731 SIGN LIGHTING AND ELECTRICAL SIGNS MATERIAL
731.01 Mercury Vapor Luminaire. Furnish mercury vapor luminaires that are complete lighting units consisting of a housing door frame, refractor lens, reflector, socket, and lamp. Ensure that the luminaire has a weatherproof optical system.
Ensure that the projected height of the luminaire including mounting device is not more than 11 inches (280 mm) high when positioned to provide optimum illumination of a sign face, 12 1/2 feet (3.8 m) high.
Furnish luminaire housing that:
A. Is cast aluminum having either a natural finish or a gray baked acrylic enamel.
B. Is adequately reinforced and capable of containing and supporting the reflector and lamp socket.
C. Has a flexible permanent-set and heat-resistant waterproof gasket between the housing and door frame. Suitably attach the gasket but so it is readily removable. Compress the gasket to form a weatherproof seal when the door frame is closed.
Furnish weepholes in the luminaire housing or cover as required for drainage.
Ensure that the door frame is either cast aluminum of the same finish as the housing or an aluminum extrusion with an anodized finish. Hinge the door frame on one edge, and fasten the door in place with spring loaded latches requiring no tools to open. Furnish stainless steel hinges, latches, and other external hardware. Ensure that the hinge retains the door frame in a secure condition when the door frame is opened and does not allow unintentional separation.
Furnish borosilicate glass, or its equivalent, refractor or lens of the optical system capable of withstanding thermal shock and the impact of freezing rain or hail. Furnish a waterproof seal between refractor or lens and the door frame consisting of a heat-resistant gasket or elastic cement.
Furnish an aluminum reflector to a shape that distributes light uniformly over the sign face, in conjunction with the lens or refractor supplied with the luminaire with the surface of the reflector finished to preserve the original reflective characteristics.
Ensure that the mercury lamp sockets are a mogul screw shell with a large center contact spring providing firm contact with the lamp base. Furnish a porcelain-shrouded socket that includes lamp grips.
The manufacturer will provide, in addition to catalog cuts submitted for determination of compliance, complete photometric data for each type luminaire as used with a 175-watt, H39KB-175 lamp. Ensure that the photometric performance data is certified by the manufacturer or a qualified independent testing laboratory. The minimum data required includes a tabulation of illumination values at the centers of 1-foot (0.3 m) square areas over a vertically-oriented 10 ´ 10-foot (3.0 ´ 3.0 m) square grid with the luminaire positioned 4 feet (1.2 m) in front of the vertical centerline of the grid and 1 foot (0.3 m) below the bottom edge of the grid. The data will include:
A. Maximum value obtained.
B. Minimum value obtained.
C. Average of the 100 measured values.
D. Ratio of the maximum to minimum values obtained no greater than 6.0.
E. Maximum ratio of illumination values obtained in any two contiguous areas.
Measure illumination using a cosine-corrected receptor in the plane of the grid with the receptor optical axis perpendicular to the plane of the grid. Ensure that the spectral response of the measuring device conforms to the CIE (Commission International del’Eclairage) standard “photopic” response. Ensure that the luminaire meets the following illumination requirements when tested under the above conditions:
1. Maximum illumination on any 1-foot (0.3 m) square area of 50 foot-candles (540 lx).
2. Average of the individual measurements of at least 20 foot-candles (215 lx).
3. Ratio of the maximum and minimum values obtained no greater than 6.0.
4. Maximum ratio of values obtained in any two contiguous areas no greater than 2.0.
The Engineer may require the following special test to confirm that a mercury-vapor luminaire meets the weatherproof requirements. Mount a luminaire complete with mounting connections and electrical conduit connections in a manner simulating actual service. Apply a water spray, adjusted to be equivalent to a driving rain, to the top, sides, and bottom for a period of one hour. Any entrance of water resulting in wetting of a normally live electrical component, or internal part of the optical assembly, is cause for rejection.
Furnish materials according to the Department’s Qualified Products List (QPL).
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 mounted 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.
C. Display Type. Furnish electrical changeable message signs consisting of a 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.
731.04 Changeable Message Sign, Drum Type. Mechanical drum changeable message signs consist of one or more drums of the required number of faces that are mechanically rotated.
Place signs in weatherproof cabinets. Integrate control logic units, load switches, monitor feedback circuits, power supply, etc., within the sign cabinet or mounted within a separate weatherproof enclosure as required.
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 sign lighting fixture is weatherproof and is shielded to project its output downward on the sign. 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 incandescent lamps.
Furnish materials according to the Department’s Qualified Products List (QPL).
731.07 School Speed Limit Sign Assembly. Furnish yellow beacons that are 6 inches (150 mm) or greater in size. 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.
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).