Siemens 7ML19985AB01 instruction manual Blanking, Temperature, Time and Date

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BLANKING

Blanking is used to ignore the zone in front of the transducer where ringing or other false echo is at a level that interferes with the processing of the true echo. The minimum blanking is factory set, but can be overridden by entering the desired distance into P47.

Ringing is the inherent nature of the transducer mass to continue vibrating after the transducer has been fired. Ringing decays to acceptable levels in the order of milliseconds. Excessive cold or over tightening of the transducer mounting may increase the ring time such that it appears as an echo during the receive cycle. This is usually indicated by an incorrect high head reading. Excessive ring time may be overcome by increasing the blanking.

TEMPERATURE

The temperature as currently registered by the temperature sensor is viewed under D5. Data on the running minimum and maximum temperatures that have occurred since the last reset can be viewed in several ways:

F7 gives the running min/max temperatures and their time and date of occurrence since the last reset. F7 is reset by F8 but only after satisfying the security parameter F0.

D6/D7 give the respective running min/max temperature data, only, that have occurred since they were last reset. D6 is reset by entering a value lower than D5, and D7 is reset by entering a value larger than D5. D6 and D7 will then adopt the current temperature value and track the min/max values from that point on. The security parameter F0 does not need to be satisfied in order to reset D6 or D7.

Temperature data specific to the time and date can be viewed under the data log F14 (see \ Logging).

D14 indicates the resistance of the temperature sensor corresponding to the temperature shown in D5.

TIME AND DATE

If the data logging features of the OCM-3 are to be used, the time (F4) and date (F5) must be set. The day starts at 00:00:00 and ends at 23:59:59.

Adjusting the Time

If the clock time is advanced beyond the next anticipated logging time, the entry for each missed logging time is filled with a code which indicates that the system was not able to make entries at those times.

The daily total will be reduced proportional to the amount of time the day was shortened.

If the clock time is set back beyond the preceding logging time, the previously logged date will be written over with new data as the logging proceeds.

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 General Keypad Initial Start Up Fundamental Checks Start UPOperation Maintenance Error Codes 100 Communications 101 7ML19985AB01 AppendicesOCM Short About thisIf you want to know about Read Product OCM » 20 to 50 C -5 to 122 F Specifications» range 20 or 4-20 mA » resolution IP65 enclosureProgrammer » CE *, FM, CSA NRTL/CTransducer Temperature SensorCabling Auxiliary Input Communication SoftwareOutput » Belden Installing the OCM-3 InstallationOutline and Mounting OCM-3 Layout OCM-3 System DiagramCustomer device Ground shield at OCM-3 only Basic Wiring Temperature Sensor Installing the TransducerInstalling the Temperature Sensor Ground shield at OCM-3 onlyMA Output RelaysSynchronization AC Power Power ConnectionsDC Power Disconnect power before installing or replacing the battery Installing the Memory BACK-UP BatteryInstalling the Programmer Communicating VIA ComputerGeneral Start UPKeypad Language Initial Start UPOCM-3 is asking which language you prefer to communicate EnglishP0 language English P1 dimensional units Centimeters F13 auto zero calibration 160 Completed 7ML19985AB01114100 Enter new time 114124-hr. time F5 ddmmyyyy date October 12Fundamental Checks OCM Security OperationMemory UnitsAbsolute vs. ratiometric Flow CalculationDisplay = constantFor battery operation, set display lighting to off or auto Damping» 20 mA For battery operation, have relays energizing on alarmExample For relay » P6 * flow rate Flow Rate and Totalizing FAIL-SAFE Flow rate Logging CapacityViewing the data log Blanking TemperatureTime and Date Emulation Mode ResetVoltage Input Current Input Flow Velocity InputAuxiliary Head Input As normal 7ML19985AB01DC Output Diagnostic Aids100% head 4 m, enter 5 m Velocity Security access required‘D’ Parameter Listing Nominal target rangeOCM ‘F’ Parameter Listing Enter security code Emulation modeKeypad to mA output OCM Linear Velocity ‘P’ Parameter Listing= centimetres Gallons Flowrate Volume= absolute = ratiometric Flow rate units = 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 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 = gravitational acceleration = Ce x 2⁄3 ⎯⎯√2⎯g x be x he1.5 Where q = flow rate= approach width = Ce = crest width = K b = crest height = 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 A17 Head, point A18 Flow, point A13 Head, point A14Flow, point A15 Head, point A16 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 Universal Area X VELOCITY, P3 = Typical open channelArea Head Universal Area X VelocityA10 = OCM Maintenance Error Codes Computer Customer’sSerial printer Protocol for the OCM-3 is as follows Baud rate 102Bipolar Current DB-9 connectorDB-25 connector 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 00.000000 99.12399.123000 7ML19985AB01 Typical OCM-3Display value 107# = 0 through Content of P5 ResponseStop data log down load Start data log down load109 Cable DB-25 connector 7ML19985AB01Standard modem Computer Telephone lines Remote modemConnect Establishing Communication111 Ending Communication 112Rev
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