Installling grounding system

Water should be applied from a distance. Avoid moisture and contaminants in mold and materials being welded. Contact between hot molten metal and moisture or contaminants may result in spewing of hot material. Base material thickness must be sufficient for the size and type of connection being made to prevent melt-through and leakage of hot molten metal. Applications or conditions may exist which require special considerations.

The mould crucible with suitable size shall be used for exothermic welding. The following procedures shall be followed before conducting the exothermic welding. Ensure that the copper cable is straight not wavy so that it fits nicely into the exothermic mould prior to the exothermic welding.

Ensure that the earth pit is free from dirt and rubbish. Down conductor for air terminal ESE type shall be connected to earthing rods to ensure direct connection to earth of any stroke current before interconnection with the general Grounding System. All joints shall be according to shop drawing.

The Grounding and Lightning Protection System shall be given a visual inspection by the Engineer during the installation. The Contractor should not allow any backfilling of trenches or pits where these systems are installed before inspection by the Engineer and the appropriate documents are signed.

After performing, works shall be inspected. Inspection of lightning should be included two steps: check underground system and general. For equipment fitted inside structural work or fix underground shall be checked and inspect before backfilling. Grounding rods shall be tested for ground resistance value before any wire is connected. The test shall be performed in normal dry weather, not less than 48 hours after rainfall.

Ground resistance shall also be measured for each piece of equipment to the ground electrode. Testing shall be with a portable ground testing megger for each ground or group of grounds. The instrument shall be equipped with ammeter reading directly in Ohms or fractions thereof to indicate the ground value of the electrode under test. The minimum resistance based on the allowable capacity of the conductor shall be as indicated in the following table:.

The earth resistance shall be measured either soil resistivity testing or earth resistance testing method. The test instrument is used Mega Digital Earth Tester. General Contractors. Code Consultants. Sign Up. Upgrade to Premium. Code calculators: Code Calculators automatically generates a detailed list of requirements.

Sign in. P Add Comment. A Rod, Pipe, and Plate Electrodes. Rod, pipe, and plate electrodes shall meet the requirements of If practicable, rod, pipe, and plate electrodes shall be embedded below permanent moisture level.

Rod, pipe, and plate electrodes shall be free from nonconductive coatings such as paint or enamel. A single rod, pipe, or plate electrode shall be supplemented by an additional electrode of a type specified in The supplemental electrode shall be permitted to be bonded to one of the following: Rod, pipe, or plate electrode Grounding electrode conductor Grounded service -entrance conductor Nonflexible grounded service raceway Any grounded service enclosure Exception: If a single rod, pipe, or plate grounding electrode has a resistance to earth of 25 ohms or less, the supplemental electrode shall not be required.

If multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1. The electrode shall be installed such that at least 2.

It shall be driven to a depth of not less than 2. 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 Plate electrodes shall be installed not less than mm 30 in.

B Electrode Spacing. Where more than one of the electrodes of the type specified in Two or more grounding electrodes that are bonded together shall be considered a single grounding electrode system.