with reference to the pavement.
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Sides and bottom of each light base shall be sandblasted immediately prior
to installation. Inside faces of bored hole and bottom and sides of light
base shall be covered with a coating of sealant. Sealant shall completely
fill the void between concrete and base. A jig or holding device shall be
used for installing each light fixture to ensure positioning to the proper
elevation, alignment, level control, and azimuth control. Light fixture
shall be oriented with light beams parallel to the preferred direction of
approach to the helipad. Level outermost edge of fixture with the
surrounding pavement. Surplus sealant or flexible embedding material shall
be removed. The holding device shall be left in place until sealant has
reached its initial set. Fixture lead wires shall be properly arranged
with respect to their connecting position. The wire way entrance into the
light recess shall be blocked to retain the sealant material during curing.
3.12.7
Installation of Circuit Wires in Pavement
Wires shall be placed in saw kerfs and anchored at bottom by means of
rubber or plastic wedges or noncorrosive metal clips placed every 600 or
900 mm 2 or 3 feet or as often as necessary to hold the wire down. Wires
crossing existing joints shall be encased in a 300 mm 12 inch length of
flexible tubing of polyethylene material conforming to ASTM D 1248, Type II
or Type III, to break the bond between the wires and the sealing material.
Flexible tubing shall be centered on the joint and of sufficient size to
accommodate the wires to allow for movement of the wires as the joint opens
and closes. Ends of tubing shall be wrapped with tape to prevent entrance
of sealing materials. The adjacent joint area shall be packed temporarily
with roving material, such as hemp, jute, cotton, or flax, to prevent
sealing material from flowing into the open joint. Sealing materials shall
be mixed and applied in accordance with the manufacturer's instructions and
at the recommended temperature. Surplus or spilled material shall be
removed.
3.13
SPLICES FOR HELIPAD LIGHTING CABLE
3.13.1
Connectors
Kit type connectors shall be used to splice 5 kV single-conductor series
lighting cables. During installation and prior to covering with earth,
mating surfaces of connectors shall be covered until connected and cleaned
when plugged together. At joint where connectors come together, install
heat shrinkable tubing with waterproof sealant. Alternately, the
Contractor may provide two half lapped layers of tape over the entire
joint. Joint shall prevent entrapment of air which might subsequently
loosen the joint.
3.13.2
Splicing Fixtures to the Wires in Pavement Saw Kerfs
Splices shall be made with pre-insulated watertight connector sleeves
crimped with a tool that requires a complete crimp before tool can be
removed.
3.14
GROUNDING SYSTEMS
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NOTE: The preferred method of grounding is to have
grounding circuit separate and not connected to the
SECTION 16525A
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