I have a question about auxiliary ground electrodes (GEs) related to ground PV arrays. what have the solar people here done and did it protect from PV equipment failures? looks like grounding is the main concern with any solar array roof mounted or ground mount. much ink is being spilled and there are revisions in NEC that go back and forth on the subject from '04 to current that add to the confusion.
how does this video which Mike Holt discourages auxiliary GEs because it could potentially cause side strikes inside of a building from a nearby lighting strikes' ground voltage gradient align with your understanding of with NEC 690.47 for solar arrays and 250.32 for sub panels? further in NFPA 780 auxiliary GEs are required with no mention of the voltage gradient idea.
I had previously grounded my HF-start arc welding table, welder frame and the garages 8 circuit sub panel with an auxiliary GE with 2AWG ground electrode conductor (GEC) and an intersystem bond point. there is also a 6awg GEC from the 8-circuit sub panel to the main panel which, of course, has its own GE, just like 250.32 seems to show. without that extra grounding work any arc welding was knocking out my TV reception and after this it fixed the interference.
could it be because NFPA 780 has the wire outside the protected building that ground voltage gradients are not an concern? would bonding three GEs on the East, West and South side (new array would be on the south side) of the 36"x30" house with new buried GECs fix this potential "side-strike" ground voltage issue?
https://www.ul.com/wp-content/uploads/2 ... tionAG.pdf
discustion on 250.32
http://solarabcs.org/about/publications ... report.pdf