Electro-Voice XLC User Manual

Page 25

ELECTRO-VOICE

XLC

Rigging Manual

XLC-127, XLC-127+ and XLC-118 Overall Enclosure Structural-Strength Ratings

The actual strength of the XLC enclosures will depend on the complex total of the combined

forces from each of the rigging points acting on the enclosure as a whole and will vary with the

array configuration. However, for the sake of simplicity, Electro-Voice chooses to define the work-

ing-load limit of the overall enclosures as the sum total of the weight of that enclosure plus the

weight of all of the enclosures and rigging hardware suspended below. This simplified working-

load weight rating of the overall enclosures is defined as being independent of the angles of pull

on the individual rigging points. The Electro-Voice engineers have chosen to define the working-

load limits of the individual rigging points as a function of pull angle so that they take into account

any variations in enclosure strength that might occur as a function of pull angle. This approach

allows the enclosure working-load limit to be defined as independent of pull angles, making the

complex structural rating analysis easier. The overall enclosure strength ratings are identical for

the XLC-127, XLC-127+ and XLC-118, and are shown in Figure 11.

CAUTIONS for a Complex Structural Rating Analysis

WHEN APPLYING A COMPLEX STRUCTURAL RATING ANALYSIS TO ANY

XLC LOUDSPEAKER SYSTEM SUSPENDED OVERHEAD, THE USER MUST

OBEY THE FOLLOWING RULES:

1. Never exceed the front-to-back angle limits for the front button-bar assemblies on any

enclosure. Never exceed the side-to-side angle limits for the front button-bar assemblies on

any enclosure.

2. Never exceed the front-to-back angle limits for the rear swing-arm assemblies on any

enclosure. Never exceed the side-to-side angle limits for the front swing-arm assemblies on

any enclosure.

3. Always make sure that every front button bar is securely locked in the front rigging tube on

every enclosure (and grid, when applicable) before lifting overhead.

4. Always make sure that every rear swing arm is securely locked in the rigging frame with the

quick-release pins on every enclosure (and grid, when applicable) before lifting overhead.

3.5 Wind Loading

The XLC loudspeaker systems have been designed to withstand winds of up to 60 miles per hour

(96.6 kilometers per hour) if the bottom cabinet is rigidly secured. For obvious safety reasons,

Electro-Voice urges the user not to suspend any loudspeaker systems overhead outdoors when

high winds are expected. When suspending XLC loudspeaker systems outdoors, the user is

strongly encouraged to rigidly tie off the bottom cabinets in all arrays as a safety precaution

against unexpected high winds.

A pull-up grid with an attached strap may be used to secure the bottom cabinets. The tie-off

assembly must have a working-load rating of 2,000 lb (907 kg). A ratchet strap with a 2,000-lb

working-load rating must be used for the pull-up assembly.