• Have you tried out dark mode?! Scroll to the bottom of any page to find a sun or moon icon to turn dark mode on or off!

diy solar

diy solar

How does a 40amp breaker power a 200amp panel

spacemancw

New Member
Joined
Apr 21, 2024
Messages
20
Location
Loomis CA
My solar panels go to a grid-tied Solar Edge 7600H and then into the main 200amp panel on a 40amp breaker.
How does that 40amp breaker then feed all the circuits in that panel?
I have a 50amp stove breaker, another 40amp breaker to an barn, 30amp to the dryer and multiple 20amp and 15amp breakers to light and outlets etc.

That's a lot for a 40amp solar breaker to feed, it it not?
 
It doesn't. It reduces the grid requirement by 30-ish amps. Where normally you'd be drawing 100 amps from the grid, now you are drawing 70 amps from the grid and 30 amps from the inverter.
 
So if I wanted to move the Solar Edge to a 125amp critical loads panel ... and then put an EG12k between the CL panel and the main panel ..... could the solar edge to to the CL panel on a 40amp breaker?


What I really am trying to find out is how I can add a battery to this system.

I have
Solar Panels > SE 7600H > 40a breaker > Main Panel.

What I think I need is

Solar Panels > SE 7600H > ?a breaker > Critical Loads Panel > EG12k > ?a breaker > Main Panel
and the gage wiring
 
In the year and a half that I had a smart meter but before I had solar I never used more than 8.6 kW from the grid- 36 amps- for any 15 minute period.

For a very small lifestyle change (I don't run the dryer when I'm using other big loads) my SolArk 12ks 37.5 amps has never bogged down. I have AC, a well pump, dehumidifier that runs all summer and an electric range, in addition too the normal loads.

While you have a 200 amp panel, you probably don't use as much as you think.
 
So if I wanted to move the Solar Edge to a 125amp critical loads panel ... and then put an EG12k between the CL panel and the main panel ..... could the solar edge to to the CL panel on a 40amp breaker?


What I really am trying to find out is how I can add a battery to this system.

I have
Solar Panels > SE 7600H > 40a breaker > Main Panel.

What I think I need is

Solar Panels > SE 7600H > ?a breaker > Critical Loads Panel > EG12k > ?a breaker > Main Panel
and the gage wiring
Honestly, trying to AC couple to a battery system is just going to cause confusion and frustration. I'd buy the EG4 12Kpv, rewire the panels into the new inverter, and add a couple of WallMount PowerPro batteries. Bog standard, easy peasy, no need to try to match the frequency shift for throttling the proprietary SolarEdge stuff, and you can probably sell the used SolarEdge parts.

Of course, the first question is what the power requirements for the critical loads panel are, and if the 33(?) amps the 12Kpv can supply are going to be enough.
 
Honestly, trying to AC couple to a battery system is just going to cause confusion and frustration. I'd buy the EG4 12Kpv, rewire the panels into the new inverter, and add a couple of WallMount PowerPro batteries. Bog standard, easy peasy, no need to try to match the frequency shift for throttling the proprietary SolarEdge stuff, and you can probably sell the used SolarEdge parts.

Of course, the first question is what the power requirements for the critical loads panel are, and if the 33(?) amps the 12Kpv can supply are going to be enough.
I believe I had previously posted this, but here it is again anyway if it can help.
Its how I added batteries to an existing SMA grid tie setup, while not having to touch the existing system. I use the existing grid tie to charge the batteries during the day, and use the batteries at night.

It required some extra wiring and a transfer switch, but that was needed to add the generator anyway.
 

Attachments

  • Schematic.jpg
    Schematic.jpg
    167.3 KB · Views: 11
My solar panels go to a grid-tied Solar Edge 7600H and then into the main 200amp panel on a 40amp breaker.
How does that 40amp breaker then feed all the circuits in that panel?
I have a 50amp stove breaker, another 40amp breaker to an barn, 30amp to the dryer and multiple 20amp and 15amp breakers to light and outlets etc.

That's a lot for a 40amp solar breaker to feed, it it not?
Grid tied systems use the utility as their battery if you took an average utility bill of 750kwh a month and divided that out per hour average it would be just over 4-amps at 240v most of your loads are intermittent. :unsure:

When your solar is producing it is fairly constant for 3 to 5 hours out of the day that can easily cover all your loads if you have a way of capturing that and utilizing it as you need it as @wpns had mentioned in post #6. ;)
 
Grid tied systems use the utility as their battery if you took an average utility bill of 750kwh a month and divided that out per hour average it would be just over 4-amps at 240v most of your loads are intermittent. :unsure:

When your solar is producing it is fairly constant for 3 to 5 hours out of the day that can easily cover all your loads if you have a way of capturing that and utilizing it as you need it as @wpns had mentioned in post #6. ;)
Always a good Idea to understand your loads before building something out.
I like the Emporia Energy solution to monitor loads up to the second so I can find amp hogs, and then graph out a month or two of daily averages to get peaks and valleys. It shows energy flow both ways, so you can also see solar generation peaks and valleys. It helped me improve output by just cutting a few tree branches that were casting some shade, but only during summer months.
 
Always a good Idea to understand your loads before building something out.
I like the Emporia Energy solution to monitor loads up to the second so I can find amp hogs, and then graph out a month or two of daily averages to get peaks and valleys. It shows energy flow both ways, so you can also see solar generation peaks and valleys. It helped me improve output by just cutting a few tree branches that were casting some shade, but only during summer months.
This is my first solar system ever I received my first shipment from Signature Solar May 20th of this year it took me exactly a one week to get my equipment up and running since then I've used 20kwh from the utility. Currently my grid interactive disconnect is turned off since being hit by the last hurricane.

This is my main system

My DIY portable solar arrays survived >5 hours of wind and debris punishment.

More pics of storm damage all vegetative and utility.

Screenshot_20241007-214412_EG4 Monitor.jpg
 

Attachments

  • 1728352430266.png
    1728352430266.png
    3 MB · Views: 5

diy solar

diy solar
Back
Top