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USE
Turn on the power to the PNL18 to make it operational. The display will count up to from
1 to 10 and then blank out. The sign is now fully operational.
If the rotary speed switch is enabled (see later section on configuration), turn the speed
switch to the desired position (0 through 7) determined by the speed limits on the road to
set the low-speed display cutoff, violator display flashing speed, and the high-speed
display cutoff.
Typically, users set the violator flashing speed at or just above the speed limit on the road
and the high-speed display cutoff at a speed sufficiently above the speed limit to capture
most of the speeding traffic but not high enough to encourage “racing against the radar”.
For example, for a 25mph speed limit road, the violator limit may be set to 26 mph and
the low and high cutoffs will be set 15 mph below and above this value respectively. The
exact values are of course left to the judgment of the user.
No other action is required. The PNL18 will display the measured speed when an
incoming vehicle is detected between the low-speed and high-speed limits. The display
will blink at about 1.4Hz rate if the measured speed is above violator speed. This
indicates to the driver that they are driving above the speed limit.
If the white LED cluster is populated (this is the default, but you may choose to have it
removed), and enabled through the software configuration - it will strobe at a 10Hz rate.
The strobe can also be configured to blink at 1.4 Hz rate when activated.
Finally, if the vehicle speed is above the high-speed display cutoff, the display will be
blanked. This prevents drivers from “racing against the sign” (trying to see how high a
speed they can display). The strobe may be configured to stay active or go blank above
this speed.
As long as the radar is tracking a target between the low-speed cutoff and the high-speed
cutoff, the radar will transmit the speed in user selected ASCII format over the serial
interface. This may be observed via our PC based configuration tool or captured by an
external user provided controller board. Monitoring or capturing this speed is not
required for normal operation of the speed sign.
Serial output is affected by low, high, and violator speed configuration in the same way
as the display panel.
