Harman JBL Professional VTX Series, Rigging Manual

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VTX A
6 | Rigging Manual
11.6 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 Mini
Frame alone cannot achieve the down angle needed for the design (Example 1 - No pull-back). Using a VTX A6 SB Suspension Bar as
a bottom frame will move the array CoG between the two suspension points, enabling almost any down angle to be achieved (Example
2 - With pull-back).
However, when using the motors for the two suspension points to adjust the array angle, the pick-point flexibility of the MF Mini Frame
is not needed. Using a Suspension Bar at the top and another at the bottom yields the same outcome, while saving some weight and
cost (Example 3 - Two Suspension Bars).
Center of Gravity Suspension Points
Invalid CG Location
Example 1 Example 2
Example 3
Center of Gravity Suspension Points
Center of Gravity Suspension Points