30kw PV Service Sizing

I admit I didn't think about voltage drop over 400ft. However if you run DC in that pipe it may be an option to just compromise on voltage drop. There was a paper in Solar Pro magazine a few years back that argued that upsizing for DC voltage drop was break-even on cost.
Yeah and, of course, the good thing about the DC run is you don't have to worry about voltage Rise on the AC side and risking inverter drop out from over voltage. That is typically my primary concern when designing a long AC run with losses kinda being secondary. With DC, just adding a panel or two may be much cheaper than big wire.
 

BackCountry

Electrician
Location
Southern California
Occupation
Licensed Electrician and General Contractor
That's a good point. We're over sized on this one anyway. I thought some more about your idea of using the service entrance wire exception, not a bad idea at all when you don't want to replace the panel. Commonly here in California, the trouble is you have a meter socket with a main disconnect integrated into one device, so there isn't any feeder to tap, because it's a straight shot from the jaws to a bus bar and to a main disconnect (at least in this case). I think my only other option here, since this is a meter main -- the panel board is separate, is to maybe use a Millbank 320 socket with two disconnects, or put a new meter socket in without a disconnect, and add a main breaker to their existing 200A panel. Always an adventure.

Fronius has a weird cell phone modem offering, doesn't look integrated. Anyone have any experience with using a cell modem for monitoring on Fronius inverters? This will be my first time using Fronius.
 

BackCountry

Electrician
Location
Southern California
Occupation
Licensed Electrician and General Contractor
Talked to Fronius this morning, no go. They don't meet the new smart grid rule 21 requirement, and won't for some time.

In my quiver, I'm showing the next highest output single phase inverter as a SolarEdge 11kw, any one know of anything else?
 

BackCountry

Electrician
Location
Southern California
Occupation
Licensed Electrician and General Contractor
I do like the 7.7’s — three of those is about the same capacity as two SolarEdge 11kw’s — and the three SMA’s would be a few hundred cheaper.

We usually are all Enphase, I’ve installed 7.7’s before, nice product. I’ve never installed SolarEdge.

Now I just need to finish the 6 permitted jobs ahead of this one!
 
I do like the 7.7’s — three of those is about the same capacity as two SolarEdge 11kw’s — and the three SMA’s would be a few hundred cheaper.

We usually are all Enphase, I’ve installed 7.7’s before, nice product. I’ve never installed SolarEdge.

Now I just need to finish the 6 permitted jobs ahead of this one!
I used to use fronius, then one of my main suppliers AEE started giving me substantially better pricing on SMA. I havnt really needed the 1000V capability and they are like a 300 premium now. The bigger sizes is kinda nice, but thats also less MPPT's. Also, I have worked on a lot of utility scale systems using string inverters, one had 72 tripowers, so I am pretty agnostic to having to install 4 inverters for a large resi ground mount.
 

BackCountry

Electrician
Location
Southern California
Occupation
Licensed Electrician and General Contractor
For sure. I will have to dig a little into the manual on linking three of them with one cell modem.

What are you doing for footings? We are all ground screws now.
 
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