JBL VTX Series, Manual

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VTX A 12 | Rigging Manual
3 - MECHANICAL LIMITS
The VTX A12 suspension system and accessories comply with the 2006/42/EC Machinery Directive and have been designed following
the guidelines of DGUV regulation 17 (BGV-C1) for a minimum safety factor of 4:1. Minimum safety factor requirements for suspended
arrays are often set by local regulations. Use JBL Line Array Calculator 3 TM software (LAC-3) to check mechanical limits and ensure
compliance with local regulations. ANSI Standard E1.8 (Entertainment Technology Loudspeaker Enclosures Intended for Overhead Sus-
pension), Section 5.3.4, specifies a minimum safety factor of 5:1. If compliance with the ANSI standard is needed, make sure that the
array design produces a minimum safety factor of 5:1.
ARRAY FRAME NOTES SAFE LIMIT MAXIMUM LIMIT
VTX A12 AF Extension Bar set to the rear position (12) A12 (24) A12
VTX A12 AF Extension Bar set to the front position (8) A12 (16) A12
VTX A12 AF Reverse Frame and Extension Bar set to the front position (12) A12 (24) A12
VTX A12 SB Suspension Bar used as an Array Frame (18) A12 (18) A12
ARRAY FRAME NOTES SAFE LIMIT MAXIMUM LIMIT
VTX A12 VT + GND Using VTX A12 VT with VTX A12 VT GND outriggers (4) A12 (6) A12
VTX A12 BP Base plate for ground stacking A12 systems (2) A12 (6) A12
3.1 SUSPENDED ARRAY LIMITS
3.2 GROUND STACK ARRAY LIMITS
TIPS:
• The VTX A12 and VTX A12W share the same weight and physical size.
• The names “VTX A12” and “VTX A12W” are used interchangeably throughout this document.
TERMINOLOGY:
Safe Limit:
The safe limit provides the number of cabinets that can be used in an array while maintaining a safety factor of 4:1 or higher.
The safety factor of an array is determined by the number of cabinets, the array shape, and the overall array angle. An array constructed
within the safe limit will always yield a safety factor greater than 4:1 regardless of array parameters and conditions. Ground-stacked ar-
rays within the safe limit are stable under normal conditions. Designs exceeding the safe limit and up to the maximum limit, are possible,
but the Line Array Calculator 3 TM software should be used to check mechanical safety for the given configuration.
Maximum Limit:
Arrays larger than the maximum limit are not allowable under any conditions.
NOTES:
• When the safe limit and maximum limit are the same, the array always produces a safety factor of 4:1 or higher.
• Safe and maximum limits are only applicable to the specified accessory (i.e. base plate or array frame). When several accessories
are combined (for example, ground-stacked arrays with a base plate and subwoofers underneath), the design should always be
evaluated and checked with LAC-3.
• LAC-3 will not allow array designs below the 4:1 minimum safety factor.