7.1 Report Exceptions
Several conditions may prevent the position report from being sent at the expected time. These conditions
include:
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Delayed position reports – Several environmental factors may cause a position report to be delayed
temporarily. If a position report is delayed, then a new position report will be calculated and trans-
mitted when the environmental factor has been cleared.
o
Extreme temperature – If the temperature is outside of the recommended operating range of
the Spider AT, then the GPS receiver and GSM modem will not be powered on. The report will
be delayed until the temperature is within the product’s acceptable temperature range.
o
Marginal temperature - If the temperature is marginal, then there is a minimum time interval
required between reports to insure that the battery is sufficiently recharged to successfully
transmit the position report. If a position report is scheduled before this minimum time inter-
val has expired, then the report will be delayed until the minimum time interval has expired.
o
Low voltage – If the battery voltage is too low, then the position report will be delayed until
the battery voltage is above the product’s minimum battery threshold. This delay provides an
opportunity for the battery to recharge.
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No GSM coverage – If the Spider AT 3000 cannot register on the GSM network or cannot transmit
the position report, then the report is stored in internal memory. The stored message will be sent at
the next opportunity when the GSM modem is powered on to transmit the next scheduled position
report. A maximum of 10 messages will be stored.
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Time of day reporting without RTC – The Spider AT 3000 uses valid GPS data to automatically set the
RTC time. If the Spider AT 3000 has not detected valid GPS data since the last activation, then the
RTC time will not be accurate. If the Spider AT 3000 is configured to use the Static Asset Monitoring
with Time-of-Day Reporting service and the RTC time is not accurate, then the Spider AT 3000 will
still report at the desired time intervals, but it will report at a random day/time. For example, it will
report each day but not at the desired time of day.
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Delta time reporting drift – The time between position reports (unless using Time-of-Day) is a delta
time interval since the last report. This time interval does not include the time to gather the position
data and register on the GSM network. The GPS receiver acquisition and GSM registration times vary
and will cause the time between reports to be several minutes longer than the specified reporting
time interval. For example, if the Spider AT 3000 is configured to report once per day and the device
is activated at 12:00 PM on Monday, then the next several reports will occur approximately at 12:05
PM Tuesday and then 12:10 PM on Wednesday.
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UDP packet lost in network – The Spider AT 3000 uses the UDP data transport protocol. Although the
vast majority of position reports will be delivered successfully to the server, a small number of posi-
tion reports may be dropped in transit by the GSM or internet network.
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