Again we have a mix of code articles, actually almost the same ones.
250.30 Grounding Separately Derived Alternating-Current Systems.
250.30(A)(4) Grounding Electrode. The grounding electrode shall be as near as practicable to and preferably in the same area as the grounding electrode conductor connection to the system. The grounding electrode shall be the nearest one of the following:
(1) An effectively grounded structural metal member of the structure
(2) An effectively grounded metal water pipe within 1.5 m (5 ft) from the point of entrance into the building
250.104 Bonding of Piping Systems and Exposed Structural Steel.
250.104(A)(4) Separately Derived Systems. The grounded conductor of each separately derived system shall be bonded to the nearest available point of the interior metal water piping system(s) in the area served by each separately derived system. This connection shall be made at the same point on the separately derived system where the grounding electrode conductor is connected. Each bonding jumper shall be sized in accordance with Table 250.66.
Exception: A separate water piping bonding jumper shall not be required where the effectively grounded metal frame of a building or structure is used as the grounding electrode for a separately derived system and is bonded to the metallic water piping in the area served by the separately derived system.
I will be honest I have never seen anyone around here comply with 250.104(A)(4)
![[Linked Image]](https://www.electrical-contractor.net/ubb/frown.gif)
Bob
[This message has been edited by iwire (edited 03-21-2004).]
![[Linked Image]](https://www.electrical-contractor.net/ubb/smile.gif)
