2010 Construction and Material Specifications - Ohio Department of ...

725.21
Ensure that the luminaire ring is equipped with three positive latching devices
equally spaced around the ring that latch to the head frame supporting the ring in
the raised position allowing tension to be removed from the lifting cables. Ensure
that all moving parts of each latching device are part of the ring portion of the latch
assembly and that each latch assembly incorporates a reflectorized flag that is
clearly discernible from the ground when the ring is latched to the head frame.
Ensure that the latching sequence shall not exert a horizontal force sufficient to
cause an excess of 4 g's acceleration upon the luminaires.
Ensure that the luminaire ring is equipped with a NEMA 4 corrosion resistant
junction box for the connections between the main power cord bringing power to
the ring and the separate power cords for each luminaire. Ensure that each power
cord has copper conductors of adequate size and insulation, that each power cord is
of suitable construction, and that each power cord enters the junction box through
a weather tight cord connector. Ensure that there is a cord support capable of
withstanding a load of 1-1/2 times the weight of the main power cord without
damage to the cord transmitting the weight of the main power cord directly to the
ring. Ensure that there is a weather tight power inlet on the luminaire ring which
allows the main power cord in the base of the tower to connect to the ring when
the ring is in the lowered position. Ensure that the junction box is equipped with a
600 volt class terminal block for the connections between the main power cord, the
luminaire power cords and the power inlet cord. Ensure that each luminaire ring is
identified by a raised or engraved marking applied in a prominent location which
identifies the manufacturer and the year that the ring was manufactured and that
such marking remains legible after the ring has been galvanized
2. Head Frame Assembly. Ensure that the head frame is fabricated from steel
which conforms to the requirements of ASTM A 36/A 36M. Ensure that the head
frame assembly is equipped with pulleys for the wire ropes hoisting cables and
rollers for the main power cord to the luminaire ring. Ensure that each hoisting
cable sheave has a tread diameter of at least 20 times the cable diameter for
galvanized cable and 25 times the cable diameter for stainless steel cable, that the
groove for the hoisting cable has a semi-circular in cross section with a radius of
one-half the cable diameter plus 1/64 inch(0.4 mm), that the sheave has an
oil-impregnated bronze bushing and that the shaft on which the sheave turns is of
stainless steel. Ensure that the rollers for power cord run on AISI 304 stainless
steel shafts between cold-rolled steel plates. Ensure that bending radius of the
power cord is not less than 7 inches (180 mm). Ensure that keeper bars have been
provided over the power cord and ring support cables to keep them in their
respective tracks. Ensure that a guide is provided to separate the individual cables
as they pass between the head frame and the top of the pole. Ensure that the head
frame mechanism is protected from the weather by a domed cover of either copper
free spun aluminum or fiberglass. Ensure that each head frame is identified by a
raised or engraved marking applied in a prominent location which identifies the
manufacturer and the year that the head frame was manufactured and that such
marking remains legible after the head frame has been galvanized.
3. Transition Plate. Ensure that there is a transition plate between the ring
support cables and the main hoisting cable. Ensure that the luminaire ring support
cables are secured to the transition plate by shop applied, swage-type fittings
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