Combiner box. Overall cost and requirements.

[abelov1984]

How much does it cost to add the combiner box (on the roof) to installation. It will definitely help with splicing issue, JB's and conduit cost, and probably lower the total work-hours, I think..

Can't remember, if it's required by NEC to have the CB before going to DC-disconnects (and inverters), I thought that was optional. Correct me if I'm wrong.

Thx

[sensij]

A SolaDeck costs about $70 according to google, although it depends on the options. Installation cost shouldn't be very different than whatever you were planning. OCPD is sometimes required, sometimes not. More information is needed. Do you have an approved permit? Do what it says.

[abelov1984]

It's just a general question, just for a future.
And as I already said earlier in my posts the inspection here would not go on the roof. So we can do whatever the $&@& we want up there, so the concerns pretty much are: follow the general quality of installation, make it look nice and neat and to not break the code too bad, lower maintenance cost.


Yes, we don't start until we get our permits approved.
Thx

[abelov1984]

Do you guys know if blocking diodes come with combiner box and mounted in it?
And what's the limit of differences between each string output (voltage and current) that connected in CB, so the the whole system keeps producing power efficiently. Like two arrays on a different sides of the roof and/or with a different amount of modules connected in series as a typical example..
Thx

[foo1bar]

It's just a general question, just for a future.
And as I already said earlier in my posts the inspection here would not go on the roof. So we can do whatever the $&@& we want up there, so the concerns pretty much are: follow the general quality of installation, make it look nice and neat and to not break the code too bad,

If you aren't already hiring an electrician to do the install, you should.
It costs nothing to actually do an installation up to code if you're planning on doing a quality installation.
Regardless of whether the inspector goes on the roof or not, you should be doing an up-to-code installation for 3 reasons.
1> safety
2> insurance
3> inspections and disclosures when you sell the house

Good luck

[Amy@altE]

You won't be using blocking diodes in your system. We need more information about what you are doing to make recommendations. There are too many variables for us to correctly answer a "general question".

You will usually see a "Max string size" rating for your panel. Odds are it is 15A for a typical grid-tied panel. That's the max size breaker or fuse you can use. To accurately calculate the size needed, multiply the Isc x 1.56, round up. If you are doing grid-tied to a GT inverter, you are probably at higher voltages than most DC breakers can do (except for higher cost 60V breakers), and could make sense to use a fuse instead of a breaker. If you have more than 1 or 2 strings combined, you need over current protection (OCP). If you are using a TL inverter (transformerless), you need OCP on both plus and minus lines.

The Soladeck is great if you are on a shingled roof and are wiring through the roof. Otherwise, Midnite makes good equipment.