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RATIOMETRIC 
V-Notch Angle Weir (Non-BS 3680) 
If the flow calculation is to be ratiometric P702 = 2 the flow will be 
calculated using the formula: q= q
cal  
(h+kh/h
cal
+kh)
2.5
 
Where:  q     = flowrate        
q 
cal  
= flowrate at maximum head P705     
h     = head      
kh   = compensated head 
 
Universal Calculations 
Point of Measurement 
The transducer must be above the maximum head P704 by at least the near 
blanking distance P107.  
For  all  Universal  calculation  applications,  the  point  at  which  the  head  is 
measured should be chosen such that the surface of the liquid is not effected 
by turbulence. 
Calculations  
ABSOLUTE 
Universal Head Vs Flow 
If the flow calculation is to be absolute P702 = 1 the flow will be calculated 
using the formula:  q = q(h)
 
Where:  q  = flowrate             
q(h)  = flowrate for head    
The desired number of Breakpoints, (P730 - P793) are to be entered in 
pairs in values of head and corresponding flow. (Minimum of 2 pairs of 
Breakpoints is required).