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Application 1 Enclosed Tank 
Whilst this application may seem easy, you can get problems with the unit 
observing  multiple  echoes.  If  the  secondary  or  tertiary  echoes  are  of  a 
sufficient signal strength then fluctuating readings could occur. 
This could be the case in a liquid vessel with a domed top that can re-focus a 
secondary  echo  magnifying  it to  a  height that could  cause  problems. See 
below. 
 
 
 
 
 
 
 
 
 
 
 
 
   
 
 
At a certain ‘focal length’ the secondary echo can become problematic. 
 
If this is the case you may find the unit reading a level that is twice the actual 
distance. 
 
Follow the procedure below to cure the problem. 
 
Software Version 7.1.8 0nwards, simply enter the programme Mode and go to 
P102 (Material) and select option 3 = Closed Tank, the following parameters will 
then be set, automatically, to the values detailed below: 
 
Software Versions prior to 7.1.8 will need to have the following parameters 
changed manually.  
 
To manually change, enter the service code (552621) and change the following 
parameters.