Siemens 7ML19985AB01 instruction manual Operation, Memory, Security, Units

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OPERATION

Upon power up, the transducer is fired periodically as set by P36. A long interval between measurements may be desirable in order to conserve power* when operating the OCM-3 from a DC source of limited capacity.

The echo is processed to determine the head (D0). The flow rate (D1) is calculated by the OCM-3 as a mathematical function (P3 and P4) of head or a function of head and velocity (P42). The flow rate is then integrated to yield the totalized flow (D2). The ‘Flow’ and ‘Total’ fields which are displayed during the normal running mode (F2) are also continuously updated.

Viewing or changing the content of a parameter (except F1, emulation) is done without disturbing the acquisition, processing or logging of flow data (see \ Security).

*restricted usage of display lighting (P14), relays (P15, 18 & 21), mA output and communications will also conserve power.

MEMORY

During a power interruption, the memory back up will hold the programming, the log and the totalizer values, and run the clock. The memory battery (B1) provides up to one year of memory retention (see Appendices \ Maintenance).

Note: To save parameter values, return to RUN mode (F2) after programming.

SECURITY

The content of all ‘A’, ‘D’, ‘F’, ‘P’ and ‘U’ parameters can be viewed without having to satisfy the security parameter, F0. However if it is desired to change the content of any of these parameters, the security parameter must be satisfied (except for resetting the running min/max displays, parameters D3/D4 and D6/D7).

Once security has been satisfied, access continues for 5 minutes after the last key is pressed or until F2 is re-entered.

The security code may be changed from its factory set value, 2.71828, by entering a new value into F10. It is imperative that the new value be recorded, as the code can not be viewed. If the code is lost, consult Milltronics.

UNITS

Programming of the OCM-3 involves setting the units of measure:

»P1 linear and velocity

»P2 temperature

»P5 flow rate and volume

If the units are changed during the course of operation, the change will be effected through all associated parameters and displays and will rescale flow and total data stored in the logs.

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 Start UP General Keypad Initial Start Up Fundamental ChecksOperation Appendices Maintenance Error Codes 100 Communications 101 7ML19985AB01OCM About this ShortIf you want to know about Read Product OCM IP65 enclosure Specifications» range 20 or 4-20 mA » resolution » 20 to 50 C -5 to 122 F» CE *, FM, CSA NRTL/C ProgrammerTemperature Sensor TransducerCabling Communication Software Auxiliary InputOutput » Belden Installation Installing the OCM-3Outline and Mounting OCM-3 Layout System Diagram OCM-3Customer device Ground shield at OCM-3 only Installing the TransducerInstalling the Temperature Sensor Ground shield at OCM-3 only Basic Wiring Temperature SensorRelays MA OutputSynchronization Power Connections AC PowerDC Power Communicating VIA Computer Installing the Memory BACK-UP BatteryInstalling the Programmer Disconnect power before installing or replacing the batteryStart UP GeneralKeypad English Initial Start UPOCM-3 is asking which language you prefer to communicate LanguageF13 auto zero calibration 160 Completed 7ML19985AB01 P0 language English P1 dimensional units CentimetersF5 ddmmyyyy date October 12 114124-hr. time 114100 Enter new timeFundamental Checks OCM Units OperationMemory Security= constant Flow CalculationDisplay Absolute vs. ratiometricDamping For battery operation, set display lighting to off or auto» P6 * flow rate For battery operation, have relays energizing on alarmExample For relay » 20 mAFAIL-SAFE Flow Rate and TotalizingFlow rate Capacity LoggingViewing the data log Temperature BlankingTime and Date Reset Emulation ModeAs normal 7ML19985AB01 Flow Velocity InputAuxiliary Head Input Voltage Input Current InputDiagnostic Aids DC Output100% head 4 m, enter 5 m Nominal target range Security access required‘D’ Parameter Listing VelocityOCM Enter security code Emulation mode ‘F’ Parameter ListingKeypad to mA output OCM ‘P’ Parameter Listing Linear Velocity= centimetres = imperial million gallons per day Flowrate Volume= absolute = ratiometric Flow rate units GallonsOCM = 4-20 mA = 0-20 mA 7ML19985AB01 OCM OCM Fixed Variable conditionUnits OCM ‘U’ Parameters for P3 Primary Element OCM U0 = exponent U1 = k factor P4 = 0 only Reference= 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 = crest width He = effective head h + Kh = head Kh = 1 mm = 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 accelerationBS-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 A19 Flow, point A13 Head, point A14Flow, point A15 Head, point A16 Flow, point A17 Head, point A18U0 = channel width B U1 = area h Rectangular Area X Velocity = head, cm = flow velocity, cm/sec Trapezoidal Area X Velocity = B b/d Where q = flow rate, l/s For h ≥ d= 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 =Universal Area X Velocity Area HeadA10 = OCM Maintenance Error Codes Customer’s ComputerSerial printer 102 Protocol for the OCM-3 is as follows Baud rateRefer to Cvcc Instruction DB-9 connectorDB-25 connector Bipolar CurrentDate P35 = 7, print interval set for 7 minutes104 Utilities Software Programmer Remote OCM-3 programming Remote OCM-3 display Local display105 106 107 Typical OCM-3Display value 00.000000 99.12399.123000 7ML19985AB01Response # = 0 through Content of P5Start data log down load Stop data log down load109 Computer Telephone lines Remote modem DB-25 connector 7ML19985AB01Standard modem CableEstablishing Communication Connect111 112 Ending CommunicationRev