC power.

Yes that has been my experience as well.
The heaver the inverter the better it can handle surges.
I'm just trying to understand why.

What does your book say?

Just DC coils actually. And yes need to go home and figure it out. I did transformer stuff in school but it's been a while ? I would imagine the field pulling back and forth in a circle. But does it actually have the same inertia, so to speak, as inductor. I think a collapsing field would help going in either direction even if it was for a millisecond. And that can be all it needs for most inductive loads. That need for current is massive at startup, but it is for such a short duration. But yes, I don't have any numbers. Hopefully a EE can chime in before I find out for myself

 

[Quattrohead]

Not anytime soon, I'm up to my eyeballs in building a home. So you just going to have to believe my casual observations for now.

Just caught them at 95% load and as you can see the average voltage maybe went down to 119.5v. Toasty around the control panel would be an understatement lol

 

[Sun in Lithium]

Does anyone have a suggestion for a good all around scope?

 

[Eddie_LuxPowerTek]

Motor loads & Luxpower inverters?

The discussion that followed @Sun in Lithium 's demonstration of the voltage swing issue when hooking up the pump has sparked considerable interest. I would like to share some insights after discussing the matter with the head of our R&D team. While this information may not be new to some, it is quite enlightening for me, as I am not an electrical engineer.
We appreciate that @Sun in Lithium brought up this topic, and we welcome more people to point out any questioning points or weaknesses we may have. (That is how things get improved we believe)

1） Situation description.
In a running system, with stable load conditions, there is no issue with voltage fluctuations during the switch from off-grid to on-grid. However, when a large motor load is suddenly started or starts up the inverter with large motor loads, there are two possible outcomes. One is that the motor load may fail to start due to the limited surge resistance capability of our current machines. The other outcome is that it may cause voltage oscillations, but the system will stabilize and return to normal operation within approximately 1 second after the motor load is started.

The approximately 10% voltage fluctuation typically occurs during the impact of heavy loads, especially motor loads. It is considered a normal phenomenon for the voltage to recover within around 1 second, and it also complies with the quality standards of HF inverters. The duration of this voltage fluctuation for LXP-8/10/12k models should be within a few hundred milliseconds.

2）Is there still room for improvement in terms of the load capacity for inductive loads and motor loads in the short term?
Answer: YES. We have a small team specifically working on these improvements through firmware development. During motor startup, there is a momentary surge in current, often reaching 3-5 times the rated current. This is primarily due to the need for the motor to establish its magnetic field. This startup process can be managed using advanced control algorithms that employ soft-start techniques for magnetic field establishment. However it can cause a drop in voltage, once the field excitation is complete, the motor returns to its rated power output.

3）Why HF inverters?
The advantage of a high-frequency inverter is that it doesn't generate significant surge currents, which means the battery won't experience sudden impacts. This makes it more suitable for energy storage systems. Additionally, high-frequency inverters have other obvious advantages: they are lightweight compared to low-frequency models, have high efficiency, and offer greater flexibility in control.

When it requires a fast switching between off-grid mode and on-grid mode, high-frequency inverters do not generate significant surge currents, unlike low-frequency inverters. This is important because large surge currents from low-frequency inverters can potentially cause circuit breakers to trip during the transition. The reason for this is the "residual magnetism effect" in transformers. It may cause hundreds of amps of current in an instant.

4） Do we recommend connecting external devices?
It is not recommended to connect external devices to the high-frequency inverter, nor is a soft-start device required.
Time being, the maximum surge current that LXP products can handle is around 1.5 times the rated current within 500ms.

Regardless, feel free to continue the discussion and feel welcome to provide further insights on the above notes I learned.
Thank you all!

 

[Sun in Lithium]

Motor loads & Luxpower inverters?

The discussion that followed @Sun in Lithium 's demonstration of the voltage swing issue when hooking up the pump has sparked considerable interest. I would like to share some insights after discussing the matter with the head of our R&D team. While this information may not be new to some, it is quite enlightening for me, as I am not an electrical engineer.
We appreciate that @Sun in Lithium brought up this topic, and we welcome more people to point out any questioning points or weaknesses we may have. (That is how things get improved we believe)

1） Situation description.
In a running system, with stable load conditions, there is no issue with voltage fluctuations during the switch from off-grid to on-grid. However, when a large motor load is suddenly started or starts up the inverter with large motor loads, there are two possible outcomes. One is that the motor load may fail to start due to the limited surge resistance capability of our current machines. The other outcome is that it may cause voltage oscillations, but the system will stabilize and return to normal operation within approximately 1 second after the motor load is started.

The approximately 10% voltage fluctuation typically occurs during the impact of heavy loads, especially motor loads. It is considered a normal phenomenon for the voltage to recover within around 1 second, and it also complies with the quality standards of HF inverters. The duration of this voltage fluctuation for LXP-8/10/12k models should be within a few hundred milliseconds.

2）Is there still room for improvement in terms of the load capacity for inductive loads and motor loads in the short term?
Answer: YES. We have a small team specifically working on these improvements through firmware development. During motor startup, there is a momentary surge in current, often reaching 3-5 times the rated current. This is primarily due to the need for the motor to establish its magnetic field. This startup process can be managed using advanced control algorithms that employ soft-start techniques for magnetic field establishment. However it can cause a drop in voltage, once the field excitation is complete, the motor returns to its rated power output.

3）Why HF inverters?
The advantage of a high-frequency inverter is that it doesn't generate significant surge currents, which means the battery won't experience sudden impacts. This makes it more suitable for energy storage systems. Additionally, high-frequency inverters have other obvious advantages: they are lightweight compared to low-frequency models, have high efficiency, and offer greater flexibility in control.

When it requires a fast switching between off-grid mode and on-grid mode, high-frequency inverters do not generate significant surge currents, unlike low-frequency inverters. This is important because large surge currents from low-frequency inverters can potentially cause circuit breakers to trip during the transition. The reason for this is the "residual magnetism effect" in transformers. It may cause hundreds of amps of current in an instant.

4） Do we recommend connecting external devices?
It is not recommended to connect external devices to the high-frequency inverter, nor is a soft-start device required.
Time being, the maximum surge current that LXP products can handle is around 1.5 times the rated current within 500ms.

Regardless, feel free to continue the discussion and feel welcome to provide further insights on the above notes I learned.
Thank you all!

I'm very glad to hear luxpowertek is willing to act on Suggested improvements.

Not all manufacturers are.

I would like to point out that 27v swing on 120v power supply is is closer to 20% swing.

It hasn't caused any apparent issues for me it's just more of an annoyance. With the lights.

 

[Sun in Lithium]

Overload at 12K? Which load? For how long? Can you post a video of that. That would be interesting to see. I've pulled 12kW from mine for hours without issue so far.

I did do some load testing with 2 eg4 chargeverters And a 4500w 240v heater and I was able to get over 13.5kw

So my last observation was false.

On the other hand, what I think, I was noticing earlier with my plazma cuter was the inverter couldn't handle the change in load. I wasn't even going over 12kw total draw.

This was confirmed by my load testing
When pulling 11kw from the inverter if I turn off the 4800w heater the inverter would trip. Also if I tried to turn on the second eg4 chargers well one of the eg4 chargeverters was running both set to 75 charging amps it would also trip the inverter.

The inverter shows no alarms, or gives an explanation for why it tripped

I am working with luxpowertek on this.
They are on it.

Keep in mind this is strictly off grid.

I get the feeling this inverter was mainly tested on grid. And should work quite well for that application.

Let's make this work. ?