DCT Antares SB, Руководство пользователя

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4.8. THE TIME AND DISTANCE CRITERIA
set the signal low whenever the vehicle’s speed is below the limit. Up to
10 speed limits may be defined, so there are 10 speed signals (
S00 - S09
)
available to be used on an event’s definition.
To create the speed limit
00
having a value of 55mph send to the unit:
Example
>
SGS0010550
<
Now an event can be created so any time the vehicle exceeds 55mph event
33 is generated:
>
SED33NV0;S00+
<
A configuration may be created so a warning to the driver is given via
a LED indicator before actually generating the event. See the
Scenarios
and Examples section for this.
4.8 The Time And Distance criteria
Up to 10 Time And Distance (T&D) criterion can be defined. Time And
Distance definitions are covered on the
TD
TAIP message.
A T&D signal attached to an event generates a T&D-like report whose
frequency changes according to the vehicle’s displacement. With this, the
unit increases the report frequency when the vehicle is moving (accumulat-
ing traveled distance) and decreases it when the vehicle is not moving. This
is more efficient than having the unit report by a
time-only criteria were
almost all of the reports triggered when the vehicle is not moving are not
relevant.
The unit can also be configured with a time-only criteria. Note:
How does this criteria work ?
First, the report has to be triggered by a distance threshold that tells the
unit to send a report whenever the accumulated distance exceeds this value.
This
distance-only scheme has two problems:
1. What if the vehicle goes too fast and/or the distance threshold is low
?. It will report too frequent.
2. What if the vehicle moves too slow and/or the distance threshold is
large ?. Or worse, what if it does not move at all?. It will report very
few times or may never report.
To solve this problem the distance-only report is improved with a Time
and Distance report that adds two controlling parameters for the Distance
threshold . These parameters are the Minimum time between reports and the
Maximum time between reports .
The Maximum time between reports takes control of the report when the
unit has not exceeded the Distance threshold for a long time. So this value
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