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Velocity
P860 Sound Velocity
This parameter allows for the velocity of sound to be changed according to
the atmosphere the transducer is operating in. By default the velocity is set
for sound travelling in air at an ambient temperature of 20 degrees
centigrade. Default = 342.72m/sec
The following two parameters can be used to re-calibrate the Sound
Velocity (P860), when the acoustic beam from the transducer is travelling
through mediums other than air or when there are variations of temperature
between the transducer face and the material level.
To obtain best results calibration should be carried out when the level is as
near empty as possible and when any vapour present has stabilized.
P861 Cal.Dist 1
This parameter is used to re-calibrate the speed of sound for Xducer 1
P862 Cal.Dist 2
This parameter is used to re-calibrate the speed of sound for Xducer 2, when
P100 = 4 (Avg. Level), 5 (Differential Level) or 6 (Vol Avg.)
With the material at a steady level, view the value of P861 or P862, which
will indicate the current distance as calculated by the Ultra 5 with respect
to the current Velocity P860. Physically measure the distance from the face
of the transducer to the surface of the material level and enter this value,
in Measurement Units P104 and P860 will be automatically updated to
compensate for any difference between the displayed and entered values.