Growatt tripping Generator

[Jtr042084]

I have a Growatt 3kw offgrid inverter & 1 EG4 battery, no solar or utility connection. I’m running a small inverter generator through the AC input to charge the battery until I can buy a charger.
When the battery hits 100%, the generator trips instead of continuing to run the pass-through power. This isn’t a problem, just wondering what causes it ( Im not drawing enough to cause an overload, maybe 120watt load and the final charging load is less than 400watts)
What is the inverter doing when it stops the charging of the battery to overload the generator?

 

[sunshine_eggo]

I have a Growatt 3kw offgrid inverter & 1 EG4 battery, no solar or utility connection. I’m running a small inverter generator through the AC input to charge the battery until I can buy a charger.
When the battery hits 100%, the generator trips instead of continuing to run the pass-through power. This isn’t a problem, just wondering what causes it ( Im not drawing enough to cause an overload, maybe 120watt load and the final charging load is less than 400watts)
What is the inverter doing when it stops the charging of the battery to overload the generator?

A few things to check. You need to tailor your charge current to ensure you do not pull too much current from the generator.

I don't remember the setting number, but you need to set the AC charging amps to insure you don't pull too much power from the gen.

Let's say you have a 1kW generator, 48V battery. If your AC charging amps are set to 30, and setting 13 is at 56V, then 30 * 56 = 1680W - more than the generator can handle.

Inverter priority should be SUb (solar first, then utility, then battery). If you're set to SbU, then you're telling it to switch to battery rather than keep using the utility.

 

[Bud Martin]

I have a Growatt 3kw offgrid inverter & 1 EG4 battery, no solar or utility connection. I’m running a small inverter generator through the AC input to charge the battery until I can buy a charger.
When the battery hits 100%, the generator trips instead of continuing to run the pass-through power. This isn’t a problem, just wondering what causes it ( Im not drawing enough to cause an overload, maybe 120watt load and the final charging load is less than 400watts)
What is the inverter doing when it stops the charging of the battery to overload the generator?

So the generator circuit breaker trip or the GFCI of the generator trip?
"and the final charging load is less than 400watts)"
What do you mean by that, final charging load? If the battery is full then I would not expect the charger to be drawing 400W of power, your other load is only 120W so the whole power consumption is only about 500W pulling from generator. Is this problem repeatable?

 

[Groscout]

Jtr, I have a similar/same issue. When my growatt reaches float it trips my generator gfi every time…. I called watts247 and the suggested fix was disconnect the ground wire. That didn’t fix it.

I didn’t see this as an issue because my generator isn’t automated and float is where you stop charging LFP. Who’s going to float LFP with a generator anyway?

I’m watching for a solution just in case their is one.

 

[sunshine_eggo]

Jtr, I have a similar/same issue. When my growatt reaches float it trips my generator gfi every time…. I called watts247 and the suggested fix was disconnect the ground wire. That didn’t fix it.

I didn’t see this as an issue because my generator isn’t automated and float is where you stop charging LFP. Who’s going to float LFP with a generator anyway?

I’m watching for a solution just in case their is one.

You can't even do absorption on a growatt. Let alone float.

 

[Groscout]

You can't even do absorption on a growatt. Let alone float.

This is a photo of my actual growatt manual.

 

[sunshine_eggo]

That's only for solar. AC charging is on/off at settings 12 and 13. No absorption, no float.

 

[sunshine_eggo]

In case you don't believe me, I refer you to Watts247:

Best Price 24V Growatt SPF 3000TL LVM – 3kW 120Vac Stackable Inverter 2kW MPPT Charge Controller Split Phase 120V/240V capable with two or more units – Special – Watts247 Wholesale

watts247.com

Utility/Generator Charger tips:
The generator charger is a different beast to the solar charger. (Does not utilize the Bulk and Float Charge settings)
It works on a float valve type principle. (triggers when battery voltage drops below that on setting 12 – set the voltage higher than current battery voltage to start charging right away)
Stops charging from Generator when setting 13′ s voltage is reached
Will not start charging the battery again until it drops below battery voltage – in setting 12.
Setting 01 set to SBU to activate setting 12 and 13.
Setting 02, is the Max charging current from Solar + Utility/Generator
Setting 11, is the Maximum Generator/Utility charging current @ your battery voltage (not at 120V)
Setting 14, make sure this setting includes the option to charge from utility/generator (see manual)
Note, setting Setting 11 too high for your generator may cause your generator to falter at startup, and cause the Inverter Charger to lose synchronization with the Generator (58 to 63Hz), if in doubt start small, and work your way up.
If you have any questions, feel free to reach out.

 

[Groscout]

I stood in front of my growatt and watched it go from bulk to float and trip multiple times. You can’t tell me otherwise. I watched it do the same thing several times. Would you like a video?

 

[sunshine_eggo]

Model?

 

[Bud Martin]

I stood in front of my growatt and watched it go from bulk to float and trip multiple times. You can’t tell me otherwise. I watched it do the same thing several times. Would you like a video?

So the GFCI on the generator keeps tripping even though the Ground wire of the GFCI is not connected? The GFCI monitor in imbalance of the current flow on the Hot and Neutral, so some how it is detecting imbalance of more than 5mA so it trips.
Can I see some pictures of the setup?

 

[Groscout]

Growatt SPF 3000 LVM-48p.

 

[Groscout]

If my growatt is connected to the grid it doesn’t trip when transferring to float. The generator is a whole different scenario. Also my growatt does the whole constant voltage thing/absorption but without any ability to change the adsorption settings like lail current. In other words, you set the bulk charge settings and it does what it does with adsorption. But it still happens.

 

[Bud Martin]

Which outlet has the GFCI?
Do you know if the Neutral of the Generator outlet is bonded to Ground?
How exactly did you disconnect the Ground per WATT247?

 

[sunshine_eggo]

Growatt SPF 3000 LVM-48p.

From Ian's fingers to your eyes

Growatt 48V SPF 3000TL LVM – 3kW 120Vac Stackable Inverter 4.5kW MPPT Charge Controller Split Phase 120V/240V capable with two or more units + free wifi – Watts247 Wholesale

watts247.com

Utility/Generator Charger tips:
The generator charger is a different beast to the solar charger. (Does not utilize the Bulk and Float Charge settings)
It works on a float valve type principle. (triggers when battery voltage drops below that on setting 12 – set the voltage higher than current battery voltage to start charging right away)
Stops charging from Generator when setting 13′ s voltage is reached
Will not start charging the battery again until it drops below battery voltage – in setting 12.
Setting 01 set to SBU to activate setting 12 and 13.
Setting 02, is the Max charging current from Solar + Utility/Generator
Setting 11, is the Maximum Generator/Utility charging current @ your battery voltage (not at 120V)
Setting 14, make sure this setting includes the option to charge from utility/generator (see manual)
Note, setting Setting 11 too high for your generator may cause your generator to falter at startup, and cause the Inverter Charger to lose synchronization with the Generator (58 to 63Hz), if in doubt start small, and work your way up.
If you have any questions, feel free to reach out.

This is a well known annoyance with these chargers. Regardless of what you're seeing on the display, it's behaving as described above.

Ask Ian.

 

[Bud Martin]

If my growatt is connected to the grid it doesn’t trip when transferring to float. The generator is a whole different scenario. Also my growatt does the whole constant voltage thing/absorption but without any ability to change the adsorption settings like lail current. In other words, you set the bulk charge settings and it does what it does with adsorption. But it still happens.

Is the power from the utility to GroWatt going through the utility GFCI outlet or just plain AC outlet?

 

[Groscout]

Is the power from the utility to GroWatt going through the utility GFCI outlet or just plain AC outlet?

Plain 30 amp 110v no gfci.

 

[Bud Martin]

Plain 30 amp 110v no gfci.

So there is nothing trip since there is no GFCI, try it on the outlet with GFCI then.

 

[Groscout]

So there is nothing trip since there is no GFCI, try it on the outlet with GFCI then.

Ok sounds like a good test. But why is it only a problem when switching to float?

 

[Groscout]

Which outlet has the GFCI?
Do you know if the Neutral of the Generator outlet is bonded to Ground?

Newer generators usually are aren’t they? Bonded at the frame and gfci protected?

How exactly did you disconnect the Ground per WATT247?

Watts fix was to disconnect the ground between the growatt and generator. Simple.