Hello,

I would like some advice on wiring up my inverter. 

I have the GROWATT INVERTER 3KW off grid inverter and a 24V 200Ah battery. No Panels as yet.

I have come up with the following wiring diagram. Please let me know if it is correct, and what changes I should make.

Some things I was unsure about.

1. Having an Earth Leakage after the inverter - Is this necessary?
2. The inverter has AC IN and AC OUT as separate connections, specifically, separate Earths, but do I join the earths together? The reason I ask this is because I was advised to use a 4 core cable, and the sheath can be the earth, however this would imply a shared/combined earth from AC IN to AC OUT. I have not shown this in the diagram though
3. For all the New breakers - Do I go one size up or one size down if I cannot find the correct Amps
   1. 2 Pole AC CB - 32A
   2. 1 Pole DC CB - 164A
   3. ELB - 32A 

Thank you for assisting!

I would put a switching contactor feeding from AC In to physically bypass the inverter in case of overload/fault/repairs, etc...Wire the switch bobines (windings) to default on inverter as priority, but this way if you need to take it out of line for any reason you will automatically get bypassed/switched to direct AC feeding your grid. 

I'm also personally not a an of tying components of my solar system to my main ground. I have separate grounding rods for inverter/panels/panel chassis and SPDs in the system. 

Edited January 18, 20233 yr by mafiose13

44 minutes ago, mafiose13 said:

I would put a switching contactor feeding from AC In to physically bypass...

That is a great idea. I did not think about if I needed to do any maintenance on the Inverter side, then I can move the essentials temporarily to the grid. Thank you.

 

Edit. I noticed that I can also use an AC change over switch. Are there benefits of using one over the other? 

Edited January 18, 20233 yr by devank1

I just checked my inverter, and the Earths on the AC IN and OUT are connected