Allen-Bradley 1512B, User Manual

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86 Rockwell Automation Publication 1500-UM055I-EN-P - December 2021
Appendix B ArcShield Plenum Installation Instructions
Cabinet Preparation
In preparation to mount the plenum:
1. Remove the cabinet lifting means (slips of lifting angles).
2. Reinstall the 5/8-11 bolts retaining the lifting means in the holes from
where they came (11 lb•ft [14.5 N•m]). Failure to install the bolts negates
the cabinets ability to control any arc gases properly.
3. After the lifting angles or clips are removed, remove 1/4-20 fasteners
from the relief vent on the top of the MV enclosure. Leave the (4) corner
fasteners in place.
The plenums are designed to fit over the fastener heads at the (4) corners of the
relief vent. The corner fasteners are required to secure the relief vent during
installation.
Plenum Placement on Structure
Once the plenum has been lifted in place directly over the relief vent (shown in
Figure 80 ), all 1/4-20 fasteners (15 N•m [12 lb•ft]), removed in Cabinet
Preparation above, are replaced to attach the plenum to the top of the
enclosure. Use hand tools only.
ATTENTION: Hardware used to retain the lifting provision hardware
must be reinstalled in the same holes. Failure to replace this hardware
will make the arc resistance of the cabinet ineffective and could
subject personnel to the possibility of severe burns, injury, or death.
IMPORTANT
Do not remove the four corner fasteners ( Figure 79 )
Figure 78 - Relief Vent Fasteners (top view) Figure 79 - Relief Vent
Relief vent
Relief fasteners
Corner fasteners