EG4 3kW won't charge with a generator

[Grimmster]

Sadly there is also a GOTCHA on the cheaper Inverter/Charger or AIO Combo's. The cheaper models often do not output a consistent 60Hz or 50Hz (pending on model) and very often will output at 49 or 59hz and in cases like 120V may only output 119V. While this is not significant enough to be a problem, over time things will "slip" accordingly like wall powered clock time.

I assume you mean the really cheap junk. I've never seem frequency as a complaint for units like EG4 and Growatt.

 

[Mithril]

I assume you mean the really cheap junk. I've never seem frequency as a complaint for units like EG4 and Growatt.

I actually have issues with my EG4 3000 and my Rackmount UPS sometimes not viewing the inverter output as clean enough.

 

[Rednecktek]

I actually have issues with my EG4 3000 and my Rackmount UPS sometimes not viewing the inverter output as clean enough.

I've seen that with the cheaper APC units. Got a TrippLite in there and my alarms shut up.

 

[Mithril]

I've seen that with the cheaper APC units. Got a TrippLite in there and my alarms shut up.

I wouldn't call this a cheaper unit, it's a 2U rackmount with an external battery plug. Maybe I should connect to the nic and see if the web management has any tweaks

 

[KonaColin]

Looking at buying the EG4 6500 unit and was hoping to use one of 4 of our generators as an a/c input to charge system batteries when needed.

Should I anticipate difficulty?

 

[50ShadesOfDirt]

The inverter manual will help determine the level of "difficulty"; whatever they specify is what you have to work with.

I'd guess that your choice of (1 of your 4) generators still puts out either:
- too much THD for the inverter you have (you can look this up for your gen model)
- varies a bit too much for hz/voltage (sometimes adjustable at gen, depending on model and available tech notes)

If the desired inverter (and it's manual) states a range of what kind of power it will eat, not much you can do about it, except give it power in that way. Anything else, and you might have a "void the warranty" scenario. If it doesn't state the range, you can only test it ... the vendor may or may not have tested all possible combinations (and probably didn't).

My magnum ms4024pae eats any kind of gen power, and from my westinghouse wgen9500df the THD is around 20% (voltage was tweaked for it a bit, when I first got it in, but THD remains about the same, due to stator/rotor design for that model). Most newer (LF/HF?) inverters aren't designed to eat any kind of gen power, so a design restriction is in place ... if you buy such an inverter, you are stuck with that requirement. I don't fully understand why these AiO inverters can't eat any kind of power, whereas most Tier-1 (LF) inverters can, as the documentation/research isn't easily found yet.

Technically, you could fix it by sticking a high-end power conditioner ($1000+) in between the existing gens and the inverter, or a chargeverter ($400, if you are 48v and such). But at solution price levels, and with conversion losses, might as well buy an inverter-gen (or a chargeverter if it fits the solution).

To differentiate between surges and THD as potential problems elsewhere, you should care more about surge protection than THD protection: surges are proven electronics killers, THD is still nebulous, although it makes for great marketing material wrt generators. The former you can actually do something about in your house wiring (relatively inexpensive consumer SPD's exist); the latter you cannot (there are no easy consumer THD protection devices).

Hope this helps ...

 

[dcg9381]

Looking at buying the EG4 6500 unit and was hoping to use one of 4 of our generators as an a/c input to charge system batteries when needed.

Should I anticipate difficulty?

I would until tested otherwise. I'm with others in thinking that if one of your 4 was an inverter generator, it might be stable enough.
I have not tried to run our system off generator power.
The "chargeverter" is the answer, assuming you're willing to live with the current bug where it will initially overload on start up if you don't have a generator of at least 10KW+.. Apparently successive attempts will make it work.

 

[guyroch]

Sharing a reply I got from EG4 just now when I asked them.

 

[eleceng1979]

The prime mover (engine) is responsible for frequency, adjust the governor down to 60.0-60.2Hz no load. It is probably high. I can promise you that these inverters are not doing THD analysis on your incoming power to qualify it. They care about Hz and volts in that order, Hz is tight, volts not so much. The The irony of using an inverter generator to charge an inverter is amusing. Outback, Schneider, etc. don't require inverter gens, just saying...

Did you make sure the generator neutral bonding was removed if connecting to a bonded panel/inverter? double bonds = double trouble...

 

[guyroch]

The prime mover (engine) is responsible for frequency, adjust the governor down to 60.0-60.2Hz no load. It is probably high.

Interesting, and not sure how I would do that.... google here I come.

 

[eleceng1979]

It is typically a screw adjustment on the carb, usually secured with a nut. The service/user manual should show it. Usually it is adjustable with removing any covers. You need a multimeter capable of reading hz. Cheap ones usually don’t.

Adjust, wait, measure, repeat. You don’t want to be over 60.2-60.5. In a perfect world you should not be over 60.0, but you are playing the range. By adjusting a little above, you get more kw out prior to hitting the low cutoff. Due to no published data from inverter about what is acceptable, you might have to play with no load Hz to see where it connects and disconnects on the low end. Higher than 60 is far worse than lower than 60.

 

[eleceng1979]

it will need adjusted as the genny ages. Per most manuals, I believe it is annual/or 50 hours. As piston(s) wear, worn carbs happen, it changes. There are multiple classes of prime movers. Everything not at a hospital or a large frame are NOT designed for permanent duty and have a 100-200 hour runtime lifespan. This includes portable, pad mount whole home, etc…. Google generator prime mover classification

 

[Markus_EG4]

Hi,

I have the EG4 3kW inverter (3000EHV-48). It charges over 120v AC 'house' power, but not 120v AC power from a generator? Generator is a 3000w Champion, and I have the AC max charge set to 18amp on the inverter, so plenty of 'generator' juice to charge, but it refused to charge.

When I plug the inverter into 'house' AC it charges without changing any settings on the inverter. What I'm I missing?

This setup does not have solar panels connected to it, I mainly use it for a backup power during extended power outages.

Thank you.

The generator function was removed after R&D but the manual still showed this setting. All new manuals do not show the gen setting because the inverter will not accept the generator power if it’s to dirty or if the frequency is off by 1.2 hertz.

I’m sorry you are going through this. But I have seen success with generators that are 2x this size of the inverters. Not cheap harbor freight ones either

 

[eleceng1979]

So you sell an off grid inverter, with an ac input, removed the gen settings from the manual, but show a grid connection? For off grid? With no UL listing. And the target audience is whom?

 

[Markus_EG4]

So you sell an off grid inverter, with an ac input, removed the gen settings from the manual, but show a grid connection? For off grid? With no UL listing. And the target audience is whom?

The failure rate was to high with this function. If this setting was still there I’m sure we would be talking about the unit not working at all. But like I said before you can still use a generator but it needs to be twice the size of the inverter. We are not the only ones that say this. Just because this setting is gone doesn’t mean you can’t use a generator it just needs to be within spec.

 

[50ShadesOfDirt]

We get about 2000 hours out of an inexpensive open-frame (non-inverter) fuel gen; then something major (to me) is needed (engine, stator/rotor). It is then recycled and fed into the next one. Because it's open-frame, little problems are easily fixed.

Never had problems feeding inverters with this power, but we also only use a fuel gen for a backup source of power to recharge the battery-bank, when solar isn't solar'ing that day (or week). This load is in the sweet spot of gen's output. No variable loads, no light loads, no heavy loads ... just a steady charging function that is just right for the gen's wattage/operation.

 

[dcg9381]

So you sell an off grid inverter, with an ac input, removed the gen settings from the manual, but show a grid connection? For off grid? With no UL listing. And the target audience is whom?

Lots of us who have bought them apparently.
Mobile use case is one. Sometimes grid tied.

 

[eleceng1979]

Not insulting owners, I am shaming manufactures/sellers. The OP bought an OFFGRID inverter and has a generator that conforms to the inverter manual specs. He doesn't have firmware options in his inverter as they were deleted and not allowed to change the window for generator usage due to the inverters blowing up, despite his manual stating he has them. His generator is also ETL certified and PGMA G300-2018 Compliant. The inverter has 0 certifications and meets 0 performance approvals, clearly the generator is to blame? and I am the one who draws the ire of others.

 

[saggys]

Not insulting owners, I am shaming manufactures/sellers. The OP bought an OFFGRID inverter and has a generator that conforms to the inverter manual specs. He doesn't have firmware options in his inverter as they were deleted and not allowed to change the window for generator usage due to the inverters blowing up, despite his manual stating he has them. His generator is also ETL certified and PGMA G300-2018 Compliant. The inverter has 0 certifications and meets 0 performance approvals, clearly the generator is to blame? and I am the one who draws the ire of others.

Agree, the only saving grace is the purchase price of these AIO's. I did get mine to work with a inverter generator.
Now if we could only get a Tier 1 US manufacture to design one and have it built off shore if necessary to work with almost any generator and have broader charging ranges with more control of charging set points they would have something, even if it costs twice as much.
I know there is a Tier 1 company selling them, but you can get a clone ALMOST as good for a third of the price.

 

[SoVT]

Hi,

I have the EG4 3kW inverter (3000EHV-48). It charges over 120v AC 'house' power, but not 120v AC power from a generator? Generator is a 3000w Champion, and I have the AC max charge set to 18amp on the inverter, so plenty of 'generator' juice to charge, but it refused to charge.

When I plug the inverter into 'house' AC it charges without changing any settings on the inverter. What I'm I missing?

This setup does not have solar panels connected to it, I mainly use it for a backup power during extended power outages.

Thank you.

Have you watched this?

 

[eleceng1979]

Have you watched this?

Yes, and the only thing truthful is written on his notebook prior to 3:00.

 

[James Showalter]

Yes, and the only thing truthful is written on his notebook prior to 3:00.

If you buy a company's products and don't take them at their word then is that really a "them" problem?
We would much rather you buy somebody else's unit and mess it up if you disagree. we are trying to be clear that we can't help the watt/voltage starved with poor quality genset segment of the market with our inverters.

just because other Chinese companies say it doesn't make it reliable.

 

[Mithril]

The failure rate was to high with this function. If this setting was still there I’m sure we would be talking about the unit not working at all. But like I said before you can still use a generator but it needs to be twice the size of the inverter. We are not the only ones that say this. Just because this setting is gone doesn’t mean you can’t use a generator it just needs to be within spec.

How?

In what possible way was this designed worse than the cheapest of AC-DC power supplies from aliexpress? This thread gives me 0 confidence in the design, QA, or quality of EG4 products.

I've run all sorts of things from multiple generators over the years, some very very cheap. Anything with a switching power supply "just works". RPMs drop because the fridge kicked on and HZ goes down to 55? Works. Sinewave noisy from bad power factor on an AC unit? works. Voltage drops all the way to 100v? works. Wallwarts up to 1000W power supplies for PCs. Whats given me some of the most trouble? UPSes kicking back to battery when the HZ goes to high or low. Also trying to run things from a "MSW" inverter.

I 100% believe that things connected to the AIO might misbehave on some generators (a bunch of my LED bulbs are a bit iffy/flickery), and I can see worrying about people blaming you for that. But the AIO itself?

 

[eleceng1979]

If I take your advice in the video, you state to not use 50% of the product, only as an inverter. In addition I need to purchase a separate charger and a very large, oversized generator. None of this seems to be clear as to why for the end user. I'll help you.

The reason you state this is due to your lack of PFC charging in your inverter/chargers on AC input, creating a poor power factor at the generator of roughly 0.6 while being operated at 100% current charger mode, demanding very high VARs from the genset, outside the usable range of any genset AVR, that is only rated at 0.8 PF, the industry standard. As the AVR is operated outside its design, the genset THD goes through the roof. This is why you have derated charger output trying to keep losses internally in control, which don't work and eventually overheat and it pops it semi's. Due to your charger PF being at/below 0.6 due to a poor design, you have only derated 33% of charger wattage but are absorbing at least 40% losses, hence the failure mode. You state to operate at least 2X generator than needed to make up for all of this and try keep the poor PF/poor THD in check. There is no such thing as a poor quality genset market as they are all tested/certified at the rated 0.8PF. You don't even publish charger specs for this reason. You marketed this product as offgrid with the expectation of solar heavy battery charging, not AC input, hence skipping the PFC charger due to cost and not being needed in the designers eyes. Due to such a low cost, everybody buys it for grid tie UPS, which is a problem due to no UL and heavy AC charging. In addition you have removed the ability to change the AC input parameters to essentially disallow the above scenario by creating a grid only AC qualification window on an offgrid inverter. You need the infinite AC grid to provide better PF/VARs and THD for your charger to avoid the strain. You also recommend purchasing a independent battery charger that adds PFC charging capabilities, but losing the ability to program charging profiles. Due to being a distributor stateside, you absorb warranty claims and provide support. Since you have control over software you have limited these features to help reduce failures. Did I miss anything?

I am not anti any vendor. I am pro engineering.

 

[dcg9381]

I've run all sorts of things from multiple generators over the years, some very very cheap. Anything with a switching power supply "just works". RPMs drop because the fridge kicked on and HZ goes down to 55? Works. Sinewave noisy from bad power factor on an AC unit? works. Voltage drops all the way to 100v? works. Wallwarts up to 1000W power supplies for PCs. Whats given me some of the most trouble? UPSes kicking back to battery when the HZ goes to high or low. Also trying to run things from a "MSW" inverter.

Not all things work this way. I've got load shed devices on my home that are designed to prevent what you're describing above. Below 56 Hz? Load shed. Below 110V? Load shed. Prevents bigger issues.

I expect some devices to have some sensitivity, like the UPS you mentioned. It doesn't surprise me that inverters can be sensitive.

Different devices have different sensitivies and requirements. All I ask for as a consumer is that those sensitivities / limitations are disclosed up front.

I am not anti any vendor. I am pro engineering.

I love this. But as an engineer, I want to be allowed to pick the product, price point, and efficiency that meets the needs of the application. More info is better! I do not expect a $1k product to behave like a $5k product, but I'd like to know the differences.