In this document and in the software modeling program, the front rigging fitting attachment locations are denoted by the number of “holes showing” in the rigging track once a rigging strap is installed. On each side of the enclosures at the front, there is a pin in the middle of the rigging track that is used to secure the Front Dollies to the enclosures. When two enclosures are linked together so that they are tight packed with the sides of the enclosures parallel, the rigging fittings are installed near the middle of the rigging track in the last available rigging cutout next to the dolly pins. In this case, there are no cutouts in the rigging track visible because the rigging fittings and the chain cover up all of the track cutouts. Hence, this position is referred to a “No Holes Showing”. For example, when two rectangular Xvls enclosures are linked together using an Xvsl linking strap, and a relative angle of 0° is required between the boxes (i.e., the boxes are tight packed with both facing straight ahead), the rigging fittings of the Xvsl linking straps are installed in the middle next to the dolly pins for “No Holes Showing”. If a relative angle of 2° is required between the two Xvls boxes, then one of the rigging fittings must be moved one cutout in the track, leaving “One Hole Showing”. If a relative angle of 4° is required, then one of the rigging fittings must be moved two cutouts in the track, leaving “Two Holes Showing”.To get the correct angle between two boxes, it does not matter on which box the holes are showing. It is even possible to achieve the correct angle with holes showing on both boxes. However, there is an advantage in always having the holes showing on the bottom box only. When standing on the ground looking up at an array, the holes showing on the bottom box are always visible. If there are holes open on the top box, they may not be visible from the ground, because the view of those holes may be obstructed by the rigging fittings. Thus, it is always best to install the rigging fittings on the top box in the
2.3 Deciding Whether to Use an Xvhg or Xvhl at the Grid
There are two pieces of rear rigging hardware and two pieces of front rigging hardware required for this purpose. The front hardware consists of two Xvsg chain assemblies. There are two types of rigging hardware, however, that may be used at the rear - either two Xvhg
The decision of whether to use the Xvhg or Xvhl for the rear rigging hardware is left to the user. The “Simplified Structural Ratings” described in Section 3.3 always assumes the worst case (i.e., the lowest rating at any angle for either the Xvhg and Xvhl). This provides for quick evaluations with the highest margin of safety, but does limit the amount of weight that can be suspended. If the the “Detailed Structural Ratings” described in Section 3.4 are used, the user will find that a greater amount of weight and greater angles are possible while maintaining a sufficient safety factor. The
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