When To Use A Pull-Back - JBL SRX900 Series Rigging Manual

Rigging Manual

10.2 WHEN TO USE A PULL-BACK

The use of a pull-back is common when the center of gravity (CoG) of an array falls outside the footprint of the array frame. Typically, long
curved arrays with a large downtilt qualify for this condition. When this occurs, LAC-3 displays an error to indicate that the array frame
alone cannot achieve the down angle needed for the design (Example 1 - No pull-back). Using an SRX900LA PB will shift the array CoG
between the two suspension points, enabling almost any down angle to be achieved (Example 2 - With pull-back).
Example 1 - No pull-back Example 2 - With pull-back
Invalid CG Location
Center of Gravity Suspension Points Center of Gravity Suspension Points
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