Glossary
30
Glossary
Auxiliary Control Panel (ACP):
A user interface for the DDMS controller, which contains
an LCD and keypad. The ACP is located within the DDMS cabinet or a laptop interface
enclosure.
Central Controller:
Software system that can control displays remotely. This software
contains a message studio, schedule studio, a display manager, and other tools and
options that are used to configure displays and networks for an Intelligent Transportation
System.
Control Enclosure:
A cabinet with the same dimensions as the power and control
enclosure, but it contains only control equipment, such as the DDMS controller. It
pairs with a separate power enclosure. Control enclosures can be either wall or pole
mounted.
DC Terminal Assembly:
A component that distributes DC power and signal to the LED
panel(s).
DDMS Controller:
A component located in the DDMS cabinet that is responsible for
handling communications, interpreting sensors, performing diagnostics, and playing
messages on the LED panel modules.
Dedicated Dynamic Message Sign (DDMS):
A dynamic message sign that gives travelers
information about a specific lane on a roadway. Such displays may provide toll rates,
travel times, or open / close status.
Eyebolt:
Heavy steel bolt with a loop attached to the top of the LED panel cabinet for
lifting.
Fire-to-Wire Enclosure:
A cabinet that contains the VM CAN distribution board, which
converts fiber cable to copper wire as required by the LED panel(s).
Isolation Board:
A component that distributes DC power from the power supplies to the
LED panels.
Laptop Interface Enclosure (LIE):
An enclosure that provides a control location away from
the DDMS cabinet.
Light Emitting Diode (LED):
Low-energy, high-intensity lighting unit. A cluster of LEDs forms
a pixel on the LED panel.
Module:
A component containing an array of LED pixels and driver circuitry. Modules are
placed next to each other to form the matrix of an LED panel.
Network:
Multiple DDMS sets operated by the same control system.
Panelboard:
Circuit breaker box that distributes incoming power to internal components.
Pixel:
A group of LEDs that turn on and off to form the characters and graphics making
up the message content.
Power and Control Enclosure:
A cabinet that contains the equipment needed to operate
a DDMS set, all within an enclosure smaller than a typical traffic cabinet. Depending on
the type, power and control enclosures can be either wall or pole mounted.
Power Enclosure:
A cabinet with the same dimensions as the power and control
enclosure, but it contains only power equipment such as power supplies and the DC
terminal assembly. It pairs with a separate control enclosure. Power enclosures can be
either wall or pole mounted.
