Andrew 9.3-Meter ESA manual Preventive Maintenance

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Operate the azimuth and elevation drives as well as the feed rotation in both the plus

and minus direction from the local control/motor drive controller at least once every three months during antenna down time. Check the mechanical limit switches provided at the end points stop the antenna and feed movement, and limit travel to prevent struc- tural interference and damage. Check the mechanical limit switches for corrosion and water entry and the arm on each feed limit switch for free movement without binding. Be certain both feed rotation limit switch arms are not distorted and ride centrally on the actuating cam to open their corresponding limit switch.

Inspect the azimuth and elevation jackscrew boots for security of attachment at both

ends, for abrasion, tears, cuts, brittleness and other damage that may expose the jackscrew to the environment (water, dust, etc.). Minor repairs can be made with RTV- 108 silicone rubber sealant.

Visually inspect the feed window for dirt and the feed, feed supports, feed window,

and reflector for distortion, foreign object damage and environmental deterioration due to ice and snow, dust, rain, hail, and high winds, etc. which may cause electrical compo- nent and/or structural deformation.

Check the cable attachment to the resolvers and to the LNA or LNB’s and enclosure

mount interface for security, the cable rouging for secure hanger attachment and the cable insulation for cuts, cracking, abrasion, and other deterioration. Check the LNA or LNB’s and the resolvers for a secure mechanical attachment. Ensure proper torquing of polarization drive gear box setscrews and appropriate tensioning of corresponding drive chain assembly, if applicable.

Check (if applicable) that the drain holes in the bottom of the enclosure are not

obstructed and there is no evidence of water accumulation. Check the enclosure doors for proper closure and that the door seals are intact, not torn, abraded or otherwise damaged. Check that all other seals are intact and if not, use a coating of RTV-108 (sili- cone rubber sealant) to seal any exposed electrical fitting, bolt hold, or other possible water entry to electrical components in order to maintain a weatherproof condition. If the enclosure is provided with a vent fan, check for free operation of the fan blade. The fan bearings are permanently lubricated; any binding, abnormal noise or vibration necessi- tates replacement of he fan assembly. Check and replace the fan filter element if it appears dirty or obstructed with dust.

Visually inspect all mechanical parts for freedom of operation with no misalignment,

binding or interference. Check all cabling for sufficient slack to prevent cable strain as well as adequate restraint to prevent abrasion or chaffing during antenna and feed movement.

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Preventive Maintenance

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Contents Meter ESA Table of Contents Introduction Meter Earth Station AntennaProprietary Data Information and Assistance Technical Customer Service CenterHow to Use This Manual Overview ContentGetting Started OverviewTool Size Quantity Recommended ToolsGetting Started Returning Equipment Step Overview Foundation Preparation Installation Procedures1b A-325 Tensioning For bolts over four diameters Tensioning StepTripod Ground Mount Assembly Azimuth Beam Step Step Support Legs Assembly Step Step 20008A Step Panning Frame Assembly Step X 3 LG mm 200031A Flatwashers Azimuth Pivot Assembly 301786 Azimuth Jack Screw Assembly Step Step Step Elevation Jackscrew Assembly Step Step Grounding Cable Attachment Step Step Installation Procedures Step Jack Tripod Assembly Step Reflector Assembly Step Step Step Step Subreflector Assembly Step Step Theodolite Assembly Installation Step Step Theodolite Leveling Step Step Theodolite Centering Step Theodolite Height Adjustment Reflector Panel Adjustment Step Installation Procedures Subreflector Adjustment Step Offset Operating Angle Top Stud Nut Adjustment Subreflector Offset Tilt Adjustment StepInstallation Procedures Step Operation Overview Acquiring a SatelliteStep Polarization at 45 degrees from Optimum Setting Maximizing Odd Transponders Subreflector Adjustment Preventive Maintenance Overview General Cleaning Electrical PartsPreventive Maintenance Antenna Preventive Maintenance Drive System Voltage Current Checks Step Step Preventive Maintenance Jackscrews/Motors Gear Motor/Housing Fill Drain Requirements Lubrication Chart High-Speed Antenna Lubrication Points Medium-Speed Antenna Lubrication Points Appendix ‘A’ Appendix ‘B’