Milltronics OCM II PL-269, Instruction Manual

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Example 1
BS-3680 triangular weir, when P2=6 is entered, the OCM II will switch to the list of unit parameters required for
that type of flow calculation. If the prompting sequence is followed, none of the unit parameters will be
inadvertently omitted. The OCM II will switch back to "P" parameters once all necessary "U" parameters have
been entered.
a) U0 = Q
cal
This is the calibration flow, i.e. the flow that is expected to occur when the liquid level is at h
cal
, the calibration
head. It may be entered in any engineering units and may be in units per second, units per minute, units per
hour or units per day.
In this case, h
cal
= 38 cm so that Q
cal
= 0.031273 m
3
/ s.
b) U1-time units of Q
cal
We have chosen to have our calibration in flow units per second so we must enter U1 = 0.
c) U2 = h
cal
This is the head at which the calibration flowrate defined by U1 and U2 will occur. In our case it is 38 cm.
d) U3 = The angle of the weir
We will also need to enter the angle of the weir’s V-notch which is 28 degrees 4 minutes or 28.06666 degrees.
We shall use U3 = 28.07.
We shall now enter these values beginning with U0, which at this point is displayed in the prompt window.
U0 = 0.03127 Enter [0.03127] [E]
U1 = 0 Enter [0] [E]
U2 = 38 Enter [38] [E]
U3 = 28.07 Enter [28.07] [E]
Now the display in the prompt window switches to P3 so that the next "P" parameters can be entered.
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