Electrical codes

Do most city electrical codes require a junction box under each panel?

Thanks.

Comments

  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Electrical codes
    sundownr wrote: »
    Do most city electrical codes require a junction box under each panel?

    Thanks.
    I'm not sure what you are asking. Every PV module has a junction box on the back. Strings of modules in a non-microinverter system are daisy chained with their integral conductors, and strings may be (with some inverters, and depending on string count, and as long as wiring does not enter a building) home run to an inverter with no other junction boxes.
  • TnAndyTnAndy Solar Expert Posts: 249 ✭✭✭✭✭
    Re: Electrical codes

    I doubt most cities have even begun to address solar.
    When the inspector for our local county system came to look at mine, I could tell he didn't have a clue what he was looking at.

    His only concern was a disconnect near the new meter base ( they meter solar input separate here ) so they could cut out the solar side should that become necessary.
  • sundownrsundownr Solar Expert Posts: 25
    Re: Electrical codes
    TnAndy wrote: »
    I doubt most cities have even begun to address solar.
    When the inspector for our local county system came to look at mine, I could tell he didn't have a clue what he was looking at.

    His only concern was a disconnect near the new meter base ( they meter solar input separate here ) so they could cut out the solar side should that become necessary.

    I have no doubt many city/county inspectors lack solar knowledge... so this was a good answer. Thanks.
  • sundownrsundownr Solar Expert Posts: 25
    Re: Electrical codes
    ggunn wrote: »
    I'm not sure what you are asking. Every PV module has a junction box on the back. Strings of modules in a non-microinverter system are daisy chained with their integral conductors, and strings may be (with some inverters, and depending on string count, and as long as wiring does not enter a building) home run to an inverter with no other junction boxes.

    I do have an old solar panel with only wires, no junction box, on back of panel and I wanted to use this panel. This is why I asked if new codes require enclosed wiring (i.e. junction box) on all panels.

    My real problem is second guessing what my city/county codes require... so I will ask for these codes from my city/county. I was also curious if anybody was ever challenged by an inspector on solar wiring and what they were challenged for.

    Thanks.
  • BB.BB. Super Moderators, Administrators Posts: 32,008 admin
    Re: Electrical codes

    If it is a really old panel--It may not be rated for 600 VAC operation (hipot) which is required for virtually all Grid Tied systems (micro inverter may not require it--but they probably will not be UL/NRTL approved either--also needed for a grid tied/inspected installation)... Many of the older panels are only rated for ~70 VDC maximum (battery system voltage).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Electrical codes

    in addition to what bb said many small cheap panels have no use or need for either a j box or any certifications because they weren't meant for the bigger applications we normally see and discuss. bb is right that many older pvs are like that, but i am sure some of these little ones meant to charge up aa batteries, cell phones, etc don't have the j boxes either as it adds an unnecessary expense, step, and size to the little panels.
  • System2System2 Posts: 6,290 admin
    Re: Electrical codes

    I think it makes sense to have a j box
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