SniperX
Solar Enthusiast
- Joined
- Apr 1, 2021
- Messages
- 359
I have a 100A main panel for the solar shed. All loads are on this but the panel is full and cannot take another breaker. I have a Growatt 12kw AIO 250V 120A and the manual says to use a 80A breaker between the inverter and the panel. Normally, you would put the breaker in the panel BUT 80A is over the 50% threshold for the panel and even if that was not a factor, the panel is full (the husband bought the panel before asking what was needed)
To complicate things, my system is off-grid. I want to power this panel either by a Honda ES7000is generator OR the Growatt 12kw (with solar and 6 EG4 48V 100A batteries) so I have an EATON 100A manual transfer switch. Right now, the main power input is wired to the generator, but I am trying to install the Growatt and I am not sure how to proceed.
Question: Since my panel is full and I am going to a transfer switch, can I put the breaker between the transfer switch and the inverter like the black arrow in the picture? I would need to put that on a rail of some sort and put a box around it, but would this be acceptable? So Growatt 12kw wired to the 80A breaker, then the breaker wired into the bottom of the transfer switch. The generator wire is pulled from the panel and wired to the top of the transfer switch and then in the middle of the transfer switch, those wires then go to the top of the fusebox for the main fuse.
The Growatt 12kw can only accept 6 AWG wire (I wish I could put 4 AWG for AC but 6 AWG is the max) and this is what is keeping me awake at night. 6 AWG is rated for around 105 A (wire rated at 90 degrees C) and they want an 80A breaker. Would this wire size be ok for 120A the Growatt could provide if maxed out? 4 AWG would be better because it is rated at 140AWG at 90C.
I have been all over the place trying to find out what to do and I am on overload and getting overwhelmed.
The fusebox photos show the red/black wire going into the main 100A breaker and that is currently the wiring for the generator plug outside the shed. That wire would move to the top of the top portion of the transfer switch and then the middle row of the transfer switch would be wired with 6 AWG (or I could use 6AWG to transfer switch from Growatt 12kw and then use 4 AWG going from the transfer switch to the panel) back to the main 100A breaker on the panel. The bottom row of the transfer switch would be for the Growatt but it has to be 6 AWG. I need to know if the 80A breaker can go to the right of the transfer switch and before the Growatt 12kw to satisfy the manual's instructions to have an AC breaker. All ground (green wires) would go to a mechanical lug which would then go back to the ground in the main panel. I have a double plug on order since that is a single one and you can only put 2 wires in on connection for those. I will change that out when it gets here.
I know generally they wire the AC input on the Growatt for a generator but we want to be able to run strictly on the generator or strictly on solar/battery, so I think the transfer switch is the solution but I am open to anything at this point.
I can buy another panel, but my transfer switch is rated at 100A and so, in order to get that 80A breaker, I would need a 200A panel, and then the 100A panel would be a sub-panel... and would the 100A transfer switch work with that? I am lost at this point. Thanks for trying to help me.
The drawing is terrible, but not too computer savvy. I have a Growatt 48120 SCC and some have suggested running the main pv array to that but do I hook that to the battery rack or does it go to the main Growatt? It is not connected to anything in the picture but I wanted to get my answers in stages so I am not frying my brain.
I also have questions about the wire size for the battery to Growatt. Manual states 3*2awg (I was going to use 4/0 but it is not rated for the same amount of amps at the 3*2AWG so wondered if 2*2/0 would work)
Manual found here for Growatt 12kw
To complicate things, my system is off-grid. I want to power this panel either by a Honda ES7000is generator OR the Growatt 12kw (with solar and 6 EG4 48V 100A batteries) so I have an EATON 100A manual transfer switch. Right now, the main power input is wired to the generator, but I am trying to install the Growatt and I am not sure how to proceed.
Question: Since my panel is full and I am going to a transfer switch, can I put the breaker between the transfer switch and the inverter like the black arrow in the picture? I would need to put that on a rail of some sort and put a box around it, but would this be acceptable? So Growatt 12kw wired to the 80A breaker, then the breaker wired into the bottom of the transfer switch. The generator wire is pulled from the panel and wired to the top of the transfer switch and then in the middle of the transfer switch, those wires then go to the top of the fusebox for the main fuse.
The Growatt 12kw can only accept 6 AWG wire (I wish I could put 4 AWG for AC but 6 AWG is the max) and this is what is keeping me awake at night. 6 AWG is rated for around 105 A (wire rated at 90 degrees C) and they want an 80A breaker. Would this wire size be ok for 120A the Growatt could provide if maxed out? 4 AWG would be better because it is rated at 140AWG at 90C.
I have been all over the place trying to find out what to do and I am on overload and getting overwhelmed.
The fusebox photos show the red/black wire going into the main 100A breaker and that is currently the wiring for the generator plug outside the shed. That wire would move to the top of the top portion of the transfer switch and then the middle row of the transfer switch would be wired with 6 AWG (or I could use 6AWG to transfer switch from Growatt 12kw and then use 4 AWG going from the transfer switch to the panel) back to the main 100A breaker on the panel. The bottom row of the transfer switch would be for the Growatt but it has to be 6 AWG. I need to know if the 80A breaker can go to the right of the transfer switch and before the Growatt 12kw to satisfy the manual's instructions to have an AC breaker. All ground (green wires) would go to a mechanical lug which would then go back to the ground in the main panel. I have a double plug on order since that is a single one and you can only put 2 wires in on connection for those. I will change that out when it gets here.
I know generally they wire the AC input on the Growatt for a generator but we want to be able to run strictly on the generator or strictly on solar/battery, so I think the transfer switch is the solution but I am open to anything at this point.
I can buy another panel, but my transfer switch is rated at 100A and so, in order to get that 80A breaker, I would need a 200A panel, and then the 100A panel would be a sub-panel... and would the 100A transfer switch work with that? I am lost at this point. Thanks for trying to help me.
The drawing is terrible, but not too computer savvy. I have a Growatt 48120 SCC and some have suggested running the main pv array to that but do I hook that to the battery rack or does it go to the main Growatt? It is not connected to anything in the picture but I wanted to get my answers in stages so I am not frying my brain.
I also have questions about the wire size for the battery to Growatt. Manual states 3*2awg (I was going to use 4/0 but it is not rated for the same amount of amps at the 3*2AWG so wondered if 2*2/0 would work)
Manual found here for Growatt 12kw
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