Programming Documents for Pre-K for SA - The City of San Antonio

c. Two or more additional welds shall not exceed the one-inch spacing from the end
welds toward the center of the busbar.
d. The No. 3/0 AWG insulated ground wire weld ends shall have a minimum amount of
wire exposure from the conduit to the weld and a minimum amount of insulation
removed at weld.
8.4.8.4 Equipment Cabinets and Racks
1. The busbar shall be installed at the base and back of each cabinet and rack.
2. Each cabinet and rack shall be provided with a No. 6 AWG insulated ground wire home run
to the TGB, except as noted:
a. In a cabinet or rack bay, provide a home run ground wire to the first cabinet or rack
from the wall.
b. From the first cabinet or rack, the No. 6 AWG insulated ground wire may be looped
from cabinet frame to cabinet frame (or rack to rack, where applicable), connecting to
each cabinet frame (or rack) ground busbar, not to exceed four adjacent cabinets (or
racks).
c. Do not loop from rack to cabinet.
3. Each cabinet or rack bay against the wall shall be bottom/side ground feeds from the wall.
a. Wall ground feeds/raceways to racks shall not be exposed on the walls.
b. Exception: Some cabinet or rack bays will require the ground to be fed from the
ceiling raceway. Refer to drawings for details.
4. All ground raceways within each cabinet (or on each rack, where applicable) or cabinet base
and adjacent ganged cabinet base shall be an insulated metallic flex type raceway and shall not
interfere with equipment mounting framing or equipment mounting brackets.
5. Each ground feed shall provide proper installation allowances and penetration depths to
provide conversion fittings from solid metallic to insulated metallic flex conduit raceways.
6. To bond each cabinet and rack to ground, sand clean a one square inch area, drill, tap, and
bolt conductor and connector to sanded area.
8.4.8.5 Cable Tray/Runway, Cable Raceway and Support Systems Grounding:
1. Provide communications cable tray and cable runway systems with a communications
isolated ground from the nearest TGB.
2. Provide and install No. 6 AWG insulated ground wire to one end of each cable tray/runway
system and home run to nearest TGB.
3. Communications cable tray/runway that is located in the same room as the TMGB shall be
connected to the TMGB.
4. Provide grounding path between cable tray/runway sections with grounding strap, Cooper B-
Line part number SB-669-1 or submitted and owner-approved equivalent.
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