JBL VTX Series, Manual

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VTX A 12 | Rigging Manual
8.6 EXTENSION BAR AND FRAME ORIENTATION
There are three positions available for securing the Extension Bar to the Array Frame when preparing to suspend an array. Note that the
choice of physical attachment position must come from correct selection of the attachment position in the LAC-3 prediction. The frame
orientation dictates the angle to which the top enclosure of an array should be set to achieve the proper frame-to-cabinet connections.
NORMAL
This is the standard attachment position for most suspended
array configurations. When properly configured, this position
allows for a small amount of uptilt and the greatest downtilt.
The Extension Bar hangs off the back of the Array Frame; ad-
ditional shackle points are available off the back of the array
for cable strain relief.
REVERSE EXTENSION BAR
This attachment position can be used when the LAC-3 pre-
diction indicates that more uptilt is needed to reach the de-
sired array site angle. The Array Frame remains attached to
the array in the standard position, but the Extension Bar is re-
versed. The A, B and C attachment positions can still be used
if a single-point suspended array is necessary. This config-
uration provides additional uptilt for arrays having a limited
number of cabinets.
REVERSE EXTENSION BAR + REVERSE ARRAY FRAME
When both maximum uptilt and maximum array weight sup-
port is needed, the LAC-3 prediction may determine that
this attachment configuration should be used. Reversing the
Extension Bar enables maximum uptilt, while reversing the
Array Frame allows the system to support greater weight off
the front motor point. These attributes are needed for larger
arrays that must be aimed substantially upwards, such as
long side hangs for stadiums or main hangs for tall theaters.
PIN POSITION: 10°
PIN POSITION:
10°
PIN POSITION: 0 .25°
CAUTION: Always refer to LAC-3 to determine safe Array Frame and Extension Bar orientations .