731 SIGN LIGHTING AND ELECTRICAL SIGNS MATERIAL
731.03 Changeable Message Sign, Electrical Type.
A. General. Electrical changeable message signs consist of
units or groups of units containing arrangements of pixels that use electrical circuitry
to display different messages.
Place signs in
weatherproof cabinets. Integrate control logic units, load switches,
monitor feedback circuits, power supply, etc., within the sign cabinet or mount
within a separate weatherproof enclosure as required.
B. Message Type. Furnish electrical changeable message signs of
the limited message or unlimited message type.
Limited message signs
contain pixels in an arrangement so that by the energizing of selected pixels
two or more messages may be displayed.
Unlimited message
signs contain pixels arranged in full matrix or alphanumeric type modules
positioned side-by-side to provide line units of the specified length.
Ensure that the line units are capable of displaying messages containing
letters and numerals, limited only by the number of characters that can be
accommodated. Ensure that the line units are capable of continually
displaying alternating messages.
Furnish materials
according to the Department’s Qualified
Products List (QPL).
C. Display Type. Furnish electrical changeable message signs
consisting of lamp, light emitting diode, fiber optic, light reflecting, or
hybrid types.
Lamp type changeable
message signs consist of individual incandescent bulbs.
Light emitting diode
changeable message signs consist of groups of individual light emitting diodes
that, acting together, form individual character pixels.
Fiber optic
changeable message signs consist of fiber optic bundles that transmit light
from a remote source to form individual pixels.
Light reflecting
changeable message signs consist of individual light reflecting panels.
Hybrid changeable
message signs consist of individual light reflecting panels, each augmented by
a light emitting pixel of the specified type. Ensure that the light
emitting pixels are displayed when the corresponding reflecting panel is in the
exposed position, and concealed or de-energized when the corresponding reflecting
panel is in the unexposed position.
Furnish materials
according to the Department’s Qualified
Products List (QPL).
731.05 Internally Illuminated Fixed Message Sign. Furnish
internally illuminated fixed message signs of the required legend and that
consist of an opaque housing with a face of translucent plastic. If
specified, provide double faced signs. Illuminate signs using interior
lamps located so the sign face is uniformly lighted.
Furnish
signs either with the legend on the exterior surface to maintain legibility
when unlighted due to power failure, or with the legend on the interior surface
so as to be invisible when the sign is unlighted. Apply the legend using
black silk screening or by direct applied characters to white sign faces,
unless otherwise specified. Design the sign faces for quick removal for
maintenance, and provide faces with a safety chain or like device. If
specified, shield the sign faces with sunscreens, louvering,
or visors.
Furnish
housings made of corrosion-resistant material that is cast, extruded, or
formed. Furnish mounting hubs that are similar to traffic signal
design. Furnish weatherproof signs that have drainage weepholes.
Furnish
the sign with the appropriate hardware for mounting by span wire, mast arm,
pedestal top, or pole type bracket arms. Include fluorescent type lamps
with ballast.
Furnish
materials according to the Department’s Qualified
Products List (QPL).
731.06 Sign Flasher Assembly. Furnish
beacons consisting of single traffic signal sections with 8 or 12-inch (200 or
300 mm) yellow lenses. Ensure that the flasher control unit flashes
the beacons at a rate for each beacon of between 50 to 60 times per minute with
the light period from one-half to two-thirds of the total cycle. Furnish
flasher control units that have all solid state components and that meet NEMA TS-1, part 6. House
control units within a weatherproof corrosion-resistant enclosure with a
lockable door. Include the LED lamps.
Ensure
that the manufacturer of LED beacons is listed on the Department’s Qualified
Products List (QPL) for LED signal lamps.
Furnish
materials according to the Department’s Qualified
Products List (QPL).
731.07 School Speed Limit Sign Assembly. Furnish
yellow beacons that are 8 inches (200 mm) or 12 inches (300 mm). Ensure
that the flashers flash the beacons alternately at a rate for each beacon of 50
to 60 times per minute with the light period from one-half to two-thirds of the
total cycle. Furnish flashers that have all solid state components and
that meet NEMA TS-1, part 6. Ensure that the backing
members with hardware are compatible with the method of support.
Ensure
that the manufacturer of LED beacons is listed on the Department’s Qualified
Products List (QPL) for LED signal lamps.
Furnish
materials according to the Department’s Qualified
Products List (QPL).
731.08 Flexible Conduit. Furnish
galvanized steel flextube conduit with a waterproof
PVC jacket according to UL 360 for wiring of lighted signs.
Furnish
materials according to the Department’s Qualified
Products List (QPL).
731.10 Timer with Enclosure. Furnish a
timer that allows automatic sign operation for a minimum of 8 times per day and
for selected days of the week. Furnish a solid state timer with a back-up
battery to maintain timekeeping and program memory for at least 48 hours.
Furnish a battery with a design life of 10 years under field conditions when
power failures over the 10-year period would accumulate to 100 days. If
installed outdoors, house the timer within a lockable, weatherproof,
corrosion-resistant enclosure. Furnish each enclosure with at least one
padlock complying with 631.06.
Furnish
materials according to the Department’s Qualified
Products List (QPL).