ViaSat Series 8345, Руководство по установке

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Chapter 2 - Installation
b. Similarly stretch two more lengths of line between the other chosen points to
form an equilateral triangle on the reflector. Tighten the fasteners at connection
"C" for the three ribs located at the apexes of the triangle.
c. Stretch another line from one triangle apex (in the left corner of the notch) to one
of the three opposite notches included within the triangle. Where this movable
string crosses the opposite leg of the triangle, the lines should just touch each
other. If the lines more than touch, i.e., one actually displaces the other, or, if a
gap is observed between them, then the corresponding Rib must be raised or
lowered. In order to raise or lower a Rib, the attached Panel Brace must be
loosened slightly from it at connection "C". Two persons are required, one to
hold the Rib in position, and one to retighten the bolt at the Panel Brace
connection, since accuracy is critical.
d. Similarly measure and adjust the other two Ribs that fall within the same part of
the triangle.
e. Reposition the movable line at each of the other two apexes of the triangle,
similarly adjusting the opposite Ribs which fall within the corresponding sector
of the triangle.
When the above procedure has been completed, the Panel joints at the rim of the
reflector should lie in an almost perfect plane.
10. Torque all panel fasteners to 7-9 lb-ft if using a torque wrench, or 1/2 - 2/3 turn
past snug tight if no torque wrench is available. To avoid distortion of the
reflector during tightening, use the following sequence:
a. Starting at any reflector Panel, tighten each of the bolts at Location 1, the
bolts which hold the Panels to the Hub.
b. Tighten the next larger Ring of bolts and continue tightening bolts in ever-
increasing concentric circles, until the reflector is completely tight.
11. Re-check the panel curvature according to the procedure in STEP 8. Also, re-
check the stringing accuracy of the reflector, according to STEP 9, to verify that
the reflector shape was maintained during the panel screw tightening sequence.
If the reflector requires further adjustment, loosen the panel screws and
repeat STEPs 8 through 10 until the reflector aperture is flat.
Remove the reflector alignment strings.
e. Once the four main ribs are set, make up another line long enough to go
across the reflector and drape over the outside about 1 foot on either side.
Tie a 1-inch nut to each end of the line to weight it down.
f. Stretch the movable line across the reflector at a position which doesn’t
already have a line. It is not necessary to tape it because of the weights
on each end. Adjust each of the ribs beneath this line until the line just
touches the lines which form the sides of the “square”.
42S199F
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