Emi shielding, Grounding, Wiring – Rockwell Automation 1391 USER MNL/DIGITAL AC SERVO DR User Manual

Page 65

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Chapter 7
Installation

7-4

Open ended shields (resolver feedback cable at the resolver and velocity
command cable at the servo drive) must be insulated so that they do not
accidentally cause ground loops.

EMI Shielding

The 1391-DES has an inverter carrier frequency of 2500 Hz. Therefore, the
system may induce noise into sensitive equipment lines adjacent to it.

ATTENTION: This drive can produce electromagnetic
radiation that may cause industrial or radio controlled
equipment to operate erratically and cause possible injury to
personnel.

The 1391-DES system is designed to be interconnected with
Allen-Bradley EMI shielded motor cables only. Do Not
substitute cables. The EMI shield of the motor cable only, must
be grounded at both ends to function properly.

!

Important: The thermal switch and brake wires are routed near motor
power and can pickup PWM radiation. Isolation from control devices may
be required.

Grounding

All equipment and components of a machine or process system shall have
their chassis connected to a common earth ground point. This ground
system provides a low impedance path that helps minimize shock hazards
to personnel and damage to equipment caused by short circuits, transient
overvoltages and accidental connection of energized conductors to the
equipment chassis.

Grounding requirements, conventions and definitions are contained in the
National Electrical Code. Local codes will usually dictate what particular
rules and regulations are to be followed concerning system safety grounds.
See Appendix B.

Wiring

ATTENTION: The National Electrical Code (NEC) and local
codes outline provisions for safely installing electrical
equipment. Installation must comply with specifications
regarding wire types, conductor sizes, branch circuit protection,
and disconnect devices. Failure to do so may result in personal
injury and/or equipment damage.

!

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