Siemens 7ML19985AB01 instruction manual Cv = velocity coefficient

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BS-3680 TRAPEZOIDAL FLUME, P3 = 3
‘U’ parameters required *			‘U’ parameters calculated **
U0	= approach width	B	U5	= Cv
U1	= throat width	b	U6	= Cd
U2	= hump height	p	U7	= Cs
U3	= throat length	L	U8	= A
U4	= slope	m

*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 Cs/Cscal x Cd/Cdal x Cv/Cvcal x (h/hcal)1.5

where :
q = flow rate	Cscal = shape coefficient for maximum head
qcal = flow rate at maximum head	Cv = velocity coefficient
h = head	Cvcal = velocity coefficient for maximum head
hcal = maximum head	Cd = discharge coefficient for head
Cs = shape coefficient for head	Cdcal = discharge coefficient for maximum head

¤Refer to Operation \ Flow Calculation.

7ML19985AB01

OCM III

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Contents Open channel Contact Smpi Technical Publications at the following address Unit Repair and Excluded LiabilityTable of Contents General Keypad Initial Start Up Fundamental Checks Start UPOperation Appendices Maintenance Error Codes 100 Communications 101 7ML19985AB01OCM Short About thisIf you want to know about Read Product OCM » range 20 or 4-20 mA » resolution Specifications» 20 to 50 C -5 to 122 F IP65 enclosure» CE *, FM, CSA NRTL/C ProgrammerTransducer Temperature SensorCabling Auxiliary Input Communication SoftwareOutput » Belden Installing the OCM-3 InstallationOutline and Mounting OCM-3 Layout OCM-3 System DiagramCustomer device Installing the Temperature Sensor Installing the TransducerGround shield at OCM-3 only Basic Wiring Temperature Sensor Ground shield at OCM-3 onlyRelays MA OutputSynchronization AC Power Power ConnectionsDC Power Installing the Programmer Installing the Memory BACK-UP BatteryDisconnect power before installing or replacing the battery Communicating VIA ComputerGeneral Start UPKeypad OCM-3 is asking which language you prefer to communicate Initial Start UPLanguage EnglishF13 auto zero calibration 160 Completed 7ML19985AB01 P0 language English P1 dimensional units Centimeters24-hr. time 1141114100 Enter new time F5 ddmmyyyy date October 12Fundamental Checks OCM Memory OperationSecurity UnitsDisplay Flow CalculationAbsolute vs. ratiometric = constantDamping For battery operation, set display lighting to off or autoExample For relay For battery operation, have relays energizing on alarm» 20 mA » P6 * flow rateFlow Rate and Totalizing FAIL-SAFEFlow rate Capacity LoggingViewing the data log Blanking TemperatureTime and Date Reset Emulation ModeAuxiliary Head Input Flow Velocity InputVoltage Input Current Input As normal 7ML19985AB01DC Output Diagnostic Aids100% head 4 m, enter 5 m ‘D’ Parameter Listing Security access requiredVelocity Nominal target rangeOCM ‘F’ Parameter Listing Enter security code Emulation modeKeypad to mA output OCM Linear Velocity ‘P’ Parameter Listing= centimetres = absolute = ratiometric Flow rate units Flowrate VolumeGallons = imperial million gallons per dayOCM = 4-20 mA = 0-20 mA 7ML19985AB01 OCM OCM Variable condition FixedUnits OCM ‘U’ Parameters for P3 Primary Element OCM Reference U0 = exponent U1 = k factor P4 = 0 only= constant factor U1 = head Typical Weir Profiles Typical SHARP-CRESTED WeirsKhafagi Venturi Typical Parshall Flume Typical Leopold Lagco ‘U’ parameters required ‘U’ parameters calculated BS-3680 Rectangular Flume = crest width = Cv = crest height = Cd = crest length = a BS-3680 Round Nose Horizontal Crest Weir ¤ Refer to Operation \ Flow Calculation 7ML19985AB01 Cv = velocity coefficientBS-3680 Trapezoidal Flume BS-3680 U-Flume, P3 = BS-3680 U-FLUME = head H and p applied to C = crest width = C = crest height = Cp = crest lengthBS-3680 Finite Crest Weir = approach width = Ce = crest width = K b = crest height = Ce x 2⁄3 ⎯⎯√2⎯g x be x he1.5 Where q = flow rate= gravitational acceleration = crest width He = effective head h + Kh = head Kh = 1 mmBS-3680 Thin Plate Rectangular Weir U0 = notch angle Alpha U1 = Ce BS-3680 Thin Plate V-NOTCH Weir U0 = crest width b Rectangular Weir Contracted = hydraulic radius = slope of hydraulic gradient Based on the Manning FormulaRound Pipe U0 = maximum flume width, hmax PALMER-BOWLUS Flume U0 = maximum listed head, hmax Flume U0 = number of data points n, 4 to Universal Head vs FLOW, P3 =Flow, point A15 Head, point A16 Flow, point A13 Head, point A14Flow, point A17 Head, point A18 Flow, point A19U0 = channel width B U1 = area h Rectangular Area X Velocity = head, cm = flow velocity, cm/sec Trapezoidal Area X Velocity For h ≥ d = B b/d Where q = flow rate, l/s= channel top width, cm = head, cm = channel base width, cm Modified Trapezoidal Area X Velocity U0 = base diameter D U1 = area h Channel Area x Velocity U0 = conduit diameter U1 = area h Circular Area X Velocity GULL-WING Area X VELOCITY, P3 = Gull Wing Area X Velocity EGG-SHAPED Area X VELOCITY, P3 = EGG-SHAPED Area X Velocity Typical open channel Universal Area X VELOCITY, P3 =Area Head Universal Area X VelocityA10 = OCM Maintenance Error Codes Computer Customer’sSerial printer 102 Protocol for the OCM-3 is as follows Baud rateDB-25 connector DB-9 connectorBipolar Current Refer to Cvcc InstructionP35 = 7, print interval set for 7 minutes Date104 Remote OCM-3 display Local display Utilities Software Programmer Remote OCM-3 programming105 106 Display value Typical OCM-300.000000 99.12399.123000 7ML19985AB01 107Response # = 0 through Content of P5Stop data log down load Start data log down load109 Standard modem DB-25 connector 7ML19985AB01Cable Computer Telephone lines Remote modemConnect Establishing Communication111 112 Ending CommunicationRev