Rigging, Rules for suspension, Shock loading – QSC Audio WL2102-w User Manual

Page 6: Wideline working load limits and design factors

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6

Rigging

Rules for Suspension

•Correct use of all suspension hardware and components is imperative in sound system rigging and deployment.

•Always calculate suspended loads before lifting to ensure suspension components and hardware are used within their respective
load limits.

•Research local codes and regulations to fully understand the requirements for suspended loads in the venue in which the equipment
is to be suspended.

•Use only shackle holes for suspension of array.

•Be absolutely certain of the integrity of any structural member intended to support suspended loads. Hidden structural members can
have hidden structural weakness.

•Consult a professional mechanical or structural engineer licensed in the jurisdiction of the sound system installation to review, ver-
ify, and approve all attachments to the building or structure.

•Never assume anything- owner or third-party supplied suspension attachment points may not be adequate for the loads to be sus-
pended.

•Employ the services of a professional rigger for hoisting, positioning, and attaching the equipment to the supporting structure.

•Always inspect all components (enclosures, suspension brackets, pins, frames, bolts, nuts, slings, shackles, etc.) for cracks, wear,
deformation, corrosion, missing, loose, or damaged parts that could reduce the strength of the assembly before lifting. Discard any
worn, defective, or suspect parts and replace them with new appropriately load-rated parts.

Shock Loading

When a load is either moved or stopped, its static weight is magnified. Sudden movements can magnify the static weight several
times. This magnification of static weight is termed "shock loading". Shock loading poses a danger to equipment and workers. The
effects of shock loading can be instantaneous, or they may remain undetected unless the equipment is visually damaged. Avoiding
shock loading requires careful planning and knowledge of equipment, rigging, and lifting practices.

Shock loading of equipment and structures is usually confined to lifting and installation, but natural forces (winds, earthquakes) can
impose shock loads several times the static load. This is why structures and suspension equipment must be capable of supporting sev-
eral times the weight of the equipment suspended.

WideLine Working Load Limits and Design Factors

Table 1 lists the WideLine suspension components and provides Working Load Limit data at various Design Factors. The tabulated
Design Factors are for static loads only. The choice of which Design Factor to use will depend upon the jurisdiction and venue of instal-
lation, as well as the conditions of suspension. Dynamic conditions are determined by unknown, installation-specific factors and
should be referred to a Licensed Structural Engineer for clarification before proceeding with any suspension of the equipment. The data
presented is based upon the listed component weights:

Component

Weight

4:1 Design Factor

5:1 Design Factor

7:1 Design Factor

10:1 Design Factor

WL2102

70 lb (31.8 kg)

2300 lb (1040 kg)

1800 lb (836 kg)

1300 lb (597 kg)

920 lb (418 kg)

WL2102-w

83 lb (37.7 kg)

2500 lb (1130 kg)

2000 lb (909 kg)

1400 lb (649 kg)

1000 lb (455 kg)

Fly Grid

87 lb (39.5 kg)

1800 lb (794 kg)

1400 lb (636 kg)

1000 lb (455 kg)

700 lb (318 kg)

Stacking Frame

33 lb (15.0 kg)

1800 lb (794 kg)

1400 lb (636 kg)

1000 lb (455 kg)

700 lb (318 kg)

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