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 Departmentís 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 Departmentís 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 Departmentís 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 Departmentís Qualified Products List (QPL) for LED signal lamps.

Furnish materials according to the Departmentís 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 Departmentís Qualified Products List (QPL) for LED signal lamps.

 Furnish materials according to the Departmentís 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 Departmentís 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 Departmentís Qualified Products List (QPL).