Reality Wizard
New Member
Hi all,
I'm working with permit/design group and wanted to see y'alls take on this:
I have a 125 amp main service panel, I figured that while the inverter can only do 50amps it will be fine since I generally don't believe I use more than this on a usual basis. Also, since the grid pass through is 100 amps the 125 main service panel is actually appropriately sized as that is 125% the total load that the house will ever draw.
The design company is telling me that they think it will not quite work as it only has 50amps and I have 125 amps service, so it is only partial backup. They suggested going to a 200amps main service panel and doing a critical loads panel off that. Otherwise they say that the service will have to be derated to 100amps.
I don't see why I can't wire the inverter upstream of the main service panel but downstream of a manual transfer switch. This would theoretically allow me to usually keep the switch on the inverter for 99% of the time, but should the inverter go down I can manually switch to grid power and fix the inverter. This also allows for the inverter to handle pulling from the grid vs solar vs battery automatically.
Unless I'm seriously missing something, then the 50amps will be fine most of the time and the few times it's not the pass through will work, meaning there's no reason to do a main service panel upgrade and no reason to do these critical loads panels and such.
I am also somewhat unsure on how the battery amperage plays into this, the discharge amps being 250?
Thanks y'all!!
I'm finally getting this solar show on the road and excited to have it done lol.
Edit: Also, to be clear this is definitely for an off-grid system (don't feel like playing the electric game and don't want to help the companies), and will include batteries. I'm open to battery suggestions too! (I'm aiming for the EG4 LL-S V2 48V, but that's mostly a diff topic).
Will also include around 9kW solar is the plan (may change to 7-8kW depending).
I'm working with permit/design group and wanted to see y'alls take on this:
I have a 125 amp main service panel, I figured that while the inverter can only do 50amps it will be fine since I generally don't believe I use more than this on a usual basis. Also, since the grid pass through is 100 amps the 125 main service panel is actually appropriately sized as that is 125% the total load that the house will ever draw.
The design company is telling me that they think it will not quite work as it only has 50amps and I have 125 amps service, so it is only partial backup. They suggested going to a 200amps main service panel and doing a critical loads panel off that. Otherwise they say that the service will have to be derated to 100amps.
I don't see why I can't wire the inverter upstream of the main service panel but downstream of a manual transfer switch. This would theoretically allow me to usually keep the switch on the inverter for 99% of the time, but should the inverter go down I can manually switch to grid power and fix the inverter. This also allows for the inverter to handle pulling from the grid vs solar vs battery automatically.
Unless I'm seriously missing something, then the 50amps will be fine most of the time and the few times it's not the pass through will work, meaning there's no reason to do a main service panel upgrade and no reason to do these critical loads panels and such.
I am also somewhat unsure on how the battery amperage plays into this, the discharge amps being 250?
Thanks y'all!!
I'm finally getting this solar show on the road and excited to have it done lol.
Edit: Also, to be clear this is definitely for an off-grid system (don't feel like playing the electric game and don't want to help the companies), and will include batteries. I'm open to battery suggestions too! (I'm aiming for the EG4 LL-S V2 48V, but that's mostly a diff topic).
Will also include around 9kW solar is the plan (may change to 7-8kW depending).
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