Sea Tel 9711-92, Installation And Operation Manual

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Maintenance 9711-92 Ku-Band TXRX
18-2
18.2. Torque and Loctite Specifications
WARNING:
Assure that all nut and bolt assemblies are tightened according to the
tightening torque values listed below:
SAE Bolt Size Inch Pounds Metric Bolt Size Kg-cm
1/4-20 75 M6 75.3
5/l6-18 132 M8 150
3/8-16 236 M10 270
1/2-13 517 M12 430
NOTE:
All nuts and bolts should be assembled using the appropriate Loctite thread-
locker product number for the thread size of the hardware.
Loctite # Description
223 Low strength for small fasteners.
242 Medium strength
638 High strength for Motor Shafts & Sprockets.
2760 Permanent strength for up to 1” diameter fasteners.
290 Wicking, High strength for fasteners which are already
assembled.
18.3. General Maintenance
18.3.1. Balancing the Antenna
The antenna and equipment frame are balanced at the factory however, after disassembly for shipping or
maintenance, balance adjustment may be necessary. The elevation and cross-level motors have a brake
mechanism built into them, therefore,
power must be ON to release the brakes and DishScan® and
antenna drive must be OFF to balance the antenna. . Do NOT remove any of the drive belts . Balancing
is accomplished by adding or removing balance trim weights at strategic locations to keep the antenna from
falling forward/backward or side to side. The antenna system is not pendulous so 'balanced' is defined as the
antenna remaining at rest when left in any position.
The “REMOTE BALANCE” parameter (located at the end of the Remote Parameters after REMOTE TILT) of the
ACU. When enabled, Remote Balance Mode temporarily turns DishScan®, Azimuth, Elevation and Cross-
Level drive OFF. This function is required when trying to balance antenna systems that have a built-in brakes
on the elevation and cross-level motors.
Assure that Antenna power is ON and that the antenna has completed initialization.
At the ACU:
1. From the ACU - REMOTE BALANCE parameter: Enable balance mode (refer to your ACU manual).
The screen should now display “REMOTE BALANCE ON”.
At the Antenna:
2. At the Antenna: Balance the antenna with the elevation near horizon (referred to as front to back
balance)
by adding, or subtracting, small counter-weights
.
3. Then balance Cross Level axis (referred to as left-right balance)
by moving existing counter-
weights from the left to the right or from the right to the left
. Always move weight from
one location on the equipment frame to the same location on the opposite side of the equipment
frame (ie from the top left of the reflector mounting frame to the top right of the reflector
mounting frame). Do NOT add counter-weight during this step.
4. Last, balance the antenna with the elevation pointed at, or near, zenith (referred to as top to bottom
balance)
by moving existing counter-weights from the top to the bottom or from the