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2021-06-24
CU-M001 User manual
Note
: The stored calibration settings may be overwritten in some software upgrades or if master
reset is performed. We advise recording the values somewhere, just in case.
Doppler systems typically have a calibration factor within 10 % i.e. measured 9 kn, real 10 kn.
During and after each leg a distance will be shown in 0.001NM resolution. This shows the measured
distance using the current calibrated values. This information can be used to measure the performance
of the system. The SOG (Brown) should be within 2% of the set distance on each leg. The STW
should be within 2% on the average of 2 legs (These percentages can only be meausred after at
least one succesful calibration
If the resulting factors look correct, click ‘Save’ to transfer the data into the calibration number on
the right.
If you wish to perform a second calibration at another speed, move to the next calibration number
and repeat.
Avg measured STW. The Water Speed measured in leg
Avg measured SOG. The bottom Speed measured in leg
Calcul real speed. The Real speed calculated by distance set / time taken
GPS AVG the average speed during the leg (Max and Min are below) This should be within 0.2 kn
the real speed, if not the vessel has not sailed evenly.
Leg Validity. % of accepted measurements. This will fall if quality is bad or the bottom is lost. And
will change colour. If red or orange, redo the calibration.
GPS The distance the vessel has sailed based on the GPS input
Water, the distance the vessel has sailed through water based on the current
calibrations (this will be more or less than GPS depending on the water current)
Ground, The distance sailed over the sea bed, based on the current calibrations.
These values are good for validation of the systems accuracy, Ground and GPS
should be the within 2% E.g. GPS=1.000 Ground = 0.980 to 1.020
