Rev.11-1-95

CHANGEABLE MESSAGE SIGNS

801-T-063

The Standard Specifications are revised as follows:

 

SECTION 801, AFTER LINE 54, INSERT AS FOLLOWS:

The changeable message sign equipment supplied shall be a standard model produced by a manufacturer with experience in the production of trailer-mounted, generator powered electronic equipment. All workmanship, materials, and assembly procedures shall be of quality design. Each component of the complete unit shall be adequate for and compatible with all structural and performance demands placed upon it as a part of the complete unit. The equipment shall remain operational under inclement weather conditions. An operation manual, parts manual, trouble shooting guide, and wiring diagrams shall be supplied with the unit.

SECTION 801, AFTER LINE 118, INSERT AS FOLLOWS:

801.03.1 Changeable Message Sign. This work shall consist of furnishing, installing, and maintaining a trailer-mounted, portable sign upon which varying electronically generated messages will be displayed to highway traffic as advisories or for the purposes of warning or control.

A field service kit of parts shall be available as an option. As a minimum, the kit shall include one of each type of circuit board including control and driver, one character block, 10 flip dots, and all proprietary or speciality parts which are user changeable but not readily available from local sources. The field service kit contents list and a price list of all parts and their availability shall be provided with each sign. Such lists shall be made available to the Department for review prior to approval.

The sign shall be capable of presenting 3 lines of message copy. As a minimum, each line shall display words of up to 8 characters in length in various moving patterns to produce messages. The sign shall also present moving arrow patterns when desired in lieu of language oriented messages. The sign shall have capability to display multiple messages in sequence and with variable timing under computer control. The sign shall be capable of changing to and displaying a programmed default message in the event of power failure. The sign shall be clearly visible and legible from a distance of 230 m (750 ft) under both day and night conditions.

The unit shall require a maximum of 2 kW of power for full operation. The unit shall be capable of utilizing power from a self-contained generator or alternator, or from a 120 V utility hookup. The unit shall be capable of continuous operation for a minimum of 5 days and shall carry sufficient fuel to meet this requirement without service attention. The unit shall be equipped with a self-contained battery system.

An indicator which is visible to service personnel driving past the sign, shall be provided to show when the primary power source has failed and the sign is operating from backup batteries. Battery backup shall fully operate the sign with lights for a minimum of 8 h after primary power failure. The sign shall revert to a user defined default message at the end of the usable backup battery life. Solar power may be used to supplement the generating system.

The trailer and all mounted equipment shall be structurally adequate for unlimited, normal operation in wind velocities of up to 100 km/h (60 mph). The complete structure, including all components of the message sign, shall not require precise leveling for sustained operation. The equipment shall be designed to enable one person to perform all transporting and operating functions easily and effectively without assistance.

(a) Trailer. The 2-wheel trailer shall be structurally adequate to serve both as a carrier and as an operating platform for all components of the complete unit. The minimum basic structure shall be structural steel tubing equivalent to 50 mm x 100 mm x 4.8 mm (2 in. x 4 in. x 3/16 in.). All tubing shall be joined by welding, and all structural welds shall be continuous bead welds in accordance with 711.32.

Axle and suspension systems shall be rated at 1,590 kg (3,500 lb) minimum. Wheels and tires shall be a minimum of 380 mm (15 in.), 4 ply, and shall be rated for towing at on-highway speeds of 105 km/h (65 mph). A steel flat topped style fender shall be installed over each wheel. A license plate mounting location which is visible from the rear of the trailer shall be provided such that the mounted plate shall not protrude from the trailer. Maximum overall towing width shall be 2.4 m (8'-0").

Four outriggers with leveling jacks, one at each corner of the trailer deck, shall be installed. Non-slip foot treads shall be provided at locations on the trailer where climbing and standing is expected for setup, takedown, service, and maintenance.

The trailer lighting system shall include tail lights, stop lights, turn signals, marker lights, and a license plate light along with reflex reflectors. A trailer electrical cable and connector compatible with towing vehicles shall be installed. The trailer hitch shall be a ring to fit a T-90-A pintle hook. Vertical adjustment of the ring from 450 mm to 610 mm (18 in. to 24 in.) shall be provided.

A double safety chain will be required.

The trailer shall be in accordance with State law for operation on the highway.

(b) Message Sign. The message sign shall be a weld-up of channel formed aluminum and aluminum plate, or bend formed and welded aluminum plate. All welds shall be continuous. The length shall be approximately 2.8 m to 3.2 m (110 in. to 126 in.). The height shall be approximately 2.8 m to 2.0 m to 2.2 m (78 in. to 87 in.). The depth shall be approximately 250 mm to 330 mm (10 in. to 13 in.). The front face of the sign shall be covered with clear poly-carbonate material.

Message characters shall be delineated by electromagnetically actuated dots operating on a dot matrix principle under the control of a digital computer. Matrix configuration shall display characters in a nominal 5-dot horizontal by 7-dot vertical arrangement. The display size of the dot shall be approximately 64 mm (2.5 inches) high by 41 mm (1.625 in.) wide, or if circular, a minimum of 54 mm (2.125 in.) in diameter. Character height shall be approximately 460 mm (18 in.). Minimum character widths shall approximate those given for 460 mm (18 in.) Series B letters in the Standard Alphabets for Highway Signs. Minimum spacing between characters shall be equal to one dot width. Minimum spacing between lines shall be approximately one-third of the character height. Dot color shall be fluorescent yellow when activated by computer signal or flat black when not activated. Magnetic action shall swing the active element of each dot around a hinge to display the appropriate color.

Speed of actuation shall enable complete change of all 3 lines of message copy in not more than 400 milliseconds. Message display timing shall be controllable in steps not larger than one second from a minimum of 1.0 sec to 6.0 sec. A controllable blankout period from 0 sec to 2 sec shall be available between messages. The sign shall be capable of holding a single message indefinitely.

A message lighting system consisting of ultraviolet, fluorescent light bulbs under automatic control above and below each message line shall illuminate the sign during darkness or low light level conditions.

The message sign shall be supported on a telescoping upright member in a manner permitting raising the sign for operation and lowering the sign for transport. The upright shall include a device to enable a minimum 36E degree rotation of the sign. The sign shall lock, by means of a brake, into the position to which it is manually rotated. Raise and lower travel shall nominally be a minimum of 1.2 m (4 ft). Such travel shall be powered by an electric hydraulic pump operating a hydraulic cylinder. A locking device to prevent accidental lowering shall be provided. A manual lowering control for the sign shall be provided with a rate not to exceed 150 mm (0.5 ft) per sec if the electric pump fails. The bottom of the sign shall be at least 2.1 m (7 ft) above the ground when in the raised position. In a transport position, the sign shall orient to the longitudinal axis of the trailer in a manner that effectively reduces aerodynamic drag during towing.

All electrical, electronic, and mechanical components shall be readily accessible for service or repair.

(c) Computer and Control. The message sign shall be controlled in all function by an on-board digital computer which shall include the features as follows:

1. Be of solid state design and be removable

2. Include a standard typewriter configuration keyboard through which user originated messages may be entered for display or storage

3. Be capable of message programming from an IBM compatible computer which shall be removable while the sign continues to normally operate. While removed, the laptop computer shall be capable of operating to permit programming of messages for subsequent loading into the message sign by plugging the laptop computer into the sign using a standard interface such as RS-232.

4. Have a laptop computer available as an option

5. Have IBM compatible programming software and documentation available as an option

6. Include a liquid crystal display screen upon which actual messages, and not message code numbers, may be reviewed and sequenced before display on the message sign

7. Store a minimum of 100 preprogrammed messages for display when called up by an operator through the keyboard

8. Store a minimum of 50 user originated messages

9. Maintain and display a stored message list

10. Provide access coding or key entry for changing user oriented messages.

11. Provide control programming to present sequenced messages under operator control through keyboard entry

12. Provide control for moving arrow displays

13. Be capable of connection with, communication through, and complete control via a dial-up telephone line or cellular telephone as an option at the time of purchase or as a retrofit after purchase

14. Be capable of time-of-day operation to change or display messages with programming for a minimum of one year

 

The computer shall be equipped with a backup battery to maintain memories when onboard or utility power is not available. The computer shall be housed in a weather resistant, shock resistant, vibration resistant casing which shall include a light for night operation. All primary start/stop and other switching functions shall be contained in the control housing. Secondary switches may be provided at other secured locations on the sign to facilitate maintenance.

(d) Power and Miscellaneous Equipment. All electric power for full operation of this unit shall be generated by a diesel engine driving a generator or alternator, the output of which shall not exceed 120 volts. The engine, alternator, or generator shall include the features as follows:

1. Electric starting capability

2. Engine manufacturer's recommended fuel and oil filters

3. A fuel tank sized for a minimum of 5 days of continuous operation

4. Circuit breaker protection and voltage regulation for the generator or alternator

5. An audible warning prior to automatic engine startup

6. Gages including fuel level, engine hours, and battery voltages

 

The input for the 120 V utility hookup shall be through a standard twist-lock 3-prong male connector, similar to a NEMA L5-20 configuration, on the sign mated with a female plug to be supplied with the sign. Switching shall be provided such that onboard generated 120 V potential is not present on the utility hookup male connector prongs.

Surge, spike, and transient protection of the electronics shall be provided for both onboard generated and external power.

Each compartment of the complete unit shall be enclosed in a manner intended for preclude theft or vandalism. Protection shall be provided for the compartments as follows:

1. The computer and control compartment

2. The engine and generator compartment

3. The battery compartment

4. The fuel tank

5. The external 120 V utility hookup connection

The complete unit shall be painted with 2 coats of orange paint in accordance with the MUTCD.

(e) Documentation. A complete operating and maintenance manual, parts book with standard electronic part numbers and manufacturer's part numbers, service manual, wiring diagrams, and schematic diagrams shall be provided with each sign unit.

(f) Warranty. The manufacturer shall warrant the complete unit for one full year from the date of delivery. The warranty shall cover all parts, computer, messages sign, diesel engine, trailer, wiring, and all labor required for repair of the unit if failure occurs. The manufacturer shall send a representative to demonstrate the equipment to the Engineer and Contractor with no additional payment. A one year extended warranty shall be available as an option, at a reasonable price, for the complete unit.

A malfunctioning sign shall be repaired or replaced within 24 hours.

(g) Delivery Date. The manufacturer shall be able to deliver the units within 45 calendar days after the date of award of the contract.

SECTION 801, LINE 627, INSERT AS FOLLOWS:

be measured by the number of units installed, maintained, and removed. Changeable message signs will be measured by the number of units furnished, installed as shown on the plans or as directed, and maintained in accordance with the manufacturer's recommendations. A maintenance log shall be kept for each sign.

 

SECTION 801, BEGIN LINE 651, INSERT AS FOLLOWS:

801.18 Basis of Payment. The accepted quantities of construction signs, detour route marker assemblies, changeable message signs, temporaty worksite speed limit sign assemblies, road closure sign assemblies, and temporary raised pavement markers will be paid for at the contract unit price per each. Payment for temporary worksite speed limit assemblies will be made

SECTION 801, AFTER LINE 690, INSERT AS FOLLOWS:

Changeable Message Sign. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EACH

SECTION 801, AFTER LINE 735, INSERT AS FOLLOWS:

The costs of required options shall be included in the cost of changeable message sign. However, each unit will be paid for only once regardless of how many times it is moved or replaced, or how many times the sign message is altered. For each day or fraction thereof on which the sign is not operational when deemed required, a proportionate deduction of the contract price will be made for material not furnished. When no longer required for the contract, each unit with all optional equipment and remaining warranty shall become the property of the Contractor.