Some Standard Features of Reno A&E’s LCD Traffic Detectors
- “Custom Back Lit LCD” screen displays the complete status and function settings of the detector with excellent visibility.
- “Enhanced User Interface” allows for all functions to be programmed from the front panel LCD menus. No more removing the detector to change function settings.
- “Loop Inductance Change Bar Graph” with eight segments shows the change of loop inductance to verify ideal sensitivity level setting.
- “Liquid Crystal Display” displays loop frequency, loop inductance, and -ΔL/L Values. The detector functions like a loop analyzer.
- “Loop Failure Memory Log” displays the total number of loop failures since the last reset or power up and helps diagnose intermittent systems.
- “Loop Fail Diagnostics” provides an indication of shorted loops (L lo) and open loops (L hi).
- “LED Indicator Status” has one LED per channel and indicates call output, extension and delay timers, or failed loops.
- “Audible Detect Signal” indicates actual occupancy of the loop detection zone. This feature allows a technician to watch the detection zone on the street and confirm correct detector operation without having to look at the detector display as well.
Programmable Features of Reno A&E’s LCD Traffic Detectors
- Nine sensitivity levels that are displayed on the LCD. A unique bar graph displayed on the LCD makes it easy to quickly set sensitivity at the optimal level for any loop/lead-in network situation. There are nine selectable sensitivity levels per channel, plus Continuous-Call and Channel-Off.
- CONTINUOUS-CALL: When set to the Continuous-Call state, the channel output is continuously in the Call state regardless of the presence or absence of vehicles over the loop. The loop oscillator is disabled when in the Continuous-Call state. This state is indicated by “CALL” flashing on the LCD. This option is selected from the Sensitivity menu in Program Mode and is useful for checking controller response and other troubleshooting activities.
- CHANNEL-OFF: When set to the Channel-Off state, the channel output is continuously in the No-Call state regardless of the presence or absence of vehicles over the loop. The loop oscillator is disabled when in the Channel-Off state. This state is indicated by “OFF” flashing on the LCD. This option is selected from the Sensitivity menu in Program Mode and is useful for checking controller response and other troubleshooting activities.
- Eight frequency levels that are displayed on the LCD. The LCD screen displays the actual loop operating frequency (in kilohertz) for each setting which makes it easy to quickly identify and eliminate crosstalk in the most difficult intersections. There are eight selectable loop frequency settings per channel (normally in the range of 20 to 100 kiloHertz). The actual loop operating frequency is a function of the loop / lead-in network and the components of the loop oscillator circuit.
- Presence or pulse modes of operation.
One of two mutually exclusive modes of operation for each channel is selected in the Program Mode:
- PRESENCE MODE: Provides a Call hold time of at least four minutes (regardless of vehicle size) and typically one to three hours for an automobile or truck.
- PULSE MODE: An output Pulse of 125±10 milliseconds duration is generated for each vehicle entering the loop detection zone. Each detected vehicle is instantly tuned out if it remains in the loop detection zone longer than two seconds. This enables detection of subsequent vehicles entering the loop detection zone. After each vehicle leaves the loop detection zone, the channel returns to full sensitivity
within 0.5 seconds.
- 0 to 255 seconds delay timing.
Each channel’s Call Delay is adjustable from 0 to 255 seconds in one second steps. Call Delay time starts counting down when a vehicle enters the loop detection zone. The remaining Call Delay time is continuously displayed on the LCD. Whenever a Phase Green Input (call delay override) signal (pin 1 or 2) is active, the Call Delay function for that channel is aborted and the Call Delay time is forced to zero.
- 0 to 25.5 seconds extension timing.
Each channel’s Call Extension is adjustable from 0 to 25.5 seconds in 0.1 second steps. Extension time starts counting down when the last vehicle clears the loop detection zone.
The remaining Extension time is continuously displayed on the LCD. Any vehicle entering the loop detection zone during the Extension time period causes the channel to return to the Detect state, and later, when the last vehicle clears the loop detection zone, the full Extension time starts counting down again.
NOTE: See Option 3, Call Extension Control, on page 34 for an alternate mode of operation for Call Extension.
- 1 to 999 seconds maximum presence timing.
Each channel’s Max Presence timer is adjustable from 1 to 999 seconds in one second steps, plus OFF. The Max Presence function is used to limit presence time by automatically resetting a channel. If this function is enabled (on), the Max Presence timer begins counting down when a Call is initiated and the remaining time is continuously displayed on the LCD.
If the loop becomes vacant before the Max Presence timer reaches zero, the Call is dropped and no automatic reset occurs. If the End-Of-Green (EOG) function is not enabled
(off) and the Call is still present when the Max Presence timer reaches zero, the channel is then automatically reset. If the EOG function is enabled (on) and the Call is still present when the Max Presence timer reaches zero, the channel enters a Wait state. The Wait state continues until either the loop becomes vacant or the Phase Green Input signal for the channel transitions from green to not green with the Call still present. If the loop becomes vacant first, the Call is dropped and no automatic reset occurs. If the Phase Green Input for the channel transitions from green to not green while the channel is in a Wait state, the channel is automatically reset. The Phase Green Inputs are also called Call Delay Overrides.
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