Mr.Sparkle
Senior Member
- Location
- Jersey Shore
(G) Rod and Pipe Electrodes. The electrode shall be installed
such that at least 2.44 m (8 ft) of length is in contact
with the soil. It shall be driven to a depth of not less than
2.44 m (8 ft) except that, where rock bottom is encountered,
the electrode shall be driven at an oblique angle not
to exceed 45 degrees from the vertical or, where rock bottom
is encountered at an angle up to 45 degrees, the electrode
shall be permitted to be buried in a trench that is at
least 750 mm (30 in.) deep. The upper end of the electrode
shall be flush with or below ground level unless the aboveground
end and the grounding electrode conductor attachment
are protected against physical damage as specified in
250.10.
so the GRVAD is a fully necessary item at times.
Not if you have an Al. An Al is an acceptable replacement for a GRVAD.