A&D AD-4405 Adjustment of the Load Cell Output, Verifying Load Cell Output and Input Sensitivity

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A change in input voltage sensitivity is required to cause a one division change of the display. Select as large an input sensitivity voltage as possible so that the weighing interval becomes stable.

Consider the leverage if a lever is used.

3.1.3.Adjustment of the Load Cell Output

Caution

Use a metal film resistor in the range of 50kohm to 500kohm with a good temperature coefficient, when adding a resistor to adjust a load cell output. Use as large of a resistance value as possible in the range in which the zero adjustment is possible. Solder this resistor at a point near the load cell or the indicator.

In Case of Reducing the Output Voltage

When the zero output is too large, add a resistor between EXC+ and SIG-.

In Case of Adding an Offset Voltage to the Output When the zero output is too small, add a resistor between EXC+ and SIG+.

3.1.4.Verifying Load Cell Output and Input Sensitivity

The input sensitivity of the indicator is 0.25mV /division or more. Adapt to the following inequality, when you design a weighing instrument using the indicator and load cell(s).

Caution

						E * B * D
	Weighing instrument				0.25 £
	Weighing instrument
	using one load cell.					A
	using one load cell.					A

	Weighing instrument				0.25 £	E * B * D
	using multi-load cell				0.25 £	A * N
	using multi-load cell					A * N

A:Rated capacity of load cell [kg]

B:Rated output [mV/V]

D:Weighing interval [kg]

E:Excitation voltage [mV]

N:Number of load cells

Verification Example

	Design:
	Load cell	N=1		5000		* 3 * 0.05
	Rated capacity	A=750 [kg]		5000		* 3 * 0.05	= 1 ³ 0.25	. Therefore,

						750
	Rated output	B=3 [mV/V]				750
	Rated output	B=3 [mV/V]		regard the instrument as a good
	Excitation voltage	E=5000 [mV]		regard the instrument as a good
	Excitation voltage	E=5000 [mV]		design.
	Weighing interval	D=0.05 [kg]		design.
	Weighing interval	D=0.05 [kg]
	Weighing capacity	300 [kg]
3. Installation and Precautions		Page 6					AD-4405 Weighing Indicator

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Contents Weighing Indicator This manual and Marks Contents Setting the Parameters of Setpoint Comparison Compliance with European Directives ComplianceCompliance with FCC Rules Introduction Load Cell Connections Installation and PrecautionsInstallation and Precautions Adjustment of the Load Cell Output Verifying Load Cell Output and Input SensitivityInstalling an Option Board Description of Panels and symbols Front Panel DescriptionOther Displays and Symbols Rear Panel DescriptionAccessories and options Standard accessoriesSupplemental accessories for printer OptionsItems of Calibration Mode CalibrationCalibration Procedure Configuring a Weighing InstrumentSpecifying the Resolution, Decimal Point Position and Format Specifying the Range and UnitSpecifying the Second Range Resolution To Get Stabilized DataSpecifying the Weighing Range of the First Range Specifying the Second Range CapacityZero Calibration Span CalibrationExiting the Calibration Mode Weighing Range Function Setting the Division and Range Digital Linearization FunctionGravity Compensation Function Gravity Acceleration Table Calibration Error Code List Changing the Function Settings FunctionsFunctions OFFZERO+TARE = CAL EXT3 EXT1EXT2 Comparator Data Output Current Loop Output Serial Interface YY/MM/DD MM/DD/YY DD/MM/YYPrint Format CF-Functions Digital Input Preset Tare TareWeighing Tare Clearing TarePreparation and Specifications AccumulationDisplay and Operation Parameter Using Code Memory Code MemoryWeight Check Mode ComparisonLO, OK Condition formula for ComparisonHI, OK Mode Setting the Upper/Lower Limit ValuesSetting Order and Display for Weight Check Mode Setpoint Comparison Description of Input parameters and OutputsF22 = 7 Check weighing Output and ConditionF22 = 9 Check weighing 3Loss in weight Simple BatchStart Weighing CompletionReturns to Zero band Setting the Parameters of Setpoint ComparisonToward the Zero band Setting the Hold Functions Hold FunctionDisplay and the Data Output of Hold and Average Relations to the Other FunctionsKey input and command in the hold state Conditions of the Average and ReleaseTARE, ZERO, SETPOINT, Total MT, MZ, HCCounting Function Using the Counting FunctionUnit Weight Registration Key to register the unit weight and return to the piece YY/MM/DD Calendar / Clock13.1 Time and Date Functions Setting Time and Date Corrected date is as follows 05 05 Internal Printer OP-06 Installing the Printer Paper Special roll paper Replacing the Ink Ribbon15.1 Data Output / Print Mode Common Printer and Data Output ItemsData Number Interval Data Output / PrintSetting the Interval Time Interval Data Output / Print output16.1 Specifications RS-232C InterfaceCircuit and Pin Connection Bit FormatData Format FiguresCommand Format Explanation of CommandsCommands to Request Data Commands to Control the Indicator Changing the Weight Unit Changing the Code MemoryCommands to Set Parameters Set the Preset TareSet the Unit Weight for Counting Mode Set the Limit/Setpoint ValueCommands for the Hold Function Commands to Set the Data Output/ Print Format UFCStart Averaging to Hold Release the Hold DataUFC Commands UFC Command Parameters$DL SF1,$ID$DN$CR$LF$GR$UT$CR$LF’$AN$TL$LF$LF PF2,$DT$TM$LF$AN$SP$TL$LFRS-422/RS-485, Relay OutputOP-03 TRMCOM CircuitSwitching Between RS-422/RS-485 Circuits Relay Output & Control Input OP-05DC50V 19 -20mA Analog Output OP-07 SpecificationsSettings CL2 Current Loop Output OP-08CL1 Current Loop Output Data FormatSpecifications Analog Input and A/D ConversionDigital Section InterfaceDimensions GeneralMemo Memo Memo