Abekas AirCleaner, Руководство пользователя

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AirCleaner • User Guide 59
4. Operations
Reaction Time
Screener 2
TAP OUT
screening monitor.
But Screener 2 continues to hold down his/her panic button for an additional two
seconds, releasing it only after the end of the violation (
d
); the entire violation is
therefore masked at the video output from AirCleaner.
Drawback of Very Large Reaction Time
Although it may be tempting to program an extremely large Reaction Time, since
larger may seem to be “better,” there is one pitfall of doing so: a very large reaction
time will cause the masking trigger to be advance so far ahead of the actual violation,
that program material that shouldn’t be masked will be masked.
For example, imagine the Video Reaction Time is set to a very large value of 35:00
seconds. Using an otherwise identical example as used earlier in the Theory of
Operation discussion (
refer to “Theory of Operation” on page 46
above), let’s take a
look at what the very large reaction time will do.
1.
TIME 05:00 |
The first frame of the violation appears on the Screener’s video
monitor and is presented to AirCleaner’s video input. However, due to human
visual reaction delay, the Screener has not yet pressed the VIDEO panic button.
Figure 4-20. Overly Large Reaction Time: Elapsed time of 05:00 seconds