-3.32 PORTABLE CHANGEABLE MESSAGE SIGNS

12-3.32A(4) Quality Assurance

12-3.32B Materials

The text displayed on a sign must not scroll or travel horizontally or vertically across the face of the message panel.

The sign panel must be capable of displaying a 3-line message with at least 7 characters per line. The characters must be at least 18 inches in height where the useable shoulder area is at least 15 feet wide. To prevent encroachment onto the traveled way where the useable shoulder area is less than 15 feet wide, you may use a smaller message panel with at least 12-inch-high characters.

The message displayed on the sign must be visible from a distance of 1,500 feet and legible from a distance of 750 feet at noon on a cloudless day by persons with 20/20 vision or vision corrected to 20/20.

The sign face must be nonreflective black and protected from the glare of the sun by a method that does not interfere with the clarity of the sign message. The sign must be raised and lowered by means of a power-driven lifting mechanism.

Matrix signs must provide a complete alphanumeric selection.

Matrix-type signs using lamps must be equipped with an automatic-dimming mode that automatically compensates for the influence of temporary light sources or abnormal lighting conditions. The sign must have 3 or more manual dimming modes of different lamp intensities.

During the hours of darkness, matrix signs not using lamps must be either internally or externally illuminated.

The controller must be an all solid-state unit containing the necessary circuitry for the storage of at least 5 preprogrammed messages. The controller must be installed at a location that allows the operator to perform all functions from a single position. The controller must have a keyboard entry system that allows the operator to generate an infinite number of additional messages in addition to the preprogrammed stored messages. The keyboard must be equipped with a security lockout feature to prevent unauthorized use of the controller.

The controller must have:

1. Nonvolatile memory that stores keyboard-created messages during periods when the power is not activated

2. Variable display rate that allows the operator to match the information display to the speed of approaching traffic

12-3.32C Construction

Make a taper consisting of 9 traffic cones placed 25 feet apart to delineate the location of a PCMS except where the sign is placed behind guardrail or Type K temporary railing.

When in full operation, the bottom of a sign must be at least 7 feet above the ground and the top of the sign must be not more than 14.5 feet above the ground.

Operate the PCMS under the manufacturer's instructions.

Display only messages shown or ordered.

Repeat the entire message continuously in not more than 2 phases of at least 3 seconds per phase.

Approaching drivers must be able to read the entire message at least 2 times before passing the sign at the posted speed limit. Use more than 1 sign to comply with this requirement if necessary.

You must be available by cell phone during activities that require a sign. Be prepared to change the displayed message immediately upon request. You may operate the sign with a 24-hour timer control or remote control if authorized.

After the initial placement, move a sign from location to location as directed by the Engineer.

When not in use, move unprotected signs to an area at least 15 feet from the edge of the traveled way or remove them from the job site away from traffic.

12-3.32D Payment

12-3.33 TEMPORARY SIGNAL SYSTEMS

12-3.33A General

Temporary signal systems must comply with section 87.

The system must operate on a continuous, 24-hour basis unless traffic is controlled by flaggers.

12-3.33B Materials

12-3.33B(1) General

12-3.33B(2) Generators

In the event of a failure to supply voltage for the system, the backup generator must start automatically and transfer the system load upon reaching the operating voltage.

The system must have enough fuel storage to operate when it is unattended.

If a generator to back up commercial power is specified in the special provisions, the generator must have an automatic transfer switch.

Each generator must:

1. Be 120 V(ac) or 120/240 V(ac), 60 Hz, 2.5 kW minimum, continuous-duty type

2. Be powered by a gasoline, LPG, or diesel engine operating at approximately 1,800 rpm with an automatic oil feed

3. Be equipped to provide automatic start-stop operation with a 12 V starting system

4. Have generator output circuits that have overcurrent protection with a maximum setting of 15 A

12-3.33B(3) Automatic Transfer Switches

1. Line voltage monitoring in the event of a power outage that signals the generator to start.

2. Engine start delay, adjustable from 0 to 6 seconds, to prevent starting if the power outage is only momentary and an engine stop delay, adjustable from 0 to 8 minutes, to allow the generator set to run unloaded to cool before shut down.

3. Transfer delay from 0 to 120 seconds to allow the generator to stabilize before connecting to the load and retransfer delay from 0 to 32 minutes to allow the line voltage to stabilize.

4. Load-No Load switch to allow a test with or without load.

5. Normal-Test switch that will start and run the generator in the Test position. Normal position must return the generator to automatic operation.

6. Battery charger powered by the normal line voltage.

7. Generator voltage sensor that signals for a transfer if the generator output is ready.

1. Rated at 100 A for 120/240 V(ac)

2. 3 wire

3. Single phase

4. Compatible with the generator furnished
The switch must have a mechanical interlock to prevent an application of power to the load from both sources and to prevent backfeeding from the generator to the line.

12-3.33C Construction

12-3.33C(1) General

1. Commercial power from an existing utility company

2. Generator system
Do not use electrical power from existing highway facilities unless authorized.

Do not use power from private parties to provide power to the temporary signal system.

If the temporary signal system is out of operation, provide flaggers to maintain traffic control until the traffic signals are returned to service.

12-3.33C(2) Commercial Power

12-3.33D Payment