Fusing for small grid tie system

I am installing a small grid-tied system, (5) 220W modules and a 1.1kW Grid-tied inverter. I was curious if anyone had experience or comments on using in-line fuses for the single PV string rather than something like a Midnite Solar MNPV3 and whether it would meet code. Installation is on the side of a building with a very clean looking install. DC disconnect is on the inverter in the electrical room of the building. DC wire is run in metal conduit from exterior to DC disconnect.

This is my first post but I use this forum for information all the time and appreciate everyone's willingness to take the time to share their knowledge.




  • BB.BB. Super Moderators, Administrators Posts: 32,008 admin
    Re: Fusing for small grid tie system

    How will the panels be installed... 5 in parallel, or 5 in series? (or is this a micro inverter installation?)

    For one or two parallel strings, you do not need any series protection fuses/breakers in the solar array side. I think you still need a DC disconnect before it goes into the building (not a code guy).

    It also, somewhat, depends on where you live. The local building department/inspectors may also have their own requirements.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Solar Expert Posts: 9,361 ✭✭✭✭✭
    Re: Fusing for small grid tie system
    BB. wrote: »
    ....It also, somewhat, depends on where you live. The local building department/inspectors may also have their own requirements...

    The DC disconnect shall be painted Puce with Endangered Tiger Orange stripes.
    The AC disconnect shall be painted with Emerald Red, with Gold Accents at the corners
    The Ground Rod shall be buried 7.9' and connnected with a fancy green & yellow stripe wire, no less than 6 gauge.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

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