Siemens LU01 instruction manual Technical Reference, Transmit Pulse, Echo Processing

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Technical Reference

Transmit Pulse

The SITRANS LU01 transmit pulse consists of one or more electrical shot pulses, which are supplied to the scanning relay. The scanning relay is activated as required, to supply the transmit pulse to the Transducer(s) connected to the SITRANS LU01 terminals.

The transducer fires an acoustic shot for each electrical pulse supplied. After each shot is fired, sufficient time is provided for echo (shot reflection) reception, before the next (if applicable) shot is fired. After all shots of the transmit pulse are fired, the resultant echoes are processed.

The transmit pulse shot number, frequency, duration, delay, and associated measurement range are defined by parameters P803 and P840 to P852.

Echo Processing

Echo processing consists of echo enhancement, true echo selection, and selected echo verification.

Echo Enhancement is achieved by filtering (P821 and P822) and reforming (P823) the echo profile (digitized signal representing the echo signal received).

True echo selection is achieved by establishing the criteria which a portion of the echo profile must meet to be considered the true echo (echo reflected by the intended target).

Insignificant portions of the echo profile outside of the measurement range (Span P007 + Range Extension P801), below the TVT Curve (P830 to P835), and less than the Confidence Threshold (P804) and Short Shot Floor (P851) are automatically disregarded.

The remaining portions of the Echo Profile are evaluated using the Algorithm(s) (P820) and Short Shot Bias (P850) programmed. When a combination of Algorithms are used, the portion of the Echo Profile providing the best averaged Echo Confidence (P805), is selected as the true echo.

True echo verification is automatic. the position (relation in time after transmit) of the new echo is compared to that of the previously accepted echo. When the new echo is within the Echo Lock Window (P713), it is accepted and displays, outputs, and relays are updated as restricted by the Fuzz Filter (P710) and Rate Parameters (P700 to P703). If the new echo is outside of the Echo Lock Window, the new echo is not accepted until Echo Lock (P711) requirements are satisfied.

Technical Reference

7ML19985BE02

SITRANS LU01 – INSTRUCTION MANUAL

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Contents Sitrans Instrumentation described, variations Technical data subject to changeThis document is available in bound version Manual for agreement withTable of Contents Independent Relay Setpoints 100 Page Introduction IntroductionRS-232 or Local SmartLinxProgrammable Features Sitrans LU01 FeaturesUnits ManualInstallation category SpecificationsSpecifications Ambient temperatureOutputs ProgrammerRefer to associated product documentation TransducerOptions CableManual On Product Description Safety marking symbolsCable/Conduit Entry Requirements InstallationInstallation LocationTransducer Types Transducer MountingM 1.65 ft AC Model Communication Mode LEDSwitchterminal blockboard B RJ-11 port InterconnectionTB1 DC ModelLCD Card Optional SmartLinx ModuleBoard a Transducer System DiagramTo TS-3 Temperature SensorRelays MA OutputsSerial CommunicationSmartLinx Level System SynchronizationPosition. Select PowerAC Supply Wiring DC Supply WiringRJ-11 port RJ-11 cable Communications AccessProgrammer Use the hand programmer to change individual parametersDescription ProgrammingDisplay Display SegmentProgramming KeypadFunction keys Changing Parameters Program Mode EntryParameters Types Parameter Reset FeaturesProgramming Security Operation Display in RUN ModeOperation Ber Operation Key DescriptionP731 Operation Level Space or Distance Point Alarm Indicator RelaySystem Performance Evaluation Performance Test ResultsOperation Parameters Program modeParameter Reference Helpful HintsLated level P000 LockSecures the Sitrans LU01 from changes 1954 OFF programming permittedP003 Maximum Process Speed Quick Start P001 to P007P001 Operation P002 MaterialP004 Transducer Specifies measurement units used for dimensional valuesP005 Units P007 Span P006 EmptySets the range level to be measured P050 Tank Shape Application Parameters Volume P050 to P055Examples P051 Maximum VolumeDimension a as used in P050 Tank Shape P052 Tank Dimension aP053 Tank Dimension L Universal Volume CalculationEntering a Volume Breakpoint Typical volume calculationsEntering a Level Breakpoint P060 Decimal Position Display and Reading P060 to P062P061 Convert Reading Failsafe P070 to P072 P070 Failsafe TimerP062 Offset Reading Selecting HI, LO, or HOLd Material level reported when a Failsafe State is initiatedP071 Failsafe Material Level Once activated, the Failsafe State initiates the followingP072 Failsafe Level Advance Relays P100 to P119Relay reaction Option Relay # Point # Standard Alarm as % of Span, P007 P100 Preset ApplicationsP104 Low Low Alarm P101 High AlarmP102 Low Alarm P103 High High AlarmSets the control algorithm used to trip the relay Custom Relays P111 to P113P111 Relay Control Function FunctionValues For P111 Control Type Relay Control Independent Relay SetpointsRelays are energized and de-energized Action When P116 Dead Band Distance above and below the bound alarm setpointsP112 Relay on Setpoint P113 Relay OFF SetpointTo select an independent Relay Failsafe value Relay Function P111 Preset P129Independent Relay Failsafe P129 P129 Relay FailsafeP203 mA Output Value / Transducer MA Output P200 to P219P200 mA Output Range P201 mA Output FunctionP211 20 mA Output Setpoint Independent mA Setpoints P210 and P211MA Output Limits P212 and P213 P210 0/4 mA Output SetpointP215 20 mA Output Trim MA Output Trim P214 to P215P213 mA Output Max Limit P214 4 mA Output TrimStandard Data Logging P300 to P321 Record Temperatures P300 to P303P300 Temperature, Transducer Maximum MA Output Failsafe P219Code Description P302 Temperature, Sensor MaximumProfile Records P330 to P337 P330 Profile RecordP333 Auto Record Interval P331 Auto Record EnableAuto Record on and OFF Setpoints P334 to P337 P337 Auto Record LOE Time P334 Auto Record on SetpointP335 Auto Record OFF Setpoint P336 Auto Record Filling / EmptyingRange Calibration P650 to P654 Installation Records P340 to P342Offset Calibration Condition for use of this featureUsing Sound Velocity Calibration P651 Sound Velocity CalibrationP654 Velocity at 20C Value altered when an Offset Calibration is performedP652 Offset Correction P653 VelocityP660 Temp Source Temperature Compensation P660 to P664P664 Temperature View the transducer temperature in CP003 Value Meters/Minute Rate P700 to P707P700 Max Fill Rate P701 Max Empty RateP703 Emptying Indicator P702 Filling IndicatorP704 Rate Filter P707 Rate Value P705 Rate Update TimeP706 Rate Update Distance Measurement Verification P710 to P713P711 Echo Lock P711 value P712 preset valueP712 Echo Lock Sampling P726 Level System Sync P727 Scan DelayTransducer Scanning P725 to P729 P713 Echo Lock WindowP730 Auxiliary Reading P728 Shot DelayDisplay P730 to P733 P729 Scan TimeP731 Auxiliary Reading Key P732 Display DelayP733 Scroll Access Adjusts the Point Number display scroll speedP748 RS-485 Termination Peripheral Communication Support Parameters P740 to P749SmartLinx Reserved 750 to P740 Peripheral CommunicationsP772 Baud Rate SmartLinx Hardware TestingP790 Hardware Error Communications P772P794 SmartLinx Module Type P795 SmartLinx Protocol P791 Bus ErrorP792 Bus Error Count Echo Processing P800 to P807Determines what type of ultrasonic shots are fired P803 Shot / Pulse ModeP801 Range Extension P802 Transducer with Submergence ShieldDetermines which echoes are evaluated by software P804 Confidence ThresholdP805 Echo Confidence Display DescriptionAnatomy of an Echo Profile Advanced Echo Processing P810 to P825P806 Echo Strength P807 NoiseValues Display SymbolP810 Scope Displays ScrollingP818 Profile Pointer Distance Profile Pointer P817 to P825P816 Echo Time Raw P817 Profile Pointer TimeP820 Algorithm P819 Profile Pointer AmplitudeDampens spikes in the echo profile to reduce false readings P821 Spike FilterP822 Narrow Echo Filter P823 Reform EchoSelects the TVT Curve used Advanced TVT Adjustment P830 to P835P825 Echo Marker Trigger P830 TVT TypeTo change a breakpoint P832 TVT Shaper AdjustAllows manual adjustment of the TVT curve P831 TVT ShaperRange -30 to P833 TVT Start MinP834 TVT Start Duration P835 TVT Slope MinP841 Long Shot Number Advanced Shot Adjustment P840 to P852Adjust the short shot transmit pulse frequency in kHz P840 Short Shot NumberP850 Short Shot Bias P843 Long Shot FrequencyP844 Short Shot Width P845 Long Shot WidthP900 Software Revision Number Test P900 to P913P851 Short Shot Floor P852 Short Shot RangeP905 Transmit Pulse P902 WatchdogP903 Display P904 Keypad P910 Relay P912 Transducer Temperature P913 Sensor Temperature P907 Programmer InterfaceP922 Space Measurement Measurement P920 to P927P920 Reading Measurement P921 Material MeasurementP927 Distance Percent P924 Volume MeasurementMaster Reset P999 This feature resets all parameters to original valuesTechnical Reference Technical ReferenceTransmit Pulse Echo ProcessingDolphin Plus Display Distance CalculationSound Velocity Echo Processing Displays Scope Displays, P810Volume Level Volume CalculationUniversal, Linear P050 = Universal, Curved P050 = Maximum Process SpeedP003 Value Ment P728 Shot Delay s P803Application Examples ParameterMaterial Level Example 1 Level MeasurementNumber When satisfied with system performance and programmingInstructions Description Instructions Material VolumeP051 Max Volume Enter 1457 for 1457 m Example 2 Space MeasurementP001 P002 P003 P004 P005 P006 P007 P070 No entry required. preset for 20 mA = low level, P001 =P200 MA Range P213 MA Max Limit P219 MA Failsafe Technical Communication SupportApplication Assistance Reference NumberTechnical Reference Field Name MT-00 Measurement MessageDefinition Start of message Message type # # = rate alarm = band alarmMT-01 Hold Message Temp Percent End Of MessageSTX $02 MT-03 Point Not ScannedStart of message Message Type Point # End Of MessageMaintenance MaintenanceUnit Repair and Excluded Liability Symptom Cause Action Troubleshooting GuideTroubleshooting Flashing LOE Display To display Echo Confidence in the RUN modeTo update the value displayed after each aiming adjustment Measurement DifficultiesFixed Reading Wrong Reading Troubleshooting P000 Lock G Programming ChartsProgramming Charts NameP202 MA Allocation P203 P116 Bound Alarm Deadband P129 Relay FailsafeP330 Profile Record P331 Auto Record Enable G P332 P200 MA Range P201Programming Charts Parameter Advanced Echo Processing 7ml19985BE02