2 x 200amp panels but only 200amp meter (not 400 or 320amp)?

[BlueMarblePA]

I spoke with a solar salesman today and sent pictures of my electric panel and meter. Basically I told them I have 2 x 200amp panels. However they noted that I only have a meter for 200amp service.

I only use 15000kwh a year which fits 200amp service rather than 400amp, but they did recommend I upgrade to 400amp before submitting permits.

Just curious what the group thinks. Why would I have two panels that appear to have 200amps but my meter only allows for this?

 

[OzSolar]

You don't need a 400 amp service but that solar salesman does have monthly sales goal to meet though.

If I was in the energy analysis business ? I would start with a high level pass/fail test. 15,000 kWh/yr/ 8760 kWh/year = ~1.7 kW average load. 1700 watts / 240 volts = 7 amps is your average amp draw. By itself that doesn't mean much but as I said it's just high level analysis. However with a fair amount of confidence I can state that you don't need a 400 amp service. (here comes a bunch of Cunningham's law keyboard warriors)

Here at my place I have a 200 amp service. That service feeds one 200 amp panel, four 100 amp panels and two 60 amp panels and never have any problem.

 

[hayhayday]

400amp serice would allow up to ~100kw, unless you use all your power on one day a month, plan to charge 3-4+ evs at a time or install a dozen ac units that run at the same time 400A is most likely overkill. It seems one of your panels is full so the 2nd one may have been added simply to give more room for breakers rather than need for more overall capacity.

 

[BlueMarblePA]

Wow. You guys are very helpful! Just so I get the calculation right. 240V * 7 amps = 1680 watts. If I then multiply 1680 watts x 24 hours = 40,320 watt hours or 40.3 kwh per day. 40.3*365 = 14,716.8 kwh per year. yeah. It seems that I only need the extra electric panel for space for breakers rather than actual need.

 

[Tecnodave]

One reason that I have seen for two 200 amp panels on a single 200 amp main is that single space breakers are way cheaper than twin breakers also they have more space to dissipate heat. I have seen 20/40 (20space/40 circuit) panels that were stacked with twin breakers that were hot to touch, cheaper than a 40 space panel but reliability suffers....

 

[Quattrohead]

40.3 kwh per day. 40.3*365 = 14,716.8 kwh per year

Blah why no delete ?

 

[BlueMarblePA]

Blah why no delete ?

Sorry. I didn't understand this comment?

 

[BlueMarblePA]

You guys are giving me confidence to install my own 7.6kw Solaredge inverter system with panels to the breaker panel via loadside 40amp circuit breaker.

 

[Hedges]

Yes, 7600W inverter and 40A breaker pencils out for 120% rule, 200A panel, 200A main breaker.
You might be allowed one in each panel for twice the power.

Is there a single 200A over-current protection device for the service?
It would appear you could draw 200A + 200A = 400A, seriously overloading the meter and utility drop wires.
But I can't tell how they are connected to meter panel.

I have a 200A breaker in meter panel, which is convenient because I can turn off power and fan out to multiple boxes.

Solar Edge may not be the best choice.
We're seeing reports that bring reliability into question.
Optimizers are useful for some situations but maybe not for many. Multiple MPPT inputs, or just parallel strings, might be just as good.

Solar Edge - an installer's blog

Came across the following blog. It includes the company's installed system numbers and failure rates for SolarEdge, Fronius, Enphase. Also, information on limitations and best use of optimizers. https://www.mcelectrical.com.au/solaredge-inverter-optimiser-review/

diysolarforum.com

If you will want battery backup in the future, plan/design/price it out before buying your grid-tie system.

 

[Mike 134]

You don't need a 400 amp service but that solar salesman does have monthly sales goal to meet though.

/\ /\ /\ THIS!!!!

Upper left corner of the left panel that an inspection label?
No worries about the 2 panels as someone mentioned it's a way to get 80 circuits without using mini breakers.
Just for laughs 15,000,000 watts a year is 62,500 amps. Each day of the year is 171 amps/day. now spread that 171 over 24 hours.
See why you'll never ever overload that 200Amp feeder?

 

[Mike 134]

You guys are giving me confidence to install my own 7.6kw Solaredge inverter system with panels to the breaker panel via loadside 40amp circuit breaker.

I did my first and only solar install on my place piece of cake with Solar Edge stuff. I saw the data set of 1 or 2 people talking about issues with solar edge but that's not a large enough sampling to sway me away.
Just an FYI make sure you can join the Solar Edge site as an installer. This way you have full control of your setup plus you can commission it yourself using the set-app.

 

[BlueMarblePA]

I did my first and only solar install on my place piece of cake with Solar Edge stuff. I saw the data set of 1 or 2 people talking about issues with solar edge but that's not a large enough sampling to sway me away.
Just an FYI make sure you can join the Solar Edge site as an installer. This way you have full control of your setup plus you can commission it yourself using the set-app.

Thanks for this. I just applied to join. They said it will take three days, so I am waiting for confirmation. If I can get access as an installer, I am going to try to do this myself.

I will use greenlancer.com to get my paperwork in order.

Will I need a licensed electrician to do the final connection, or can I just do it?

 

[BlueMarblePA]

Yes, 7600W inverter and 40A breaker pencils out for 120% rule, 200A panel, 200A main breaker.
You might be allowed one in each panel for twice the power.

Is there a single 200A over-current protection device for the service?
It would appear you could draw 200A + 200A = 400A, seriously overloading the meter and utility drop wires.
But I can't tell how they are connected to meter panel.

I have a 200A breaker in meter panel, which is convenient because I can turn off power and fan out to multiple boxes.

Solar Edge may not be the best choice.
We're seeing reports that bring reliability into question.
Optimizers are useful for some situations but maybe not for many. Multiple MPPT inputs, or just parallel strings, might be just as good.

Solar Edge - an installer's blog

Came across the following blog. It includes the company's installed system numbers and failure rates for SolarEdge, Fronius, Enphase. Also, information on limitations and best use of optimizers. https://www.mcelectrical.com.au/solaredge-inverter-optimiser-review/

diysolarforum.com

If you will want battery backup in the future, plan/design/price it out before buying your grid-tie system.

I got an amazing price for 34x280 watt panels, 34 solaredge optimizers, solaredge se-7600h-us and unirac sfm infinity rail less rack system. Hence I am just trying to use this as my backbone on a southeast roof that is close to my neighbors eighty foot trees.

I want to use solark, but the price is high and I could always feed it in to the Gen input later to the solark 15k hybrid inverter if I need a battery I think.

 

[Hedges]

Consider what you would do for grid connection if you do get a hybrid. You'll want a breaker large enough for power draw, not just PV backfeed.
Perhaps that can be retrofitted later. A 200A breaker or fusible disconnect could be good. Or maybe you downsize main breaker in one panel to allow larger backfeed. But I think OCP at the meter gives you the most flexibility.

 

[BlueMarblePA]

Consider what you would do for grid connection if you do get a hybrid. You'll want a breaker large enough for power draw, not just PV backfeed.
Perhaps that can be retrofitted later. A 200A breaker or fusible disconnect could be good. Or maybe you downsize main breaker in one panel to allow larger backfeed. But I think OCP at the meter gives you the most flexibility.

I was thinking that if I do get a hybrid later, it will be a solark 15k. My understanding of how the Solark 15k works is the following. All of the grid 200Amp service feeds directly into the solark15k. In addition, you can feed it all the PV (either AC via solaredge) and DC panels. Then, coming out of the Solark 15k is 200amp directly to the main electric panel.

So my idea would be simply disconnect the AC input from the 40amp circuit breaker in the main electric panel (PV backfeed). I would redirect that to the gen-in AC coupled input of the Solark15k.

Does this make sense?

I need to learn about overcurrent protection. There is one circuit breaker at the top of both 200 amp electrical panels, and there appears to be two independent large cables going from each electric panel to the meter. I do not know how this is wired, though.

 

[Hedges]

If cable from meter splits to two 200A breakers, my concern is you could pull 400A through a 200A utility drop.
By turning off one at a time you can confirm each only switches power to its respective panel, that they aren't daisy-chained in series.

If you connect 40A PV breaker of your main panel to SolArk 200A port, that is OK but only good for 32A continuous.
You might want SolArk to provide backup to some or all of your existing loads.

I did something similar initially, with my battery inverter backfeeding an interlocked generator breaker.
Later I fed it from a tap between meter and the breaker panel (with suitable OCP on its input.)

SolArk 15k can accept 200A input, but should have 200A fuse or breaker externally.
The inverter could fail or be disconnected for service, so a bypass that can be enabled by flipping a switch or breaker would be very useful.
The 200A main breaker in my panels. can have a 125A branch circuit breaker interlocked with it, meant as generator input but can be used as bypass. (the 200A is rated for service entrance, but might be fed from SolArk in your case. The 125A is not so rated, needs another fuse or breaker between it and grid.)

 

[foggysail]

General comment on the 120% rule and 200 amp main breakers. For example, I have a Square D load center that I installed into my home when I built it years ago leading me to believe I could only have a 40 amp breaker (after deratings) to connect the solar to the panel. Later I paid greater attention to the panel itself and found it has a 225 amp rating, not 200.

The maximum buss current therefore can be (225 + (225X 0.120) ) = 225+27 = 252A. Because the main is only rated for 200 and the difference between the main breaker's 200A and the max bus current of 252, It is possible to have a solar breaker sized at 52 amperes (50A of course).

My solar installation team noticed this also and I have a 50A breaker between my 28 400W Canadian panels and the AC mains.

 

[Hedges]

I agree except for your math. Mistake is "225 x 0.12" as additional current, 27A more.
225A x 120% = 270A
You can have 70A PV breaker, and with 80% loading 56A continuous. At 240V, 13.44 kW

 

[foggysail]

I agree except for your math. Mistake is "225 x 0.12" as additional current, 27A more.
225A x 120% = 270A
You can have 70A PV breaker, and with 80% loading 56A continuous. At 240V, 13.44 kW

 

[foggysail]

Yeah.......... head ache, end stages of the flu, skip-a-dee quick typing fingers faster than brain farts and that ends is a basic scewup! Gees, embarrassment here, of course 120% of 225A is 270. What is true though, I have a 50A breaker installed for my solar.

EDIT-- I should have copied my note pad which of course had the calculations correct. Again thanks for the correction before ten others also jumped on it