607— Truck-Mounted Traffic Control Devices

600-77 Section 607 — Truck -Mounted Traffic Control Devices

607.1 Description 1 Provide, install, and maintain truck -mounted traffic control devices. Truck -mounted advance warning arrow panels and truck -mounted changeable message signs are not included in any category as an individual traffic control device since these devices are supplemental to the vehicles. 607.2 Materials 607.2.1 Truck and Accessories 1 Mount truck mounted traffic control devices as a permanent fixture to the truck to provide a minimum height of 7 ft from the bottom of the panel face to the surface on which the truck is operating when the device is in its operating position. Attach the unit to the frame of the truck through use of a sufficient number of fasteners to prevent the structure from detaching from the frame of the truck during an impact from an errant vehicle. Do not place or attempt to mount a trailer -mounted unit on a truck. 607.2.2 Power System 1 Provide a 12- volt electrical system powered from a 12- volt DC power source or an adaptable 110- volt or 120- volt AC power source to operate truck -mounted devices. Equip each unit powered by a DC electrical power source with an automatic lamp intensity regulator to maintain constant power outputs during battery voltage variances and a voltage indicator or warning device to indicate when the batteries require recharging. Locate the lamp intensity regulator and the voltage indicator in a convenient location f or easy access and visibility for reading by the operator. 2 Obtain operating power for the truck -mounted device from the vehicle, a truck -mounted generating plant, solar assisted facilities , or an adaptable 110- volt or 120- volt AC power source. Use of a portable generator for a power source is unacceptable. Regardless of the source, provide a supply of electrical energy capable of operating the device as required by the Specifications, the Standard Drawings , the Plans , and the MUTCD . 607.2.3 Power Sources 607.2.3.1 Vehicle Based Power 1 Operating the truck -mounted device at an optimal voltage of 12- volt DC and obtaining the electrical power necessary for operation from the vehicle’s alternator and battery system of a truck -mounted generating plant is an acceptable power source with prior RCE approval. However, do not use the