YSI 6 series User Manual page 184

650 MDS
 The GPS readings must be logged to 650 memory from the 650 Run display along with sonde sensor
readings. This means that you must have a sonde attached to your 650 via the 6115 cable in order to
log GPS readings. Logging of GPS readings is not supported without sonde attachment even though
these readings can be viewed in the Status Bar with no sonde attached.
 If your want to log the GPS readings to 650 memory along with sonde sensor readings at a particular
location, you must make certain that the Store Lat and Long option is active in the Logging setup
menu of the 650.
Once these conditions are met, follow the instructions in Section 3.5.3 above for logging of sonde sensor
readings to 650 memory. The GPS readings will automatically be added to the file at the sample interval
selected for the sonde readings.
GPS readings stored in 650 memory will remain as part of the sensor data file that can be viewed from the
650 display and/or uploaded with the data file for analysis in EcoWatch for Windows. Latitude and
longitude are, however, displayed somewhat differently by the 650 and EcoWatch as noted below:
 For both display formats, the GPS are indexed relative to the point where the Greenwich Mean Time
line crosses the equator.
 For the 650 Status Bar, readings are displayed in degrees and then decimal minutes relative to this
point with actual "N" (north), "S" (south), "E" (east) and "W" (west) designations relative to the index
point.
 When analyzing data in EcoWatch, the user will have the choice of two formats, decimal degrees (e.g.,
47.5400 degrees) or degrees/decimal minutes (e.g., 47
characters ("N", "S", "E", and "W") are NOT used. Instead, points north and east of the index point
are designated as positive, while points south and west are designated as negative.
These criteria mean that the GPS coordinates of Yellow Springs, Ohio, USA are approximately 39
o
latitude and -83 54.13' longitude as read in EcoWatch, but N 39
650.
YSI Environmental Monitoring Systems Operations Manual
o
32.400'). For EcoWatch, alpha directional
o o
47.33' W 83 54.13' as displayed by the
Section 3
o
47.33'
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