700- LT1-Man Rev 8 09 Feb 2021
Page 40/60
6.2
LT1-CELL: CALCULATING START TIME FOR SDI-12 AND COUNTER SENSORS
This is optional and used for those agencies with a requirement for data readings as close as
possible before transmission. If you do not require this level of timing, you can leave the start time
at the default setting or set it to the desired minute from which you want the sample readings
started.
For a sensor to collect information and have the most recent readings available for the scheduled
transmission, the sampling start time must be determined as follows:
Sample start time = a - (b+c+d)
In which:
a) Transmission interval
b) Time to take readings (found by entering the measurement command from
transparent mode – refer to section 6.3.1 and the sensor’s manual)
c) Time to buffer the readings
d) Safety buffer (to ensure no truncation of data occurs during buffering)
Example:
Sample Interval: 5 minutes
a) Transmission interval: Hourly at 5 minutes after the hour
b) Time to take readings: 10 seconds
c) Time to buffer the readings: 5 seconds
d) Safety buffer: 2 seconds
Using the example figures: Start time = 00:05:00 – (10 secs+5 secs + 5 secs + 2 secs)
Start time = 00:05:00 – 00:00:27
Start time = 00:04:38
Therefore, with a sample interval of 5 minutes, samples are taken at 00:04:38,
00:09:38, 00:14:38, 0019:38 etc. so the hourly transmission will include the last logged
data point which was taken at 27 seconds before the transmission.
Содержание LT1-CELL-VZ
Страница 6: ...iv D 6 CONFORMITIES 58 D 7 RF EXPOSURE 59...
Страница 61: ...700 LT1 Man Rev 8 09 Feb 2021 Page 55 60...
