Flow rate indication is not correct, 160 | Toshiba L5232 instruction

6F8A0917

13.2.2 Flow rate indication is not correct

START

Is the velocity range correctly set?

YES

Is zero point correctly set?

YES

NO

NO

Set it correctly according to 8. “Parameter Settings/Adjustment.”

Perform zero adjustment according to 6. “Operation” and 8.5 “Zero Adjustment.”

Is the exciting current correct?

YES

NO

Set the exciting current correctly according to 8. “Parameter Settings.”

Isn't the inside wall of detector pipe or electrode contaminated?

NO

Is the output load resistance 1k or less?

YES

Aren't there two load resistors connected to the output in parallel?

NO

Is accuracy calculated as follows?

(Measured flow rate) (Actual flow rate)

Actual flow rate

100 (%)

YES

Contact your nearest Toshiba representative.

YES

NO

YES

NO

Clean the inside wall of the detector pipe to remove the deposits.

Design the output circuit so that the output load resistance is less than 1 k.

Connect the two load resistors in series, if necessary.

Calculate as shown on the left.

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Image 161

Toshiba L5232 manual Flow rate indication is not correct, 160

Contents

6F8A0917 Electromagnetic Flowmeter Converter LF232 Type Nd Edition August First Edition June 6F8A0917 Color explanation Explanation of signal wordsSafety symbols Safety Precautions for Installation and Wiring Safety Precautions Usage limitation Safety Precautions for Maintenance and InspectionWarranty and Limitation of Liability Do not store or install the flowmeter Handling Precautions Handling Precautions Table of Contents 6F8A0917 6F8A0917 Storage Product Inspection and StorageProduct Inspection Overview Features Appearance Names of Parts Internal structure with converter cover opened Terminal block construction Hands Installation 6F8A0917 Unit inch mm How to Install the Converter Example of Pipe Mounting Urn off mains power before working on pipes WiringFrom mains power Do not conduct wiring work with bare hands Installation Cables Installation Cables External Connections 6F8A0917 Excitation cable Wiring MethodTerminal Treatment of Cables Terminal Treatment of Flow Rate Signal Cable Connecting the input signal cable Cable Connection Power cable, current output cable and digital I/O cables Connection to Terminal Block Grounding 9a Wiring between Detector and Converter 10 Detector Grounding Method Difficult 11 Connection Example of Electromagnetic Counter Digital I/O Connections Replacing the LF230 Converter InstallationWiring Combination with an Existing Detector for Large Meter Size 12 How to Connect an Adjusting Capacitor Replacement of partially filled pipes type 6F8A0917 Operation 6F8A0917 Display and Controls Display and Controls LCD display Operation switch infrared switchNames and Functions of Display and Controls Instructions Measurement mode Functions of each switchMenu display Setting mode Counter in operaiton Resets the counter Flow velocity value and instantaneous flow rate display Display FormatMeasured value display format Total difference flow value display Total count displayTotal flow value display Custom unit display Percent display Fixed output display Mode SwitchingError message / other message display ENTER111 6F8A0917 Moving to the menu display Setting Mode Operation To return from the menu display to the measurement mode Checking or changing the setting values Mode switching flow when password is set Password Input Example of password input mode selection SET and password Totalizer Operation Example of totalizer operation Example to move to the maintenance menu Maintenance Menu Return to measurement mode Setting Menu List Parameter Setting Items Parameter Settings / Adjustment Checking the exciting current value Parameters Check / ChangeExciting Current Value Changing the exciting current value Checking the meter size of the detector Meter Size Changing the meter size of the detector Checking the exciting frequency Exciting Frequency10,1/6,1/4 2.5 to 6 mm 26 to 120 500 to 3000 mm Changing the setting value for exciting frequency Checking the flow direction Flow Direction Changing the flow direction Switch Checking the password Password Setting Changing the password Checking the normal indicating unit Indicates the value in percent of the setting rangeNormal Indicating Unit Currently set main indicating unit % in this example Changing the flow direction for total flow Unit string of custom unit Custom UnitCoefficient of custom unit Proceed as follows to check the coefficient of custom unit Checking the coefficient of custom unitChanging the coefficient of custom unit Proceed as follows to check the unit string of custom unit Checking the unit string of custom unitChanging the unit string of custom unit Range type Span Value Range Unit of span Span value Hysteresis Span value range setting flowSetting sequence of span value range is shown below Range 2 span value Checking each constantRange 3 span value Range 4 span value Changing the range type Changing the span value Changing the hysteresis Proceed as follows to check the damping constant Damping ConstantChecking the damping constant Changing the damping constant Proceed as follows to check the low cutoff value Low Cutoff valueChecking the low cutoff value Changing the low cutoff value Checking the current output value used when an alarm occurs Current Output Setting Used When an Alarm OccursCurrent output setting function used when an alarm occurs Changing the current output value used when an alarm occurs Checking whether the display low cut is On or Off Display low cut On/Off Changing the display low cut On/Off setting Checking the output low limit value setting Output Low Limit SettingOutput low limit value Proceed as follows to check the output low limit value Changing the output low limit value setting Digital output functions corresponding to each terminal Digital output state only when alarm output is setDigital I/O Function Digital Input Function Digital Output alarm state Checking each setting for digital I/ODigital Input control signal level Digital Output Digital Output alarm status Changing each setting for digital I/O Count rate Pulse width modeCount Rate Pulse Rate and Pulse Width Over Spec Pulse width Pulse width Checking the count rate and pulse widthChanging the count rate Changing the pulse width mode setting Changing the pulse width Preset output function Preset CounterPreset count value Changing the preset count value Checking the preset counter setting 100 Changing the preset output function High/low limit alarm On/Off Flow Rate High/Low limit AlarmHigh/low limit value 101 High-high limit alarm Checking the high/low limit alarm settingLow-low limit alarm On/Off 102 103 Changing the high/low limit alarm On/Off 104 Changing the high/low limit value Setting the fluid empty alarm Fluid Empty AlarmChecking the fluid empty alarm On/Off setting 105 106 Changing the fluid empty alarm On/Off setting 107 Self-diagnosis function On/Off settingSelf-Diagnosis Function 108 Alarm output factor settingChecking the self-diagnosis alarm setting 109 Changing the self-diagnosis function setting Rate-of-Change Limit Value and Control Time Checking the rate-of-change limit settingRate-of-change limit value Rate-of-change control time 111 Changing the rate-of-change limit setting 112 Initial Settings When Shipped from the Factory 113 Fixed output mode can be selected by the setting as follows Fixed value output On/Off settingFixed Value Output Loop Check Fixed current output value 115 Checking the fixed output function settingFixed pulse output value 116 Changing the fixed output function 117 Changing the fixed output constant 118 Zero AdjustmentStill Water Zero Adjustment 119 How to calculate the zero offset value Zero Offset AdjustmentChecking the zero offset adjustment value 120 121 Changing the zero offset adjustment value 122 Mag-Prover CalibrationCalibration Items 1 0% Flow Rate Calibration Zero Calibration Converter Check / CalibrationChecking the zero point Calibrating the zero point Checking the 50% flow rate value 2 50% Flow Rate Calibration124 50% flow rate value can be checked only Checking the span value 3 100% Flow Rate Calibration Span CalibrationCalibrating the span value 125 Monitor value of the exciting current can be checked Checking the Exciting Current Value126 127 Function Description Digital Outputs Digital I/O SpecificationsDigital Input option 128 129 Totalizer and Pulse Output 130 131 Totalizer operation using digital input signals 132 Multi-Range Functions 133 Output performance when multiple ranges are usedSingle direction internal automatic switching, 4 ranges Forward direction Direction Output when switched from Reverse to134 135 Single direction external signal switching, 2 ranges 136 137 Single direction external signal switching, 4 ranges Flow rate high/low limit alarm output performance Flow Rate High/Low Limit Alarm Output138 Case of Single range 139 Case of Multi-range setting 140 Output when an alarm is generated Fluid Empty Alarm OutputAlarm output state described in 8.2.14 Digital I/O Function 141 142 Preset Counter Output Function 143 Preset counter output performance 144 Output example of one-shot pulse output 145 146 Remote Still Water Zero Adjustment 147 Remote Selection of Fixed Value Output 148 Converter Error Alarm Output 149 Communications FunctionConnection with the HHT terminal Connection to the Converter Main Unit 150 151 Procedure for Communication with HHT Interference on 4 to 20mA current signal Wiring cableUse a shielded cable CVV-S, etc for wiring Current output load Diagnostic messages Diagnosis and AlarmsSetting error High/low limit alarm 154 Process error alarmFluid empty alarm 155 Self-diagnosis error 156 Output When an Error or Alarm Occurs Maintenance Maintenance and Inspection Product disposal Check / Replacement of power supply unitOperative life 158 159 TroubleshootingFlow rate is not indicated 160 Flow rate indication is not correct 161 Flow rate indication is not stable 162 When switch operation is unable = K × B × D × Q Principle of Operation163 Specifications SpecificationsDetector Combined Specifications 164 165 166 Converter specifications 167 168 169 Model Number Table 170 171 Outline DrawingElectromagnetic Flowmeter Converter LF232 Type Gross mass approx lb8kg including a mounting plate 172 FCF50017