Rockwell Automation 2100 CENTERLINE MCC Installing a Vertical Grounding Strap - Manual (Page 2)

Publication 2100-IN066A-EN-P—August 2006
2 CENTERLINE® 2100 Motor Control Centers Installing a Vertical Grounding Strap in Series "E" to "J" Sections
3. If a horizontal ground bus is present:
a. Determine the horizontal ground bus location: top, bottom or both.
Remove the corresponding horizontal wireway cover(s).
NOTE: For motor control centers with horizontal ground bus in the top and
the bottom, decide which location is most convenient for connection to the
vertical grounding strap.
b. On the left side of the top or bottom horizontal wireway baffle
(whichever corresponds to the horizontal ground bus), locate the
circular knock-out. Use a hammer or a prybar (working from above
the top baffle, or from below the bottom baffle) to remove the
knock-out. Use pliers to twist off the knock-out if it remains attached
to the horizontal wireway baffle.
If no horizontal ground bus is present:
a. Decide whether the top or bottom of the section is most convenient
for cabling the end of the vertical grounding strap to the structure,
then remove that wireway cover and wireway baffle knock-out.
Installation Procedure Refer to figures 1 and 2, pages 3 and 4, for part illustrations.
1. One end of the vertical grounding strap has a slotted hole (oblong hole).
Insert that end through the hole created in the wireway baffle where the
knock-out was removed.
2. Position the vertical grounding strap to the left side of the six tabs
located on the left side of the red molded vertical bus cover. Align the
holes in the vertical grounding strap with the holes in the tabs.
3. Use six 1/4-20 x 1/2” thread-forming screws to bolt the vertical
grounding strap to the tabs. Insert screws from the right side of the tabs.
Torque the screws to 50 lb-in (5.7 N-m).
4. If a horizontal ground bus is present: Connect the vertical grounding strap to
the horizontal ground bus, using the L-shaped splice link (Figure 1, page
3). Use two 1/4-20 x 1/2” thread-forming screws to bolt the splice link
in place. Torque the screws to 50 lb-in (5.6 N-m).
If no horizontal ground bus is present: Attach one end of the grounding cable
to the vertical grounding strap, using the 1/4-20 x 1.0” screw, 1/4 flat
washer, 1/4 lock washer, and 1/4-20 nut (assemble as shown in
Figure 2, page 4). Insert a 1/4-20 x 1/2” thread-forming screw through
the other end of the grounding cable and into either of the bottom holes
in the front flange of the support (“C”) channel. Torque to 65 lb-in (7.3
N-m).