Glossary
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Glossary
Address:
Identification number assigned to each sign in a network, set through the front
panel interface. The central controller uses the address to differentiate between signs
connected on the same network. Signs on the same network cannot have the same
address.
Central Controller:
Software system that can control displays remotely. This hardware
device 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.
Column:
Vertical line of pixels.
Dynamic Message Sign (DMS):
An electronic message display used on roadways to give
travelers information about traffic conditions. Such displays may inform of events like
traffic congestion, accidents, incidents, or roadwork zones.
Eyebolt (Lifteye):
Heavy steel bolt with a loop attached to the top of the display cabinet
for lifting.
Isolation Board:
Interface between the power supply and the redundant power bus. It
provides isolation between the redundant power bus and a failed power supply.
Light Emitting Diode (LED):
Low-energy, high-intensity lighting units. Multiple, closely
spaced LEDs form a pixel on the DMS display.
Matrix:
Visible area on a display, measured in rows and columns of pixels.
Module:
Component containing an array of LED pixels and pixel driver circuitry. Modules
are placed next to each other to form the matrix of the display.
NTCIP:
National Transportation Communication for ITS Protocol.
Panelboard:
Circuit breaker box that distributes incoming power to the internal display
components. A single panel unit may include buses, automatic overcurrent devices, and
switches for light, heat, and power.
Pixel:
A group of LEDs that turn on and off to form the characters and graphics making
up the message content.
Power Supply:
Unit that converts incoming AC power to DC power as required by several
components within the display.
Power Supply Enclosure:
2–4 power supplies that provide redundant power to the display
modules.
Relay:
An electromechanical or semiconductor switch in which a current or voltage
applied across one port or terminal controls electrical currents or voltages that appear
across another terminal or terminals.
Row:
Horizontal line of pixels.
