ANSI NEMA GR 1-2017 pdf free download – Ground Rod Electrodes and Ground Rod Electrode Couplings.
2.7 Adhesion
2.7.1 Test Method
An 1 8 in. length of ground rod electrode with one end cut to a 45 degree point shall be driven between two steel clamping plates or the jaws of a vise set 0.04 in. less than the diameter of the ground rod electrode, so as to shear off sufficient metal to expose the bond between the copper and the ground rod
electrode.
2.7.2 Evaluation of Adhesion
There shall be no evidence of separation of the copper and the steel core.
2.8 Ductility
2.8.1 Test Method
At room temperature (25º ±5ºC), a length of ground rod electrode shall be rigidly held in a clamp or vise and the free end bent by applying a force normal to the ground rod electrode at a distance from the clamping device equal to 40 times the ground rod electrode diameter. The magnitude of the force and the
direction of application shall be such that the ground rod electrode is permanently bent through a 30 degree angle.
2.8.2 Evaluation of Ductility
Upon visual inspection with no magnification, there shall be no evidence of cracking of the copper.
2.9 Finish
The surface of a ground rod electrode shall be smooth and free from blisters, slivers, and other types of
projections.
2.10 Straightness
The deviation from straight for any ground rod electrode shall be determined and evaluated in accordance with the following:
2.10.1 Test Method
The selected ground rod electrode shall be supported by two “V” blocks, with a dial feeler gage located at the mid-point of the “V” blocks in accordance with Figure 2-3. While rotating the ground rod electrode by hand, the maximum and minimum readings shall be recorded. The readings are then subtracted for the total deviation. The average deviation from straight for the length of the ground rod electrode located between the “V” blocks is determined by the following formula:
2.10.2 Evaluation of Straightness
Straightness of the ground rod electrode shall not vary more than 6.4 mm (0.25 in.) in. 1 .5 m (5 ft.).
2.11 Markings
A ground rod electrode shall be permanently and legibly marked with the manufacturer’s identification and the catalog or equivalent designation, within 305 mm (1 2 in.) of the driving end of the ground rod electrode.
3.1 Steel Core Properties Upon inspection of the steel core, there shall be minimal signs of pitting and erosion. There shall be no gashes or cracks that protrude slivers from the surface of the ground rod electrode. The steel core, when tested in accordance with ASTM A370, shall have a tensile strength of not less than 552 MPa (80,000 PSI) and a Rockwell hardness of no less than B80.
3.2 Zinc Coating
3.2.1 Coating Method All ground rod electrodes manufactured in accordance with this section shall be coated utilizing a method in accordance with applicable ASTM standards. Hot dip galvanized ground rod electrodes shall be manufactured in accordance with ASTM A1 23 or ASTM A1 53.
3.2.2 Thickness The zinc deposit thickness shall not be less than 0.099 mm (0.0039 in.) for an ASTM A1 23 ground rod electrode or 0.086 mm (0.0034 in.) for an ASTM A1 53 ground rod electrode.
3.2.3 Measurement The measurement for zinc thickness shall be made with a properly calibrated eddy-current (electromagnetic) device. The device shall be used in accordance with the manufacturer’s instructions, and by following the standard practice for measuring coating thickness described in ASTM E376.
3.3 Length Ground rod electrodes shall have a minimum total length of 2.44 m (8 ft.). They shall have a length as specified with a –0 tolerance.ANSI NEMA GR 1 pdf download.