Growatt SPF 5000 ES Wiring for 0 Export / Need help

Mark1988

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Sep 6, 2021
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Hi,

Sorry for a completely newb question but could someone please help me find a wiring diagram for how to connect the Growatt SPF 5000 ES to Utility Grid and set it to zero export?

Thanks,
Mark
 

CCAT Racing

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Aug 22, 2021
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Hi,

Sorry for a completely newb question but could someone please help me find a wiring diagram for how to connect the Growatt SPF 5000 ES to Utility Grid and set it to zero export?

Thanks,
Mark
I have my growatt 5000es setup like you describe. Check out my diagram I posted. I am trying to get it verified, so use at your own risk. Any questions on inverter settings, let me know. I can send you what mine is set to, and what settings do.SolarWiring.jpg
 

🇺🇸🇺🇸🇺🇸

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@Mark1988 - To the best of my knowledge, the GW SPF 5000 ES has no capability to export to the grid (operate in a grid-interactive mode), so the inverter is, by nature, always zero export. See operating modes, pg 21 of the manual here. Perhaps I'm misunderstanding what you mean by zero export?

@CCAT Racing - I've had the same design iteration with the GW SPF 5000 ES, but I'm led to believe that - when in line mode (AC IN = AC OUT), since I'm assuming you're using the SEAUTO-TX-5000 midpoint autotransformer, your two non-isolating midpoint transformers will operate in parallel with the utility / pole transformer. If that's the case, I believe you'd be balancing loads potentially for other customers on the grid, which is probably not what you're intending to do. I'm not sure, but I think the only way around this is either a) to use an isolating transformer, or b) use a transfer switch to disconnect grid L1/L2.
 

Lwilliams7417

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I have another question about the ac input, do I run the neutral from the main supply to the input or is it ground, line 1 and line 2??
 

Turricon

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Ground 1 and 2. Auto transformer forms neutral and 120 legs on my sub panel thru 30 amp breaker, leg 1/2 50 amp breaker in sub. then I hooked subs neutral back to mains ground/neutral bar along with subs ground bar to mains neutral/ground bar. Ground and neutral are separate in sub , rejoin in main. 50 amp breaker was the first in line then 30 amp. seems to be working for me. I am running solar and grid pass thru no battery yet.

Some days when sub panel is loaded some and the main has 0-50 watts only I see my sense monitor showing 0 watts (I have a leach load always on at around 47 watts) and my meter runs ever so slowly backwards. Think this is due to lack of batteries installed. I'm no expert and I may not have this right, but running and looks good. I think I have it right. If someone else know I'm wrong please inform me of my error. Hope this helps a little.
 

Lwilliams7417

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Ground 1 and 2. Auto transformer forms neutral and 120 legs on my sub panel thru 30 amp breaker, leg 1/2 50 amp breaker in sub. then I hooked subs neutral back to mains ground/neutral bar along with subs ground bar to mains neutral/ground bar. Ground and neutral are separate in sub , rejoin in main. 50 amp breaker was the first in line then 30 amp. seems to be working for me. I am running solar and grid pass thru no battery yet.

Some days when sub panel is loaded some and the main has 0-50 watts only I see my sense monitor showing 0 watts (I have a leach load always on at around 47 watts) and my meter runs ever so slowly backwards. Think this is due to lack of batteries installed. I'm no expert and I may not have this right, but running and looks good. I think I have it right. If someone else know I'm wrong please inform me of my error. Hope this helps a little.
Thank you. Finally someone who made it simple. I am running 2 in parallel with an auto transformer. I haven't installed yet but plan on doing most of the wiring this week before I do the final connections to the main panel. Just going to run my heat pump, water heater and fridge on it until I get more panels and another inverter.
 

Turricon

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I don't have my sub panel ground and neutral bonded till it is in the main breaker box. I'm not quite sure if that is the right way to do it. If anyone can answer that for me I would appreciate it please.
 

Lwilliams7417

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I don't have my sub panel ground and neutral bonded till it is in the main breaker box. I'm not quite sure if that is the right way to do it. If anyone can answer that for me I would appreciate it please.
Are you running an auyo transformer for your Neutral? Either way, go ahead and bond your grounds to Neutral.
DISCLAIMER!!!! I AM NOT AN ELECTRICIAN. I AM MOT A CERTIFIED SOLAR TECHNICIAN. ANY AND ALL INFORMATION I GIVE IS AT READERS OWN RISK.
 

Desert_AIP

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I don't have my sub panel ground and neutral bonded till it is in the main breaker box. I'm not quite sure if that is the right way to do it. If anyone can answer that for me I would appreciate it please.
A subpanel on your main grid panel should not be bonded. Neutral and ground are brought across and on separate busses, if in a detached building the sub panel needs its own grounding rod, but remains unbonded.
 
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bgflyguy

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The only common connection from the grid, through the Growatt and to that secondary panel is a ground.
I think this still brings up a bunch of questions.

Do you bond neutral and ground in the secondary panel after the auto transformer?

How does the growatt handle ground, is it isolated or tied to neutral (which is l2 in the us)

If you have a grounding rod in at the secondary panel, does that create a ground loop. Does it need to be matched to the house rods?
 

bgflyguy

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If you bond the neutral from the transformer to ground and ground carries through all the way from the main panel, which bonds to neutral, doesn't that create a bond?
 

Desert_AIP

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Deleted erroneous post

There is a situation I neglected to consider that makes my original posts erroneous.
 
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Jim Lee

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I have my growatt 5000es setup like you describe. Check out my diagram I posted. I am trying to get it verified, so use at your own risk. Any questions on inverter settings, let me know. I can send you what mine is set to, and what settings do.View attachment 65543
CCat, Why do you have 2 midpoint transformers. One is all that is needed to split the 240v into two 120v. David Poz has a good you-tube explaining this. OR am I missing something. I'm new to this, but trying to learn.
 

Desert_AIP

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Each can handle 5000W total, 25A (3000W) on one leg.
If you parallel them you increase that to 10000W total and up to 50A of 120VAC on a single phase.
 

Jim Lee

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Don't most people that want an off grid converter that is grid tied because they want PV first then battery then grid then generator. Doesn't that cover all the bases. Power no matter what. I'm in the planning process and ready to purchase 30 - 395 watt panels. 2 x 6s2p and 1 x 3s2p. Each of the 3 string is wire to 1 of the 3 Growatt SPF 5000 ES inverter. 6 Li Fe EG4 Batteries connected to the inverters. The 3 inverters connected to a separate circuit box with a 50A breaker each. That breaker box set up with 1 or 2 (if safer) split phase Mid point transformers connected with 50A breakers. That breaker box is connected to my home main breaker box with a 60A or 100A breaker (not sure yet) connecting both circuit boxes. The Grid and my 19.5Kw Generac Generator pass through the 200A Transfer switch keeping the grid safe during grid outages is already installed. According to Signature Solar this is the system they want to sell me. Please explain to me why this won't work and what I need to do to make it work. I really don't want to burn my house down trying to improve it. Another question is when the grid goes down I think my generator will auto start even if I have PV or battery power. How could I control that. Any other suggestions would be appreciated, but please keep it simple if possible.
 
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SoilKulcha

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May 17, 2021
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Subpanel in a different bldg gets its own grounding rod but remains unbonded ? I'm struggling with that. I have a duplex with separate meters the inspector made me detach the ground and bring it to one main ground. So from 2 meters 2grounds TO 2meters 1 ground. Of course these 2meters share a neutral from the transformer on the pole but all the circuits and electronics are separate behind the 2 meters . Both meters feed a main panel with a bonded neutral.
Here's my point if a system behind one meter has 2 or more separate bldgs on property and the point is to protect electronics from current traveling through the ground between grounding points how is that any different ?
. The electricity does not know or respect separate structures. It only flows based on recognized principles. If you ground your pv panel racking it is preferable to go to the same ground but acceptable to have its on rod .
If the hots and the neutral travel back from the detached bldg to the main and the neutral & ground are bonded in the main why have a separate ground for each building.? Bring the ground back to the main panel also.. not arguing the code just not understanding the logic applied to the principles of electricity.
 

Desert_AIP

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Grounds serve two functions.
Dissipation of induced charge (A/C creates a moving magnetic field which induces a charge in anything metal the field passes through) and safety ground for short circuit protection.

A subpanel in a detached building is required to have its own grounding rod.
The grounding rod at the subpanel is for induced charge dissipation.
Otherwise that induced charge has to travel back along the pulled over grounding wire to the main and then to earth to be dissipated, and that carried back charge will energize the main panel case and other grounded metal chassis and conduit along the return path.

The bonding point for the safety ground function is still at the main panel.
The ground bus and neutral bus in the subpanel are not bonded.
You must bring over 4 wires from the main panel, L1, L2, N and GND.
Each is attached to it's own bus.
The bonding screw in the subpanel is discarded.
That's why you bring across 4 wires.

If you bonded at the sub panel as well, you would create a current loop and turn the ground wire pulled over to the sub panel into a current carrying conductor because it would be wired in parallel with the neutral if it was attached to the neutral at two points.

There should only be a single bonding point in the entire system.
The short circuit protection energizes the cases and conduit for a split second until the circuit breaker trips.
That's true for a single main panel as well (GFCI and AFCI operate slightly differently).

The A/C magnetic field issue is why they changed the rules for generator sub panels and require the individual neutrals for each load circuit to be brought over to the sub panel with the hots, so the phases of the magnetic fields which 180 degrees out cancel each other to limit the induced charge. Older models of generator subpanel were designed only to pigtail the hots to the backup circuits.
 
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