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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 parameter 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 
With the material at a steady level, view the value of P861 or P862, which 
will  indicate  the  current  distance  as calculated  by the  FlowCERT LITE 
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. 
Stability Parameters 
Damping 
Damping  is  used  to  damp  the  display,  to  enable  it  to  keep  up  with  the 
process but ignore minor surface fluctuations. 
P870 Fill Damping 
This  parameter  determines  the  maximum  rate  at  which  the  unit  will 
respond  to  an  increase  in  level.  It  should  be  set  slightly  higher  than  the 
maximum vessel fill rate. Default = 10m/min 
P871 Empty Damping 
This  parameter  determines  the  maximum  rate  at  which  the  unit  will 
respond  to  a  decrease  in  level.  It  should  be  set  slightly  higher  than  the 
maximum vessel empty rate. Default = 10m/min