User Manual Owner's manual

Rockwell Automation Publication 280E-UM001B-EN-P - July 2012 45
Installation and Wiring Chapter 2
Group Motor Installations for USA and Canada Markets
The ArmorStart Distributed Motor controllers are listed for use with each other
in group installations per NFPA 79, Electrical Standard for Industrial Machinery.
When applied according to the group motor installation requirements, two or
more motors, of any rating or controller type, are permitted on a single branch
circuit. Group Motor Installation has been successfully used for many years in the
USA and Canada.
Note: For additional information regarding group motor installations with the
ArmorStart Distributed Motor Controller, see Appendix A
.
Wiring and Workmanship Guidelines
In addition to conduit and seal-tite raceway, it is acceptable to utilize cable that is
dual rated Tray Cable Exposed Runs (TC-ER) and Cord, STOOW, for power
and control wiring on ArmorStart installations. In the USA and Canada
installations, the following guidance is outlined by the National Electrical Code
(NEC) and National Fire Protection Association (NFPA) 79.
In industrial establishments where the conditions of maintenance and
supervision ensure that only qualified persons service the installation, and where
the exposed cable is continuously supported and protected against physical
damage using mechanical protection, such as struts, angles, or channels, Type TC
tray cable that complies with the crush and impact requirements of Type MC
(Metal Clad) cable and is identified for such use with the marking Type TC-ER
(Exposed Run)* shall be permitted between a cable tray and the utilization
equipment or device as open wiring. The cable shall be secured at intervals not
exceeding 1.8 m (6 ft) and installed in a “good workman-like” manner.
Equipment grounding for the utilization equipment shall be provided by an
equipment grounding conductor within the cable.
*Historically cable meeting these crush and impact requirements were designated
and marked “Open Wiring”. Cable so marked is equivalent to the present Type
TC-ER and can be used.
While the ArmorStart is intended for installation in factory floor environments
of industrial establishments, the following must be taken into consideration when
locating the ArmorStart in the application:
• Cables, including those for control voltage including 24V DC and
communications, are not to be exposed to an operator or building traffic
on a continuous basis.
• Location of the ArmorStart to minimize exposure to continual traffic is
recommended. If location to minimize traffic flow is unavoidable, other
barriers to minimize inadvertent exposure to the cabling should be
considered.