Electro-Voice XLCi Series, Руководство по монтажу

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ELECTRO-VOICE
®
X LC i TM Rigging Manual 14
3. Rigging-Strength Ratings, Safety Factors, and
Special Safety Considerations
3.1 Working-Load Limit and Safety Factor Definitions
The structural ratings for all of the X
LC i rigging components and complete loudspeaker systems
are based on test results in which parts were stressed to failure. Manufacturers typically present
the structural-strength ratings of mechanical components or systems as either the working-load
limit (WLL) or the ultimate-break strength. Electro-Voice chooses to present the structural-load
ratings of the X
LC
i loudspeaker systems as the working-load limit. The working-load-limit rating
represents the maximum load that should ever be applied to a mechanical component or system.
THE USER SHOULD NEVER APPLY A LOAD THAT EXCEEDS THE WORKING-
LOAD LIMITS OF ANY OF THE RIGGING COMPONENTS OR COMPLETE
LOUDSPEAKER SYSTEMS DESCRIBED IN THIS MANUAL.
The working-load limits for the X
LC
i rigging components and complete loudspeaker systems
described in this manual are based on an 7:1 safety factor. The safety factor is defined as the
ratio of the ultimate-break strength divided by the working-load limit, where the ultimate-break
strength represents the force at which a part will structurally fail. For example, if a part has
working-load limit of 1,000 lb (454 kg), it would not structurally fail until a force of at least 7,000 lb
(3,629 kg) was applied, based on a 7:1 safety factor. However, the user should never apply a load
to that part that exceeds 1,000 lb (454 kg). The safety factor provides a margin of safety above
the working-load limit to accommodate normal dynamic loading and normal wear.
CAUTIONS for Working-Load Limits and Safety Factors
The working-load limits defined by the manufacturer of any rigging component should never be
exceeded. Electro-Voice bases the working-load limits of its X
LC i products on an 7:1 safety factor.
Other manufacturers of rigging components may base their working-load limits on safety factors
other than 7:1. For example, 5:1 safety factors are fairly common amongst rigging manufacturers
because many regulatory agencies call for a minimum safety factor of 5:1.
When an X LC loudspeaker system is installed where local regulations only require a safety factor
of 5:1, Electro-Voice insists that the working-load limits of the X LC i rigging never be exceeded and
that an 7:1 safety factor be maintained for the X
LC
i loudspeakers.
The user is cautioned that some local regulations may require safety factors higher than 7:1. In
that circumstance, Electro-Voice insists that the user maintain the higher safety factor as required
by the local regulations throughout the entire X
LC i installation. It is the responsibility of the user to
make sure that any X
LC
i installation meets any applicable local, state or federal safety regulations.