SPF Growatt 5000 ES System. Design review and suggestions

[automatikdonn]

You could also implement the neutral disconnect methods for the 240v/120v load panel if you wanted to increase your safety with this system.

I would use a manual transfer switch because I like to be around for events like this. If you want automated things it will drive up the price, but should work pretty much the same way as this setup. You can have a service side ATS put into place and then wire direct from the main service panel to AC IN on the GW5KES - so when your mains go down, the ATS takes over and kicks on the genset. The example I have provided is just for those looking for more control at a better price.

 

[uzernaam]

I'd like to remind everyone in this thread that if you have a breaker on your midpoint transformer and it trips, you will have a "lost" or "floating" neutral and your service panel will be feeding your 120V phases in series at 240V.

Depending on what you have running, your 120V appliances could be seeing 240V.

While not having the transformer on a breaker presents a small risk (sometimes a winding rubs through its insulation and contacts the case) a blown transformer is far cheaper to replace than half of your home's appliances going up in smoke.

I did manage to disassemble my transformer to have a look just for peace of mind.

Also, I went back-and-forth contemplating connecting the AC IN to my USA grid. Turns out you can just run the black and red hot legs to it without a problem, just use a breaker on your grid service panel to feed it.

Here's how I connected mine:

 

[automatikdonn]

I'd like to remind everyone in this thread that if you have a breaker on your midpoint transformer and it trips, you will have a "lost" or "floating" neutral and your service panel will be feeding your 120V phases in series at 240V.

Depending on what you have running, your 120V appliances could be seeing 240V.

While not having the transformer on a breaker presents a small risk (sometimes a winding rubs through its insulation and contacts the case) a blown transformer is far cheaper to replace than half of your home's appliances going up in smoke.

I did manage to disassemble my transformer to have a look just for peace of mind.

Also, I went back-and-forth contemplating connecting the AC IN to my USA grid. Turns out you can just run the black and red hot legs to it without a problem, just use a breaker on your grid service panel to feed it.

Here's how I connected mine:

I agree, that I why I said
"You could also implement the neutral disconnect methods for the 240v/120v load panel if you wanted to increase your safety with this system."

There is a very detailed thread on how that can be accomplished, along with real world video demos of how it could work.

Design Review - Growatt SPF 5000 ES Grid Backup & Neutral Bonding

This seems to be a very popular setup, but thus far, nobody seems to have cracked the DaVinci code of safely using a Growatt SPF 5000 ES with a SEAUTO-TX-5000 Auto-Transformer and using the AC input of the Growatt in a 'utility first' configuration. Signature Solar has posted a schematic that...

diysolarforum.com

 

[Jim Lee]

I want to make sure I am understanding your question correctly.

You want to use grid input and gen input to the growatt 5KES?
You want to use the three GW inverters to power all loads?
You want to have split phase capability?

My generator and the grid are separated with an Auto transfer switch, so they would never work together. The SPF growatt 5000 ES advertises quote, "The 5000ES can work with or without batteries and even pair with the Utility if solar is not enough to power a load". What I'm Interested in is the "Pairing with the Utility" part. I'm being told and learning that Inverters including that growatt can have Grid AC imputed into the inverter (There is an AC input into the GW) and using grid AC to work with the PV and batteries for large start up loads and to auto switch to AC when needed and back to PV or battery when available. The problem I'm having is where does the AC come from to wire into the GW AC in. My main breaker box will have a Generator Interlock kit installed which forces Grid breaker off when PV breaker is on and vice versa. So AC power can't come from the main panel or any sub panel after it to supply AC power to the growatt. I do have a solution and I'm talking to an electrician tomorrow or the next day to see if it will work.
To your second comment, yes I will use 3 GW inverters (15Kw) to power all loads. I currently have a 19.5 Generac natural gas whole house generator and it handles the the house fine. Do you think 3- 5Kw inverters won't work. Please give me your thoughts on that. Next, the split phase is done with the transformer to split the 240Vac produced by the GW into 2- 120Vac phases. Let me know what you think.

 

[Jim Lee]

I agree, that I why I said
"You could also implement the neutral disconnect methods for the 240v/120v load panel if you wanted to increase your safety with this system."

There is a very detailed thread on how that can be accomplished, along with real world video demos of how it could work.

Design Review - Growatt SPF 5000 ES Grid Backup & Neutral Bonding

This seems to be a very popular setup, but thus far, nobody seems to have cracked the DaVinci code of safely using a Growatt SPF 5000 ES with a SEAUTO-TX-5000 Auto-Transformer and using the AC input of the Growatt in a 'utility first' configuration. Signature Solar has posted a schematic that...

diysolarforum.com

What is being said on that thread has gone in circles so many times I can't even figure out what is being said that works and what doesn't work. Unless YOU plan to personally fix the problem for the followers of that thread then a final decision of what works needs to be made and simplified so a non professional can understand how to actually apply it. Just my opinion. I just want to make a PV system that works and is simple to put together for a DIY individual.

 

[Jim Lee]

I finally got it drawn up. Here is the PV ground mount the way I plan to set it up. The only way I can think to get AC to the GW "AC in" is to add 2 new panels. One to be a new main 200A panel and the other to be solar production panel only and change my original main house panel with almost all the house circuits in it to a Sub Panel with a generator Interlock kit to prevent Grid and PV power in the same box at the same time. It would also allow me to switch back to grid only easily if needed. This seems to be the only way that I can use solar 1st then batteries 2nd then have the grid pair AC with the Inverter AC if the PV or battery can't handle the load. If the grid goes down, I would use PV then Battery then the natural gas generator as a last resort. Please look at my drawings and let me know if anything is done wrong. I do realize I don't show sharing or paralleling the inverters and the wiring is basically what is connected to what and doesn't show L1, L2 or N connections. N and grounds are bonded in the Transfer switch, the 1st box after the meter. Please comment positive or negative.

 

[Sun in Lithium]

Has anyone tried turning off one of the spf 5000 slave inverters to try to cut back on idle consumption?

Does the master inverter still function normally?

 

[Jim Lee]

Has anyone tried turning off one of the spf 5000 slave inverters to try to cut back on idle consumption?

Does the master inverter still function normally?

Without knowing for sure, I think it would work minus any PV input.

 

[Sun in Lithium]

Without knowing for sure, I think it would work minus any PV input.

Thanks for weighing in.
Why do you say "minus any PV input"?

I know the lvx6048 mppt controller still works when the inverter is off.

 

[Jim Lee]

Thanks for weighing in.
Why do you say "minus any PV input"?

I know the lvx6048 mppt controller still works when the inverter is off.

I'm setting up 3 SPF Growatt 5000 ES which have 1 PV input per GW. I will have 1 Serial, paralleled string going to each "PV in" on each GW. If I shut it down, I would assume I would lose that string as well. Maybe your right and it wouldn't. I'm just a DIY'er. I'm definitely not positive.

 

[Jim Lee]

Thanks for weighing in.
Why do you say "minus any PV input"?

I know the lvx6048 mppt controller still works when the inverter is off.

Thanks, That is nice to know that if I don't need the 3rd GW for power that I could possibly turn it off and not loose any PV input and save about 70 watts/hour idle consumption. When I get mine up and running, I'll definitely try it out.

 

[Sun in Lithium]

Thanks, That is nice to know that if I don't need the 3rd GW for power that I could possibly turn it off and not loose any PV input and save about 70 watts/hour idle consumption. When I get mine up and running, I'll definitely try it out.

Yes it seems it will on page 24 off the manual. https://www.manualslib.com/manual/1715722/Growatt-Spf-5000-Es.html?page=24#manual

It says "
Note: *Standby mode: The
inverter is not turned on yet but
at this time, the inverter can
charge battery without AC
output."

But there is still no guarantee that it can be done with just one of the units in parallel.

 

[Sun in Lithium]

I just tried turning off the slave inverter. Of my two lvx6048 units in parallel. And the master inverter functions normally. Power stays on and slave boots up and reconnects when turned back on, with out any issues.

Hopefully the growatt spf 5000 es do the same.

 

[Jim Lee]

I just tried turning off the slave inverter. Of my two lvx6048 units in parallel. And the master inverter functions normally. Power stays on and slave boots up and reconnects when turned back on, with out any issues.

Hopefully the growatt spf 5000 es do the same.

That sounds GREAT to me.

 

[Jim Lee]

I just tried turning off the slave inverter. Of my two lvx6048 units in parallel. And the master inverter functions normally. Power stays on and slave boots up and reconnects when turned back on, with out any issues.

Hopefully the growatt spf 5000 es do the same.

After I have 3 Inverters I may buy a 4th. I was planning to do that as future spare parts, but I could just hook it up and turn it off if not needed and turn it on if necessary.

 

[Sun in Lithium]

I have been trying to get David Pos to confirm it works with his spf 5000 es inverters but I haven't gotten a response

After I have 3 Inverters I may buy a 4th

20 kw that's quite the system. ?

 

[Jim Lee]

Buying it now and getting 26% paid by tax write off is better than waiting for price increases or not available and no write off later.

 

[ArkRob]

I'd like to remind everyone in this thread that if you have a breaker on your midpoint transformer and it trips, you will have a "lost" or "floating" neutral and your service panel will be feeding your 120V phases in series at 240V.

Depending on what you have running, your 120V appliances could be seeing 240V.

While not having the transformer on a breaker presents a small risk (sometimes a winding rubs through its insulation and contacts the case) a blown transformer is far cheaper to replace than half of your home's appliances going up in smoke.

I did manage to disassemble my transformer to have a look just for peace of mind.

Also, I went back-and-forth contemplating connecting the AC IN to my USA grid. Turns out you can just run the black and red hot legs to it without a problem, just use a breaker on your grid service panel to feed it.

Here's how I connected mine:

This looks like a really simple way to fix the issues with grid backup on the Growatt 5000/ATF combo.

 

[Jim Lee]

I just tried turning off the slave inverter. Of my two lvx6048 units in parallel. And the master inverter functions normally. Power stays on and slave boots up and reconnects when turned back on, with out any issues.

Hopefully the growatt spf 5000 es do the same.

I saw on another thread it does work just like yours does.

 

[automatikdonn]

Jim,
I think the answer to your question is here (the video will be done processing in about 15 minutes)