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Date of Installation
The date, according to the Engineer's daily record of construction, that the equipment
begins normal continuous operation.
Delayed Output
A detector feature that enables a detector to delay its output for a predetermined
length of time after the vehicle enters the detection zone.
Density
A measure of the concentration of vehicles, stated as the number of vehicles per mile
per lane.
Detection (Vehicle, Pedestrian)
A registration of a demand by vehicles or pedestrians for traffic right-of-way at a
controller assembly.
Detector
A device for indicating the presence or passage of vehicles or pedestrians.
Detector Amplifier (Detector Unit)
An electronic device that converts the signal generated by an associated sensor or
sensors to an output usable by a controller or other device.
Detector Loop
A sensing element of a detector that consists of one (1) or more loops or turns of wire
embedded in the pavement to form the inductive portion of a tuned circuit.
Detector Memory
A feature of a controller assembly that retains a detection for future utilization by the
assembly. Also simply called Memory. When in operation, it is referred to as Locked
Detector Memory. When disabled, it is referred to as Non-Locking Detector Memory.
Detector Mode
A term used to describe the operation of a detector channel output when a presence
detection occurs.
1.
Pulse Mode - Detector produces a short output pulse when detection occurs.
2.
Presence Mode (Continuous Presence Mode) - Detector output continues if any
vehicle remains in the field of influence.
3.
Limited-Presence Mode - Detector output continues for a limited period of time if
any vehicle is in the field of influence.
Digital Controller
A controller which utilizes digital timing.
Definitions
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Charlotte Department of Transportation