User manual ELECTRO-VOICE XLCI RIGGING MANUAL

[. . . ] XLCi Rigging Manual ELECTRO-VOICE® XLCiTM Rigging Manual Table of Contents Rigging-Safety Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 XLCi Rigging System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. 1 Overview of the XLCi Flying System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] The total strength of the overall enclosure; which is a function of the combined forces from all of the rigging points acting on the rigging frames and enclosure as a whole. The array designer must be aware of the working-load-limit ratings and the loads being applied to the individual rigging points and the overall enclosure. An XLCi loudspeaker system is only as strong as its weakest link. It is usually the case that one of the working-load limits will be approached sooner that the other. WHEN SUSPENDING ANY XLCi LOUDSPEAKER SYSTEM OVERHEAD, THE WORKING-LOAD LIMITS MUST NEVER BE EXCEEDED FOR EACH INDIVIDUAL RIGGING POINT, OR THE OVERALL ENCLOSURE. The forces acting on each individual rigging point and on the overall enclosures in an XLCi flying system will vary with each array configuration. Determining the forces throughout an array requires complex mathematical calculations. Electro-Voice engineers have, however, defined a set of simplified structural-rating guidelines that eliminate the need for the complex calculations for most array configurations. The interaction of the complex forces throughout arrays were analyzed to develop this set of conservative guide-lines, presented below, to enable a rigger to immediately determine on site whether or not an array is safe without having to make weight-distribution calculations. The structural-strength ratings of the individual rigging points and the overall XLCi enclosures are also presented below so that a complex structural analysis can be made for any array configuration. The reader should consult an experienced structural engineer to perform the complex structural analysis. The reader is directed to the References section of this manual for a list of rigging references (for background in general rigging practice) and mechanical engineering references (for background in structural engineering analysis). 3. 3 Simplified Structural-Rating Guidelines Electro-Voice engineers have defined a set of simplified structural-rating guidelines that will enable a rigger to immediately evaluate the safety of an XLCi system on site without having to make complex force-distribution calculations. A combination of destructive testing and computer modeling were used to analyze the complex forces throughout arrays. Conservative working-load ratings were utilized to simplify the guidelines. Therefore, array configurations other than those illustrated in these simplified guidelines may be permissible for those applications, consult section 3. 4 Complex Structural-Rating Analysis for a detailed structural analysis. The simplified structural-rating guidelines are shown in Figure 7. (Note that there is a label on the back of each flying XLCi loudspeaker enclosure that includes the graphics shown in Figure 7. ) 15 ELECTRO-VOICE® XLCiTM Rigging Manual These guidelines provide a simplified rating for typical arrays based on the: 1. Total weight of that enclosure plus all of the enclosures and rigging hung below it. Angles of the force components on the front connector bars and the rigging plates relative to the enclosures. Angles of the force components on the rear connector arms and rigging plates relative to the enclosures. Figure 7: Simplified X i Rigging-Rating Guidelines LC ELECTRO-VOICE® XLCiTM Rigging Manual 16 Figure 7 includes a graph of the working-load weight-versus-angle limit rating for the XLCi enclosures. This working-load weight limit is applicable to every enclosure in an array, and includes the weight of that enclosure plus the total weight of all enclosures and rigging hardware suspended below it. The absolute enclosure angle is the vertical angle of that enclosure, where 0° represents an upright enclosure facing straight ahead (0° elevation angle). These working-Ioad-versus-angle limits take into account the complex forces generated in the front connector bars, the rear connector bars, the rigging plates, the enclosures and the (optional) pull-up line, as a result of the complex weight distribution throughout the array. [. . . ] Building, Tower or Scaffold Supports: Prior to each use, the strength and load-bearing capabilities of the building, tower or scaffold structural supports should be evaluated and certified by a professional engineer as being adequate for supporting the intended rigging system (including the loudspeakers, grids, chain hoists and all associated hardware). Prior to each use, inspect the building, tower or scaffold structural supports for any cracks, deformation, broken welds, corrosion, missing or damaged components that could reduce the structural strength. Damaged structural supports should be replaced or repaired and recertified by a professional engineer. Never exceed the limitations or maximum recommended load for the supports. [. . . ]