User manual

224
Time Synchronization
Minutes of deviation
The deviation of the time currently used for the measure-
ment from the GPS time is recorded by the XL2 in the log file
(123_Log.txt).
Add_To_Time
[ms]
GPS Status
[]
0.0 2.0
Meaning of the column “GPS Status”:
0.0 No GPS signal detected at the RCA input
1.0 GPS signal detected but signaled UNLOCKED
2.0 GPS signal LOCKED (OK)
The deviation Add_To_Time can only be determined currently
if the GPS status = 2 (locked). Otherwise, the last known er-
ror is used for the current log line. The Add_To_Time column
indicates “-.-” in case that there was no GPS time recognized
since the start of the device.
Example
The PPS signal is recorded with the XL2. For this, the input of
the XL2 from XLR to RCA can be set. The positive edge of the
recording should always be exactly to multiples of 10 seconds,
but in this case at 00: 35: 00,005:
_123_log.txt:
2017-10-05 09:49:58 00:34:58 -5.00 2.0 ---/---
2017-10-05 09:49:59 00:34:59 -5.00 2.0 ---/---
2017-10-05 09:50:00 00:35:00 -5.00 2.0 ---/---
2017-10-05 09:50:01 00:35:01 -5.00 2.0 ---/---
2017-10-05 09:50:02 00:35:02 -5.00 2.0 ---/---
In the log file, a correction value Add_to_Time of -5ms is re-
corded for this time position, so the corrected position of the
pulse is: 00: 35: 00,005 + (-5ms) = 00:35:00.
The state of the time synchronization can be seen in detail on
the NoiseScout Gateway website.