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Generator for growatt

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kdiver58

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I built for my brother and we installed a off-grid solar system using a 3000 watt growatt all in one. Until he gets some trees moved we're going to be a little shy on power now and then and have to use a generator what's the smallest generator that someone has experience with that will work with the grow what? We tried it inexpensive harbor freight model but the AC was too dirty and the all-in-one didn't like it.. we want to run everything through the groWatt as it has cleaner power for the microwave and other electronics. . We don't want anything very big at all Thanks ..k
 
Choosing an undersized generator severely limits functionality. If you have a generator attached to the growatt, and the growatt accept its power, you are running on the generator, not the inverter, and you will overload the generator if you exceed its capacity - even if you're under the inverter's capacity.

An inverter can only be an inverter or charger, not both. With AC-in and active, it's only a charger, charging the batteries and passing through the generator AC to power loads.

Most Growatt AC chargers are also a bit odd. Learn settings 12 and 13.
 
I have the same system built for myself and have the AC input set for a low amp charge for the batteries. I often plug mine into shore power to top them off before I go boondocking with my camper. We just want to use the generator to top the batteries off so that we know we'll make it through the night and can run what we want. It'll be the same as plugging it in at home. Once he gets the trees cleared the solar panels will be plenty.
 
Xhumeka said:
What exactly happens when you try to use the harbor freight? When you say the all-in-one "didn't like it", did it work at all or just not well?
Click to expand...
It just beeped over and over and would not charge. After 1 minute I stopped as it wasn't working and I didn't want to damage anything. It did not work at all.
 
kdiver58 said:
It just beeped over and over and would not charge. After 1 minute I stopped as it wasn't working and I didn't want to damage anything. It did not work at all.
Click to expand...
Honda EU2200

Can your inverter/charger limit input current if needed? The honda will tolerate a hefty surge for a long time without popping into overload.

Of course $1000.00 for a generator is probably too big for your budget right?
 
Checkthisout said:
Honda EU2200

Can your inverter/charger limit input current if needed? The honda will tolerate a hefty surge for a long time without popping into overload.

Of course $1000.00 for a generator is probably too big for your budget right?
Click to expand...
I have MPP Solar 3048LV (3000w) for my trailer with Champion 2300w generator.

I can't limit input current BUT I can change/limit the amount of power going to charge the battery - making more current available for the trailer plugs. For example, I set the minimum 2a -> battery leaving most of the generator power available when cooking but bump this up to 10a or 20a charging when watching a movie (TV is low power).

If the overall load on the generator (battery charging + loads) OR for that matter if on a 20a circuit (instead of 25a) the overload on the power source will cause whatever the power source has to trip. For my generator - it quits. For a 20a circuit, the breaker will flip. Either way, it's not the best to overload the source power and manual action is required. So it's good to understand loads enough to avoid overloading the power source :)
 
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kdiver58 said:
It just beeped over and over and would not charge. After 1 minute I stopped as it wasn't working and I didn't want to damage anything. It did not work at all.
Click to expand...

I have yet to try attaching a gasoline generator to my Growatt 24v 3000w, but after reading your comment I tried a couple other things. First I plugged my _other_ Growatt 24v 3000w (powering my shed) into my cottage unit and obviously it worked fine and as expected - passed through the AC fine, powered existing loads and charged my batteries per my settings (I had it set to 20amps).

But then I tried using my Magnum RD2212 Inverter and I received the same issue as you - beeping over and over with no fault or error, but just not accepting shore input.

I'll have to research further about why it isn't working; my gut reaction is that it's due to the modified sine wave produced by the Magnum as opposed to the pure sine wave of the Growatt. But that doesn't explain _your_ problem as I thought gasoline generators always produced pure sine wave output??

Here are the two output specs for my inverters... Growatt likes it's own, but not the Magnum:

Magnum:

s-l640.webp


Growatt:

u9N1ZPQ.png
 
Hi
I am using Growatt SPF3500ES with LiFePo4 110Ah 54V 16S2P energy storage. I was looking for information about the possibility of connecting a gasoline generator to the Inverter. I bought a Stanley Inverter generator and tested it with Growatt Inverter. The genrator works with the Inverter without any problems, it is important to set the current limit A in setting 002 to such a value that the sum of the receivers from the Inverter output and the battery charging current does not exceed the generator power of 1750W. I made a video of the test.

the generator is only started when:
- there is no power to the grid,
- there is no sun,
- the batteries are almost empty.

I run the generator only for a short time (up to 3 hours) needed to recharge the battery. Then, the Inverter supplies the receivers, depending on the power consumption, for a period of 13 - 24 hours.
 
My XW+ reacts the same way to generator power. What I myself have found is by lowering the charging amps, the inverter will accept the cleaner incoming wattage, then I can incrementally ratchet up the watts, with the inverter still accepting it. I think you'll be best off selecting a generator that can output 2X -3X the level of power you expect to be charging the batteries at. That is, the more closely you get to the max output, the more distorted the power becomes.
 
I see this is an older Thread so perhaps no longer a problem for the OP. It did get me thinking that the issue is not so much that the small portable generator had dirty AC but more that a unloaded small AC generator might be running outside the 60 cycle (+,-) frequency limit that the Growatt inverter would accept as normal AC in. These AIO's are very similar to UPS's and auto transfer switches when it comes to operation. If the incoming AC is out of spec for frequency or voltage they want to transfer to battery operation.

You might get it all to work by putting a small load onto the generator before energizing the AIO from it. You would want to limit heavy load switching that might cause the generator to have problems maintaining 60 cycles.

If someone else has an issue they might check the generators frequency unloaded and running under a small load to see if they can get the Growatt to accept the incoming power.

Just some random musing.
 
Mattb4 said:
I see this is an older Thread so perhaps no longer a problem for the OP. It did get me thinking that the issue is not so much that the small portable generator had dirty AC but more that a unloaded small AC generator might be running outside the 60 cycle (+,-) frequency limit that the Growatt inverter would accept as normal AC in. These AIO's are very similar to UPS's and auto transfer switches when it comes to operation. If the incoming AC is out of spec for frequency or voltage they want to transfer to battery operation.

You might get it all to work by putting a small load onto the generator before energizing the AIO from it. You would want to limit heavy load switching that might cause the generator to have problems maintaining 60 cycles.

If someone else has an issue they might check the generators frequency unloaded and running under a small load to see if they can get the Growatt to accept the incoming power.

Just some random musing.
Click to expand...
Yes this was exactly my experience with an older Honda EB3500. The frequency was 62-63Hz as reported by my Growatt 12KW unit. After plugging in a halogen shop light, it slowed down just enough for the Growatt to start charging. I have since replaced it with a HF Predator 9500 inverter generator which works fine without the light.
 
Thanks for providing your experience. Power from portable generators can be a bit tricky as compared to utility supply.
 
My Growatt spf5000es’s have accepted every single thing ive ever fed them, including 65hz (ive seen it drop to 50 under load, manual says 45-65 iirc) and even a modified sine wive 120v inverter fed through an autotransformer to make 240. ? Ive also started feeding it 240, let it start charging, rapidly unplugged and replugged the power cord i was feeding it into the 120v side of said autotransformer, and had it continue operating off 120v input.

My personal experience leads me to believe the ‘reputation’ growatts have on this (which i knew nothing about) might be limited to older models. I have NO complaints about the ac input functionality other than oddball stuff noone else would care about.
 
I plan to use the EG4 30A battery charger from Signature Solar plugged into my Honda EU2000 inverter generator to charge batteries that are running low after too many cloudy days. Not sure if I will be able to keep the batteries connected to the inverter while doing this or if I will need to charge them disconnected. I have used the charger to charge the batteries at my home very well. I haven't used it at the cabin connected to the off grid system yet.
 
markaubin said:
Yes this was exactly my experience with an older Honda EB3500. The frequency was 62-63Hz as reported by my Growatt 12KW unit. After plugging in a halogen shop light, it slowed down just enough for the Growatt to start charging. I have since replaced it with a HF Predator 9500 inverter generator which works fine without the light.
Click to expand...

Why didn't you just lower the engine speed?
 
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