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They are; a. Kamila Wehbe. Easy Write. Johnnie Little. Hamada Khamis. Muhammed Talha Qureshi. Walter Rueda. Shaikh Ahamed. BaSem GaMal. Rahul Divakaran. Ijaz Mh. Duel Time.
The coaxial cable of the antennas should be protected with a surge protective device. The metallic elements that rise above the roof should be connected to the closest down conductor. The routing of the down-conductor should be as straight as possible, following the shortest path, avoiding sharp bends or upward sections.
The bend radii should not be less than 20cm. Bent or out-of-round cable will hold the mould open and cause leeks; therefore, the cable must be straightened before clamping the mould into place. Remove any insulation before cutting to prevent insulating material becoming trapped in the strand-ends. Use a file, emery cloth or card brush to remove oxides. On tubes, clean the inside surface as well as the outside end. Remove rust and all scale with a rasp, coarse file or grinder not resin-bonded.
Galvanised surfaces may be cleaned with emery cloth to remove oxide film; it is not necessary to remove galvanising. For cast iron less than 12mm thick do not use larger than powder no.
The body of each earth pit shall as a minimum comprise shatter-proof, lightweight, polymer material with a high resistance to chemical damage from such substances as petrol, oil, diesel, bitumen etc.
Each unit shall include high ultra-violet stability, wide temperature application and earth bar facility where necessary to permit multiple earth tape connections to be made. Where these are not suitable concrete pits shall be provided.
Site Execution of Lightning Protection System All metallic projections, ducts, vent pipes, gutters, radio and television aerials, fan housings, window cleaning equipment and tracks etc, on or above the main surface of the roof structure shall be bonded to and form part of the air termination network. No joints in either the down conductor or roof conductors shall be allowed other than at air terminal, earth electrodes and terminal or test block positions.
Where it is found that the resistance to earth at any test point is in excess of 10 ohms, the length and number of earth electrodes shall be increased to the instructions of the MEP Consultant, in order to comply with the requirements of the British Standard. In addition, the resistance from the earth electrode to the nearest test clamp shall not exceed 0. The Contractor shall include ensure that at the completion of the installation to resistance to earth from each testing point does not exceed 10 ohms, the tests being carried out in accordance with BS The Contract shall include for the performance of these tests and submitting the results to the MEP Consultant.
Connections to the earth electrodes shall not be covered over with top soil without the permission of the MEP Consultant. Upon completion of the works, submit a certificate of installation to the MEP Consultant for review and approval.
The operating and Maintenance manuals shall be compete with system records to BS that includes the following items as a minimum: As installed drawings Nature of soil Earth resistivity measurement. Earth electrode resistance. Earthing and Lightning Protection. Electrical Earthing or Grounding System.
Building Protection. Lightning Protection. Electrical Substation.
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