Generator for charging solar batteries

[someonesomewhere]

Hello. We have 10 kW solar panels, 10 kW pylontech batteries and goodwe inverter (GW10K-ET model)We are completely off-grid, from Lithuania, our small house was built to have three-phase power. We recently bought a 7.5 kW single/three-phase gasoline generator with an AVR system. How can we connect the generator to our off-grid system to charge the batteries?

 

[HarryN]

The normal way would be to buy a battery charger that can accept the input power from your generator and charge the battery pack directly.

 

[MattMan119]

Hello. We have 10 kW solar panels, 10 kW pylontech batteries and goodwe inverter (GW10K-ET model)We are completely off-grid, from Lithuania, our small house was built to have three-phase power. We recently bought a 7.5 kW single/three-phase gasoline generator with an AVR system. How can we connect the generator to our off-grid system to charge the batteries?

What voltage? i suspect 48v and they there are two of them? (all guesses)

Does the generator only do 120v single or 240v ?

 

[400bird]

I'm not familiar with that inverter, so these are general/standard options.
Does your inverter have an AC input? If so, you could wire the generator into the grid connection and have the inverter charge the battery.
If not, as mentioned, you could run a separate/dedicated battery charger.

Does the generator only do 120v single or 240v ?

Probably neither, they mentioned 3-phase and a European country.

 

[someonesomewhere]

What voltage? i suspect 48v and they there are two of them? (all guesses)

Does the generator only do 120v single or 240v ?

It does 230V and 380V

 

[someonesomewhere]

The normal way would be to buy a battery charger that can accept the input power from your generator and charge the battery pack directly.

Could you suggest some of those chargers that could be suitable for my off grid system?

 

[someonesomewhere]

I'm not familiar with that inverter, so these are general/standard options.
Does your inverter have an AC input? If so, you could wire the generator into the grid connection and have the inverter charge the battery.
If not, as mentioned, you could run a separate/dedicated battery charger.


Probably neither, they mentioned 3-phase and a European country.

I’m not familiar with any battery charger, could you please sent a link or a photo of it? I just know that it probably needs to be three-phased, but someone told me that it’s hard to find one

 

[MattMan119]

It does 230V and 380V

I think the 230v work with the chargeverter, that is what I was getting at. You said single/3phase .. so if you can get 230v check this out might work for ya:

 

[upnorthandpersonal]

Which Pylontech batteries are you using? GW10K-ET only supports high voltage batteries, so I'm guessing HV H48050 or something?

 

[HarryN]

Could you suggest some of those chargers that could be suitable for my off grid system?

I can look if you send a link to the exact products that you have.

Or even better, if you can post the pdf manuals for us to look at.

 

[upnorthandpersonal]

I think the 230v work with the chargeverter, that is what I was getting at. You said single/3phase .. so if you can get 230v check this out might work for ya

OP is likely running a high voltage battery, so that won't work.

 

[someonesomewhere]

Which Pylontech batteries are you using? GW10K-ET only supports high voltage batteries, so I'm guessing HV H48050 or something?

I have three batteries of this model FH9637

 

[someonesomewhere]

I can look if you send a link to the exact products that you have.

Or even better, if you can post the pdf manuals for us to look at.

I can’t find the manuals, so here is the pylontech batteries model: FH9637M (I have three of them).
GoodWe GW10K-ET inverter.

 

[upnorthandpersonal]

I have three batteries of this model FH9637

Those are 96V - surprised they work with GW10K-ET... are they connected in series?

 

[upnorthandpersonal]

In any case, it won't be easy to charge this from a generator. The only thing that could possibly work is to rectify the generator output and feed it into one of the MPPT inputs (it has 2, if one is unused for solar...). You'll have to be careful to use a generator that is rated higher than the max MPPT input or you'll overload the generator. This is not something you can just quickly DIY without electrical skills though...

 

[someonesomewhere]

Those are 96V - surprised they work with GW10K-ET... are they connected in series?

Is there a problem with an inverter? The batteries are on top of each other and on top of them is the LFP lithium ion energy storage battery system

 

[upnorthandpersonal]

The inverter you use needs 180V on the battery side minimum (and can go up to 600V). A single battery of yours is 96V, so that's not enough, therefor my guess is that they are configured in series with a battery balancer to keep them all in sync.

 

[someonesomewhere]

The inverter you use needs 180V on the battery side minimum (and can go up to 600V). A single battery of yours is 96V, so that's not enough, therefor my guess is that they are configured in series with a battery balancer to keep them all in sync.

The batteries look like this:

 

[wpns]

The only way this is going to work is to hook your 380 V three phase generator into the AC input of your inverter.

 

[someonesomewhere]

The only way this is going to work is to hook your 380 V three phase generator into the AC input of your inverter.

Could you please help me find out if the inverter that I have has an AC input? GoodWe inverter, model GW10K-ET

 

[wpns]

Could you please help me find out if the inverter that I have has an AC input? GoodWe inverter, model GW10K-ET

You just posted a picture of the label from that inverter that says that it has an AC grid connection rated at 380 V three phase.

 

[someonesomewhere]

You just posted a picture of the label from that inverter that says that it has an AC grid connection rated at 380 V three phase.

Thank you! So as I understand, the electrician should connect the generator directly to the inverter and the inverter would charge the battery series?

 

[wpns]

Thank you! So as I understand, the electrician should connect the generator directly to the inverter and the inverter would charge the battery series?

That’s the only way it’s going to work. You need to read the manuals on your inverter and make sure that this will work, but it’s really the only possibility.

Your inverter can draw 15 kW from the grid, so you will need to make sure that you turn things down far enough that you won’t overload your generator.

 

[upnorthandpersonal]

Thank you! So as I understand, the electrician should connect the generator directly to the inverter and the inverter would charge the battery series?

He should use a transfer switch so that you can switch to generator input or grid input. However, keep in mind that this is a grid tie inverter, and they're very picky when it comes to the quality of the sine wave. In addition, you must prevent the solar side from trying to back-feed to your generator as if it were the grid.

 

[wpns]

He should use a transfer switch so that you can switch to generator input or grid input. However, keep in mind that this is a grid tie inverter, and they're very picky when it comes to the quality of the sine wave. In addition, you must prevent the solar side from trying to back-feed to your generator as if it were the grid.

Indeed. I’m not too sanguine about it actually working, but that’s the only way it _is_ going to work. Hence my exhortation(*) to RTFM and get the settings right. And yes, indeed, if he is on the grid, he will need a transfer switch.

Trying to charge a high voltage battery stack I don’t understand with a generator I don’t understand using an inverter I don’t understand is going to be difficult at best.

(*) For what good it’ll do, I’m not very optimistic before I’ve had my coffee.