Andrew OM24SNG-RC manual Maintenance, General Introduction Antenna Drive System Cable Inspection

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Maintenance

General

Introduction

Antenna Drive

System Cable

Inspection

The antenna and feed boom/reflector assembly incorporates self lubricating bearing assemblies throughout its construction, eliminating the need for any additional lubrication for the life of the antenna.

The feed system is factory precision aligned for optimum performance, moving or reposi- tioning feed system will only reduce performance capabilities. Do not move the feed sys- tem.

The polarization drive system does not require any periodic maintenance; however replacement of the polarization drive chain may be necessary after extended use (usual- ly several years).

Periodic maintenance of the Roto-Lok®drive normally requires only visual inspection for misalignment or damaged cables. In the event that a cable(s) may require replacement, the drive design incorporates sufficient clearance between the capstan and drum, allow- ing removal and installation of individual cables. In the event the drive has become dis- abled due to broken/tangled cables and cannot be driven safety to a stow/repair posi- tion, the margin of safety in the drive design, will allow for a cable(s) to be removed to enable the drive to be rotated to a safe stow/repair position for cable replacement. Operation with less than the total number of cables is not recommended as normal oper- ational mode, however the drive will function with reduced stiffness temporarily while awaiting replacement cable installation.

Drive cables should be periodically checked for cable misalignment or visible damage that might lead to broken wires and or tangled cables. Look for frayed/broken cable wires that might occur due to normal wear after extended lifetime, or through contact with foreign objects, such as hand tools during servicing of the antenna. In the event of frayed/broken wires are discovered, they should be replaced as soon as possible to pre- vent damage to neighboring cable assemblies.

Check cables every four weeks for the first six months of operation (cable tension, frayed/broken wires). Thereafter, monitor cables biannually. For continuous use of anten- na drive system, shorten the above recommended periodic interval by one half.

The rated capacity/stiffness of the Roto-Lok®drive system is directly related to tension within the cables configuring the azimuth and elevation drive system. Proper cable ten- sion is essential for the antenna drive system to perform as specified. How to verify and maintain proper cable tension is considered in the following discussion.

CAUTION!

Do Not Over Tension the Cable When Tightening the Cable Tension Adjusting Nuts. It is Possible to Break a Cable With the Mechanical Advantage of the Threaded End!

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Maintenance

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Contents Meter SNG Table of Contents Purpose Proprietary Data Information and Assistance IntroductionCall From Telephone Fax Customer Service CenterHour Technical Assistance Call From Call To Telephone FaxKeep Away From Live Circuits Safety SummaryDo Not Service Or Adjust Alone ESD PrecautionAntenna DescriptionGeneral Introduction Antenna Drive System Cable Inspection MaintenanceCable Replacement Azimuth Rotational Limits Overhead View of Antenna Azimuth Access Port Positioned Over Cable Adjusting Nuts Azimuth Drive Cable Tension Adjustment StepAdjusting Azimuth Cable Tension Step Elevation Cable Tension Adjustment Elevation Drive Cable Tension Adjustment StepControls and Power Failure Azimuth Drive Step Emergency ProceduresBrake Release Screws Elevation Drive Step Component Replacement Brake WiresBrake Release Hardware Body Nuts Cover Brake Brake Release Weep Hole Protective Tube Brake Cover Elevation Brake Replacement 22Specifications SpecificationsAntenna Electrical Antenna Mechanical 23Specifications24Specifications Antenna DimensionsAntenna Clearance Envelope and Center of Gravity Side View 25SpecificationsView Antenna Clearance Envelope Top View