Wavetronix Click 500 (programmable controller) (CLK-500) - User Guide - Manual (Page 89)

88 CHAPTER 9 • CLICK 512
Note
If a vehicle exceeds the anticipated maximum speed and length, then the detection
event may not be generated until the vehicle’s ETA is less than the desired value. In
this case, the output will activate upon reception (without any additional delay).
In order to trigger an ETA to a sign:
1 Select the Automatic (English) configuration options.
2 Specify the corresponding setback distance in feet. In this case, the setback distance
is from the location of the SmartSensor HD unit to the location of the warning sign.
3 Specify the ETA in milliseconds.
4 Specify the duration in milliseconds.
Note
If your SmartSensor HD unit is configured in Metric units, select the Automatic (Met-
ric) configuration option. In this case, the setback distance is specified in decimeters
instead of feet.
Since vehicles travel at different speeds, the amount of time from when the front edge of the
vehicle enters the beam until it reaches the warning sign is variable. In addition, the amount
of time the vehicle is in the beam is also variable (based upon vehicle speed and length).
The following diagram illustrates the basic timing of this option as a series of six steps. Some
portions of the timing are variable and others are fixed.
variable
L_ft / V_fps
fixed
1 s
variable
ETA (ms)
Duration (fixed)
1 2 3 4 6 5
variable
Time to Sign = SetbackDistance_ft / V_fps
Figure 9.5 – Diagram for ETA Timing Method
1 Front edge of vehicle enters beam.
2 Back edge of vehicle leaves beam. The time from point 1 to point 2 is variable and is
based on the length and speed of the vehicle.
3 Detection event is generated one second after the vehicle leaves the beam. This one-