Hi

In our off grid setup, I sometimes use the genny to charge the batteries.

The inverter always seems to go into bypass mode when the generator is on, which is a pain as some load fluctuations can overload the generator, causing a momentary dips in the house AC, enough to cause pc's etc to reboot.

Is there a way to ensure that the inverter only uses the AC in to charge, and not to supply loads?

 

Current settings are :

OSP = SBU

CSP = S+U

I've played around with the Back To Grid

and Back To Discharge voltages, but am not getting any joy.

 

I can reduce the Max AC charging current to improve the situation, but then the genny has to run at low load for longer ,which is irritating:)

Thanks in advance!

Ian

 

 

 

 

9 hours ago, Ian said:

Is there a way to ensure that the inverter only uses the AC in to charge, and not to supply loads

Unfortunately not. The grid input, the inverter output and the load output becomes tied together once the inverter has synchronized to the grid.

The only possible solution you may find is to feed an external 48v battery charger from the gen, and  connect the  charger's dc output  to the existing battery  connection. That will set you back some money though. 

 

Thanks BRG!

Confirms my suspicion. 

Cheers

1 hour ago, Ian said:

Thanks BRG!

Confirms my suspicion. 

Cheers

Like BRG says these 48v dc chargers would be expensive, otherwise get the new Growatt 3kw 48v inverter, wire the gen to the input connect the Growatt to your batteries via a dc disconnect fuse protector and use this to charge the batteries and leave the output disconnected. Then when you need to charge the batteries close the battery disconnect switch, switch the Growatt inverter on start the generator and it will charge the batteries and you have extra pv input should you want to use it at a later stage so assist with charging during daytime. You then also have emergency standby AC power should you need it.

https://www.nextgensolar.co.za/product/3kw-48v-growatt-off-grid-inverter/