UCM Calibration
FlexPI Product Guide
Page 33
Setting the cut Count and time Window
The default settings for the cut Count and time Window are based on years of field experience.
However, if the security regulations at your facility mandate a specific cut Count and time Window,
then adjust the settings accordingly and monitor the system for nuisance alarms. To customize
these parameters for your site, set the cut Count and time Window according to the probability of
nuisance impacts occurring within a given timeframe. For example, if nuisance impacts can occur,
but not in rapid succession, then the Cut Count can be set to 2 with a short Time Window. If
nuisance impacts should never occur, a Cut Count of 1 is recommended so that an intruder cannot
defeat the system by waiting between impacts.
The Cut Profile
The Cut Profile is an advanced parameter that is used to prevent an intruder with indepth
knowledge of the sensor from defeating the system by waiting a specific amount of time between
impacts. At the default setting, 20% of the Window setting is added to the time remaining in the
Window after each impact. Raising the Cut Profile increases the time added to the time Window
each time an impact is recorded. Lowering the Cut Profile decreases the time added to the time
Window each time an impact is recorded.
Setting the Climb Alarm parameters (sustained attack)
1.
Start recording a UCM Magnitude response plot tool, and perform the simulated sustained
attack scenario along the protected surface.
2.
If the attack simulation does not cause an alarm, lower the Climb Alarm Threshold and repeat
the tests.
3.
Repeat this process until the simulated attack always causes a Climb alarm.
4.
Once the Threshold is set, monitor the system for nuisance alarms. If the nuisance alarm rate
(NAR) is unacceptable, try to determine and correct the source. Otherwise, raise the
Threshold and continue monitoring the NAR.
CAUTION
If the Cable Gain setting is adjusted it will also affect the Climb Alarm
Threshold. Retest, and if required, adjust the Climb Alarm Settings
after changing the Cable Gain.
Note
Save the UCM file and download the new settings to the processor
after making configuration changes with the UCM.
Note
If the Threshold is at or very close to the minimum value, and the
simulated attack is still not causing an alarm, try raising the Gain one
level, reset the Climb Threshold to 10, and repeat the tests.
If the Threshold is at, or close to the maximum value, and the
nuisance alarm rate is unacceptable high, lower the Cable Gain
setting one level, reset the Climb Threshold to 10, and repeat the
tests.
If performing the above does not correct the situation, you will have to
redeploy the sensor cable using reduced cable spacing, while
ensuring that the cable is in close contact with the protected surface.
Repeat the entire calibration process after modifying the sensor cable
layout.
