Siemens 7ML19985AB01 instruction manual = crest width = Cv = crest height = Cd = crest length = a

BS-3680 Round Nose Horizontal Crest Weir, P3 = 2

‘U’ parameters required *			‘U’ parameters calculated **
U0	= crest width	b	U3	= Cv
U1	= crest height	p	U4	= Cd
U2	= crest length	L	U5	= A

*obtain from manufacturer’s specifications.

**calculated by OCM-3. May be viewed by accessing ‘U’ parameter.

Reference

ABSOLUTE CALCULATION, P4 = 0¤
For flows that can be calculated by the equation:
q = (2/3)1.5 x g0.5 x Cv x Cs x Cd x b x h1.5
where : q = flow rate	Cv = velocity coefficient
g = gravitational acceleration	Cs = shape coefficient
b = throat width	Cd = discharge coefficient
h = head
RATIOMETRIC CALCULATION, P4 = 1¤
For flows that can be calculated by the equation:
q = qcal x Cd/Cdcal x Cv/Cvcal x (h/hcal)1.5

where : q = flow rate

qcal = flow rate at maximum head h = head

hcal = maximum head Cv = velocity coefficient

Cvcal = velocity coefficient for maximum head

Cd = discharge coefficient for head

Cdcal = discharge coefficient for maximum head

¤Refer to Operation \ Flow Calculation.

7ML19985AB01 OCM III 60