Siemens 7ML19985AB01 instruction manual Logging, Capacity

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Under low flow conditions, a cut-off head (P45) can be entered to avoid totalizing flows occurring at or below the flow corresponding to the cut-off head.

LOGGING

The OCM-3 provides an extensive logging feature which can be viewed on the local display or retrieved via the serial communication link. The logging rate (P39) can be fixed or variable. The latter being useful in conserving logging space. The condition for variable logging is determined when selecting the logging rate.

Variable logging rate conditions are catagorized as : rate of change of flow, percent of maximum flow or percent of maximum head. Logging occurs at the normal (slower) rate while the condition is less than the setpoint (P40). If the condition exceeds the log rapid setpoint, the rapid rate of logging takes effect until the condition falls below the log normal setpoint (P41).

The associated setpoint units are : % change of maximum flowrate per minute, % of maximum flowrate and % of maximum head, respectively. The setpoints represent the absolute value of the rate of change; that is, for either increasing or decreasing flowrate. The OCM-3 does not recognize negative entries into P-40 and P-41.

Flow data is logged in 1/2 % increments from 0 to 110 % of maximum flow. Flows above 110 % are logged as 110 %. Truncation of flows to 110 % does not apply to daily totalization.

Log Capacity vs Rates
	rate	capacity
	1 min	31 days
	5	3 months
	15	9 months
	30	1 year
	60	1.5 years
	24 hr	2 years
e.g.	15 / 5	9 months max / 3 months min

Once the log is filled, the old data will be successively written over with the new data being logged.

The log can be examined via F14. Viewing of the log is done by task and by method. The viewing tasks are: daily flow totals, flow rates and min-max flow data for flow or temperature. The viewing methods are: by first entry, by last entry and by specified date. The scrolling keys are used to maneuver through the tasks, methods and time of day.

7ML19985AB01

OCM III

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Contents Open channel Unit Repair and Excluded Liability Contact Smpi Technical Publications at the following addressTable of Contents Operation Start UPGeneral Keypad Initial Start Up Fundamental Checks Maintenance Error Codes 100 Communications 101 7ML19985AB01 AppendicesOCM If you want to know about Read Product About thisShort OCM Specifications » range 20 or 4-20 mA » resolution» 20 to 50 C -5 to 122 F IP65 enclosureProgrammer » CE *, FM, CSA NRTL/CCabling Temperature SensorTransducer Output » Belden Communication SoftwareAuxiliary Input Outline and Mounting InstallationInstalling the OCM-3 OCM-3 Layout Customer device System DiagramOCM-3 Installing the Transducer Installing the Temperature SensorGround shield at OCM-3 only Basic Wiring Temperature Sensor Ground shield at OCM-3 onlyMA Output RelaysSynchronization DC Power Power ConnectionsAC Power Installing the Memory BACK-UP Battery Installing the ProgrammerDisconnect power before installing or replacing the battery Communicating VIA ComputerKeypad Start UPGeneral Initial Start UP OCM-3 is asking which language you prefer to communicateLanguage EnglishP0 language English P1 dimensional units Centimeters F13 auto zero calibration 160 Completed 7ML19985AB011141 24-hr. time114100 Enter new time F5 ddmmyyyy date October 12Fundamental Checks OCM Operation MemorySecurity UnitsFlow Calculation DisplayAbsolute vs. ratiometric = constantFor battery operation, set display lighting to off or auto DampingFor battery operation, have relays energizing on alarm Example For relay» 20 mA » P6 * flow rateFlow rate FAIL-SAFEFlow Rate and Totalizing Logging CapacityViewing the data log Time and Date TemperatureBlanking Emulation Mode ResetFlow Velocity Input Auxiliary Head InputVoltage Input Current Input As normal 7ML19985AB01100% head 4 m, enter 5 m Diagnostic AidsDC Output Security access required ‘D’ Parameter ListingVelocity Nominal target rangeOCM Keypad to mA output Enter security code Emulation mode‘F’ Parameter Listing OCM = centimetres ‘P’ Parameter ListingLinear Velocity Flowrate Volume = absolute = ratiometric Flow rate unitsGallons = imperial million gallons per dayOCM = 4-20 mA = 0-20 mA 7ML19985AB01 OCM OCM Units FixedVariable condition OCM ‘U’ Parameters for P3 Primary Element OCM = constant factor U1 = head U0 = exponent U1 = k factor P4 = 0 onlyReference Typical SHARP-CRESTED Weirs Typical Weir ProfilesKhafagi 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 Cv = velocity coefficient ¤ Refer to Operation \ Flow Calculation 7ML19985AB01BS-3680 Trapezoidal Flume BS-3680 U-Flume, P3 = BS-3680 U-FLUME = crest width = C = crest height = Cp = crest length = head H and p applied to CBS-3680 Finite Crest Weir = Ce x 2⁄3 ⎯⎯√2⎯g x be x he1.5 Where q = flow rate = approach width = Ce = crest width = K b = crest height= 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 Based on the Manning Formula = hydraulic radius = slope of hydraulic gradientRound Pipe U0 = maximum flume width, hmax PALMER-BOWLUS Flume U0 = maximum listed head, hmax Flume Universal Head vs FLOW, P3 = U0 = number of data points n, 4 toFlow, point A13 Head, point A14 Flow, point A15 Head, point A16Flow, 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 = channel top width, cm = head, cm = channel base width, cm = B b/d Where q = flow rate, l/sFor h ≥ d 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 Universal Area X VELOCITY, P3 = Typical open channelA10 = Universal Area X VelocityArea Head OCM Maintenance Error Codes Serial printer Customer’sComputer Protocol for the OCM-3 is as follows Baud rate 102DB-9 connector DB-25 connectorBipolar Current Refer to Cvcc Instruction104 DateP35 = 7, print interval set for 7 minutes 105 Utilities Software Programmer Remote OCM-3 programmingRemote OCM-3 display Local display 106 Typical OCM-3 Display value00.000000 99.12399.123000 7ML19985AB01 107# = 0 through Content of P5 Response109 Start data log down loadStop data log down load DB-25 connector 7ML19985AB01 Standard modemCable Computer Telephone lines Remote modem111 Establishing CommunicationConnect Ending Communication 112Rev