Model 6 Motor Control Centers 80459-641-01E
Section 4—Installing the MCC 10/2012
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ENGLISH
Seismic Certification of Model 6
MCCs
Model 6 Motor Control Centers that are seismically certified have been
qualified to the site-specific seismic requirements of the listed model
building codes and/or standards. Optional construction features may be
required, depending on the location of the installation and the particular
code and/or standard of interest. Seismic certificates of compliance and
equipment labels are provided with all seismically certified MCCs. To
maintain the validity of this certification, the installation instructions provided
in this section must be followed.
Responsibility for Mitigation of Seismic
Damage
For the purposes of the model building codes, Model 6 Motor Control
Centers are considered nonstructural building components. Equipment
capacity was determined from tri-axial seismic shake table test results as
defined in the International Code Counsel Evaluation Service (ICC ES)
Acceptance Criteria for Seismic Qualification Testing of Nonstructural
Components (AC156).
Unless otherwise indicated, an equipment importance factor of 1.5 (I
P
= 1.5)
was used, indicating that equipment functionality was verified before and
after shaker table seismic simulation testing. This importance factor is
indicative of critical facilities where maximizing the probability of post event
functionality is a priority.
AC156 is published by the ICC ES and has been recognized by the Building
Seismic Safety Council (BSSC) as an appropriate methodology in the 2003
National Earthquake Hazard Reduction Program (NEHRP) commentary.
The National Institute of Building Sciences established the BSSC in1979 to
develop and promote regulatory provisions for earthquake risk mitigation at
the national level.
Incoming and outgoing cable and conduit must also be considered as
related but independent systems. They must be designed and restrained to
withstand the forces generated by the seismic event without increasing the
load transferred to the equipment. For applications where seismic hazard
exists, bottom entry and/or exit of cable and conduit is preferred.
If the spectral acceleration value (S
s
as defined by the International Building
Code or NFPA 5000) is in excess of 2.67g (such as the New Madrid seismic
area), then the equipment must also be braced at the top using a lateral
restraint system. A lateral restraint system is also required in situations
where horizontal motion at the top of the MCC is not be desirable (such as
applications where top entry and/or exit of conduit are used). This system
must be capable of transferring the loads created to the load-bearing path of
the building structural system.
Seismic qualification of nonstructural components by Schneider Electric is
just one link in the total chain of responsibility required to maximize the
probability that the equipment will be intact and functional after a seismic
event. During a seismic event, the equipment must be able to transfer the
loads that are created through the mounting pad and anchorage to the
load-bearing path of the building structural system.
The structural civil engineer or design engineer of record is responsible for
detailing the equipment connection and anchorage requirements (including
the lateral restraint system if appropriate) for the given installation. The
installer and manufacturers of the anchorage and lateral restraint system
are responsible for assuring that the mounting requirements are met.
Schneider Electric is not responsible for the specification and performance
of these systems.
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