diy solar

diy solar

Can I get confirmation on wiring/grounding for growatt?

griftin

New Member
Joined
Dec 5, 2021
Messages
11
Hey all! I've been slowly building out my system and though I think I have an understanding, I would love any feedback on my current focus:

So, the DC side of my growatt is complete. I'm starting to add AC connections, specifically AC out. I'm using a 24v growatt 3000watt inverter. I have the cable running from AC out through 8 awg wires into a breaker box. The breaker box has a 2 pole 30 amp breaker connected that I'm running my hot into and jumpering, neutral is going to a neutral bar. I added a ground bar (not sure I needed to) and have wired the ground to it. I added all 20 amp single pole breakers and on my first breaker, I've wired a simple outlet.

My main worry is grounding. I've seen people wire a three prong directly to these inverters and it works fine. I've obviously set it up to be properly grounded if needed, but everything I wire up in this off grid cabin will be going through this breaker box. Do I need a true ground?

I also plan to connect this to a generator from time to time. The generator is just a portable Westinghouse that I charge my small battery bank on (completely different system). I've never physically grounded the generator. Do I need to if I connect it up?

I have not turned this system on to test whether the plug works. I would prefer to hear feedback before I do any live tests.

Thanks for all the help so far everyone! PXL_20211213_180129833.jpg
 
Do I need a true ground?
A system can be left floating but I do not recommend it. If it is left floating, it can develop reasonably high potential difference with earth ground and I do not like doing that. Even if it never turns into a safety issue, it has the potential (pun intended) of damaging equipment.

From what I can tell in the picture, everything looks fine. However, have you thought about where the Neutral-Ground bond will be?
Growatt recently made a hardware change that could impact what you need to do for the N-G bond. What is the part number on the sticker on the side of the unit:
1639450212470.png

I also plan to connect this to a generator from time to time. The generator is just a portable Westinghouse that I charge my small battery bank on (completely different system). I've never physically grounded the generator. Do I need to if I connect it up?
How do you plan to do that? Will you be wiring it to the input of the Growatt? Do you know if the generator is wired with an N-G bond? (Here in the US, most small gasoline generators do NOT have an N-G bond)
 
A system can be left floating but I do not recommend it. If it is left floating, it can develop reasonably high potential difference with earth ground and I do not like doing that. Even if it never turns into a safety issue, it has the potential (pun intended) of damaging equipment.

From what I can tell in the picture, everything looks fine. However, have you thought about where the Neutral-Ground bond will be?
Growatt recently made a hardware change that could impact what you need to do for the N-G bond. What is the part number on the sticker on the side of the unit:
View attachment 75658


How do you plan to do that? Will you be wiring it to the input of the Growatt? Do you know if the generator is wired with an N-G bond? (Here in the US, most small gasoline generators do NOT have an N-G bond)
PN: SKSL00 0005302

I've watched a video where someone installed a relay and used option 24 to automatically open and close the bond. Because I'm running off a generator that also needs a ground, I would not want to bond it in less it's off the generator right?

This is honestly the hardest thing for me to figure out
 
This is honestly the hardest thing for me to figure out
Grounding is far more complex than most people realize. You may want to review the 4 resources on grounding. This is the first one and it has links to the others.


You should also take a look at this resource:

This is the page from the resource that pertains to the Growatt 3K
1639516173543.png
 
Because I'm running off a generator that also needs a ground, I would not want to bond it in less it's off the generator right?
Do you know if the generator has an internal Neutral-Ground bond?
 
Back
Top