Rockwell Automation 2100 CENTERLINE Low Voltage Motor Control Centers User Manual
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Rockwell Automation Publication 2100-IN012E-EN-P - February 2012
Chapter 7 Final Checklist Before Energizing
Conduct this test using an insulation resistance tester (megger) with a
potential of 500…1000V. This megger test should be conducted phase-to-
phase, phase-to-ground, and when applicable, phase-to-neutral on the
MCC buswork. The test should be conducted with all of the switches or
circuit breakers in the open or OFF/O positions. Typical insulation
resistance values are 50 M
Ω or greater.
Next, check the field wiring; for example, motor cables and incoming line
cables. Insulation resistance values are affected by temperature, humidity,
or dampness, which may cause a considerably lower insulation resistance
reading. If the insulation resistance values are below 1 M
Ω (for example,
affected by dampness, temperature, or humidity) or the MCC has been
stored in a damp or humid area, we recommend that the equipment be
dried out. Dry out the motor cables by injecting a low voltage current or by
using space heaters.
Once the equipment is dry, repeat the insulation resistance test. The
minimum value for insulation resistance on a new installation at startup or
energizing is 1 M
Ω. These readings may be recorded in the
Megger
Reading Recording Table
. This table allows for additional megger readings
to be recorded during regular maintenance periods.
20.
Check that all arc-resistant parts are installed.
See
ArcShield Components
for more information.
21.
Check that all unit latches are secure.
See
for more information.
22.
Check that all section closing plates are in place.
23.
Check that any SecureConnect units are properly installed.
See
for more information.
24.
Close and latch all doors, making certain that no wires are pinched.
Certain applications may have latch requirements different from those
provided. If you have questions regarding proper latching, contact
Rockwell Automation LV MCC Technical Support at 1.440.646.5800 and
follow the prompts to Allen-Bradley>Low Voltage Motor Control
Centers>Post Shipment Support.
Refer to the following illustrations for various latch placements.