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

Table 2. Minimum separation distances from possible sources of EMI exceeding 5 kVa
Condition
Unshielded power lines of electrical equipment in proximity to open
or nonmetal pathways.
Unshielded power lines or electrical equipment in proximity to a
grounded metal conduit pathway
Power lines enclosed in a grounded metal conduit (or equivalent
shielding) in proximity to a grounded metal conduit pathway
Electrical motors and transformers
Minimum Separation
Distance
610 mm
(24 inches)
300 mm
(12 inches)
150 mm
(6 inches)
1200 mm
(47 inches)
6) Verify material and tool availability.
Before beginning the installation of a cable support system, be sure that the required materials,
hand tools, and power tools are available. This should also include safety tools such as safety
glasses and, where required, hardhats.
7) Mount distribution-rings.
Review the designer’s drawing and specifications to determine exact placement, quantity, size,
and type of distribution-rings.
Install the distribution-rings, working from the top left side of the plywood backboard to the
bottom right side of the plywood backboard.
Measure the location of the first distribution ring to be installed according to the designer’s
documents.
Position the distribution-ring on the backboard and install the screws to secure the distribution
ring.
8) Installing J-hooks.
Determine the J-hook size required in each cable path and lay them out along the cable route,
an average of 5 ft apart.
Identify the location of the first J hook to be installed.
Position the J-hook at its designated location and mark the holes for the anchors.
Pre-drill the holes and install the anchors. Depending on the type of structure, (i.e., a masonry
structure will require one type of anchor while metal structures or drywall will require others).
Install the anchors.
Reposition the J-hook at the anchor(s).
Install the screw(s) through the hole(s) in the J-hook and into the anchor, securing the J-hook to
the anchor(s).
Install the remaining J-hooks using the same procedures.
9) Install cable tray systems.
The process of installing a cable tray or trays is manufacturer specific, due to the many
different sizes, types, and configurations. Consult the manufacturer’s specifications and
installation guidelines prior to installing these pathways.
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