Grounding requirements for PV Carport Structures Ground mount & Parking garage rooftop

[Power2engineer]

Trying to find answer to NEC requirement for Solar PV carport PV structure grounding & bonding.
NEC 690.47 (A) Building or Structures supporting a PV Array shall have a grounding electrode system installed in accordance with Part III of Article 250.

PV array EGC shall be connected to the grounding electrode system of the building or structure supporting the PV array in accordance with Part VII of article 250. This connection shall be in addition to any other equipment grounding conductor requirements in 690.43(C). The PV array EGC shall be sized in accordance with 690.45.

My questions.

1. Minimum number of canopy (structure) columns required to be grounded using ground rods bonded with grounding conductor to canopy columns?

2. In a Parking lot with multiple Canopy structure should the grounding of each canopy structure be tied together using a bare copper ground wire in the trench? How is this ground wire sized?

3. Is it necessary to tie these Canopy structure grounds to building ground grid (ground loop)?

4. What are the differences in grounding requirements for ground mounted canopy vs garage roof top canopy structure?

5. What are lightning protection requirements for Carport structures?

 

[jaggedben]

A general note on your post..
If you believe that lightning protection is important for your project, I suggest you contact a qualified designer of lightning protection systems. NEC requirements don't address this danger and in some cases possibly could hurt, rather than help. Aside from lightning protection, in my opinion, most of your questions are irrelevant and unnecessary for any other purpose.

Specific responses below.

Trying to find answer to NEC requirement for Solar PV carport PV structure grounding & bonding.
NEC 690.47 (A) Building or Structures supporting a PV Array shall have a grounding electrode system installed in accordance with Part III of Article 250.

PV array EGC shall be connected to the grounding electrode system of the building or structure supporting the PV array in accordance with Part VII of article 250. This connection shall be in addition to any other equipment grounding conductor requirements in 690.43(C). The PV array EGC shall be sized in accordance with 690.45.

My questions.

1. Minimum number of canopy (structure) columns required to be grounded using ground rods bonded with grounding conductor to canopy columns?

Structural steel should be bonded as in 250.104(C). There is no minimum number of columns that figures into anything. If one or more of your columns are deep enough in the ground per 250.52(A)(2), then you don't need rods at all.

2. In a Parking lot with multiple Canopy structure should the grounding of each canopy structure be tied together using a bare copper ground wire in the trench? How is this ground wire sized?

Other than EGCs that would be running between each canopy and the point of supply, there is no such requirement.

3. Is it necessary to tie these Canopy structure grounds to building ground grid (ground loop)?

See previous question. Other than the EGC for whatever circuit(s) go to each canopy, there is no such requirement.

4. What are the differences in grounding requirements for ground mounted canopy vs garage roof top canopy structure?

None.

5. What are lightning protection requirements for Carport structures?

None in the NEC. See comment at top.

 

[tom baker]

Good answers from jaggedben
Question for you.
-do these canopies have electrical power?
- if so is it a single branch circuit, multiwire branch circuit or a feeder to a panel board?