georgestolz said:
At the risk of exposing my ignorance, what exactly is a pool pedestal and what does 250.30(A) have to do with it? Was that a typo for 250.32(A)?
Second, was
my question about 250.30(A)(7) that far off base, that it didn't even warrant an acknowledgement?
Yes 250.30(A) was a typo
It's 250.32(A)
250.32(A) & 250.30(A)(7)x1 both require an electrode for a seperately derived system. . 250.32(A) is more specific, talking about a separate building or structure. . So it's requiring separate electrodes for separate buildings even if they're part of the same separately derived system.
I'm assuming that the reason that you prefer 250.30(A)(7) is that it specifies the electrode to be "as near as practicable" the connection of the conductor to the main. . If you supply the second building according to 250.32(B)(1), you have one electrode serving both buildings with a connection at the main to a single equipment grounding system that has feeders and homeruns thruout both buildings.
I don't see 250.30(A)(7) as requiring a separate electrode at the second building.
Once you encounter a transformer, either with the one building, or supplying a second building, then you have another separately derived system and 250.30(A)(7) requires a separate electrode for that additional system.
The problem that I see with using 250.30(A)(7)x1 is that it doesn't differentiate between sections of one single separately derived system. . Since the same utility transformer that supplies the residential house service also powers the feeder to the second building / garage, 250.30(A)(7) doesn't require a separate electrode for the second building. . It only requires one electrode per separately derived system [with the exception of the supplementing requirement of 250.53(D)(2)]. . The house and the detached garage are in the same separately derived system. . One rod at the house satisfys 250.30(A)(7).
250.32(A) requires an additional rod at the garage [or other second building]. . And as we're debating, it requires an additional rod at additional "structures" that don't fall under the exception.
A pool pedestal is a free standing support for pool equipment. . According to the NEC definitions, it's also a "structure". . It could be a 4x4 post or posts or metal post(s) with or without cross pieces and backboards for mounting equipment.
They are very common in northern Ohio and usually have a service plug built right into the enclosure with all of the other pool electrical. . I've never seen this all-in-one type supplied with fewer than 3 circuits and usually has a 240volt 2pole breaker included. . It doesn't fall under 250.32(A)x which only eliminates the electrode requirement for one circuit and multiwire circuits.
David
