D4 Instruction Manual - strain gages

Model D4 Data Acquisition Conditioner Instruction Manual Version 1.34

Micro-Measurements P.O. Box 27777 Raleigh, NC 27611 USA Phone: (919) 365-3800 Email: [email protected] Website: www.micro-measurements.com January 2013

130-000208

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Model D4 Data Acquisition Conditioner Instruction Manual

TABLE OF CONTENTS 1 DESCRIPTION ....................................................................... 1 1.1 General .......................................................................... 1 1.2 Functional Features ...................................................... 2 2 SPECIFICATIONS ................................................................. 3 2.1 Input Connections ......................................................... 3 2.2 Bridge Configurations ................................................... 3 2.3 Data Conversion ............................................................ 3 2.4 Measurement Range/Resolution .................................. 4 2.5 Measurement Accuracy ................................................ 4 2.6 Gage Factor Control ...................................................... 4 2.7 Balance Control ............................................................. 4 2.8 Bridge Excitation ........................................................... 4 2.9 Communication Interface ............................................. 4 2.10 Shunt Calibration .......................................................... 5 2.11 Power ............................................................................ 5 2.12 Operational Environment ............................................. 5 2.13 Case ............................................................................... 5 2.14 Size and Weight ............................................................ 5 3 FRONT AND REAR PANELS .............................................. 6 3.1 USB Interface ................................................................ 7 3.2 Input Connectors .......................................................... 7 3.3 Status LED ..................................................................... 7 3.4 Software ........................................................................ 7 4 HARDWARE OPERATION ................................................. 8 4.1 Power Up....................................................................... 8 4.2 Input Connections ......................................................... 8 4.2.1 4.2.2

Pin Functions ......................................................................... 8 Strain Gage and Transducer Input Circuits ......................... 11

5 SOFTWARE OPERATION ................................................14 5.1 Overview ..................................................................... 14

Model D4 Data Acquisition Conditioner Instruction Manual 5.2 5.3 5.5 5.6 5.7

Connecting the D4(s) to the PC ................................... 14 Application Startup ..................................................... 15 Screen Management ................................................... 16 Control Screen............................................................. 16 Monitor Screen ........................................................... 16 5.7.1 5.7.2

5.8

Identify a D4 ........................................................................ 17 Peak Values ......................................................................... 17

Channel Configuration ................................................ 19 5.8.1 5.8.2 5.8.3 5.8.4 5.8.5

5.9 5.10

Saving and Recalling Settings (PC) .............................. 26 Saving Settings to the D4 ............................................ 27

5.10.1 5.10.2 5.10.3 5.10.4

5.11

Charting Controls ................................................................ 29 Charting Colors .................................................................... 30

Recording .................................................................... 30

5.12.1 5.12.2

5.13

Reset (Set to Default) .......................................................... 27 Excitation Output and Noise Rejection Settings ................. 27 Format Offscale Value ......................................................... 28 Poisson’s Ratio .................................................................... 28

Charting ....................................................................... 29

5.11.1 5.11.2

5.12

Channel Name ..................................................................... 20 Bridge Type ......................................................................... 20 Number of Decimal Places to Display ................................. 23 Scaling ................................................................................. 23 Balance (Zero) ..................................................................... 24

Setting up the Data File ....................................................... 30 Data File Format .................................................................. 31

Calibration ................................................................... 33

5.13.1 5.13.2 5.13.3

Shunt Calibration ................................................................ 33 System Calibration Software ............................................... 34 Required Instruments ......................................................... 34

5.14 Program Messages ...................................................... 40 5.15 Upgrading Firmware ................................................... 40 6 WARRANTY ........................................................................ 42


Model D4 Data Acquisition Conditioner


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1 DESCRIPTION 1.1

General

The Model D4 Data Acquisition Conditioner is a portable, USB-powered, precision instrument for use with resistive strain gages and strain gage–based transducers. The Model D4 has four channels of data acquisition. Connection to each channel is via an RJ-45 connector. Each channel of input accepts full-, half-, or quarter-bridge configuration. All required bridge completion components for 120-, 350-, and 1000-ohm bridges are supplied. Operation of the Model D4 is performed with commands sent via the USB connection. Application software is provided to control the D4 with an MS Windows–based personal computer. A programmer’s reference kit is available to simplify writing custom applications. The Model D4 uses modern digital signal processing technology to provide excellent noise rejection and stability. Proprietary scaling and linearization algorithms provide unsurpassed measurement accuracy for strain-gage bridge measurements.

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1.2

Functional Features

The Model D4 Data Acquisition Conditioner has the following features:  Four input channels.  Hardware and software support for quarter-, halfand full-bridge circuits.  Built-in precision bridge completion for 120-, 350and 1000-ohm half and quarter bridges.  8Hz sampling rate.  Automatic and manual zero-balance and calibration.  Full control of all functions via the USB Interface.  Portable, lightweight, rugged design.  Powered via the USB interface.  Intuitive, user-friendly software.  Programmability.

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2 SPECIFICATIONS  Note: Performance may be degraded at high levels of repetitive electrostatic discharge; however, no damage to the unit will occur.

2.1

Input Connections

Type: RJ-45 Modular Quantity: Four

2.2

Bridge Configurations

Types: Quarter, half, and full bridges Bridge Impedance: 60Ω to 2000Ω Internal Bridge Completion: Quarter bridge: 120Ω, 350Ω, and 1000Ω ±0.01% Half bridge: 1000Ω ±0.01%

2.3

Data Conversion

A/D Converter: Delta-sigma with integral chopper-stabilized, programmable gain instrumentation amplifier. Resolution: 24 bits. Noise-free resolution: 18 bits typ. Filter: Integrated linear phase FIR Sinc5 filter followed by a Sinc3 filter with a programmable decimation rate. Software selectable output rate provides >120 dB rejection of 50Hz, 60Hz and higher level harmonics.

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2.4

Measurement Range/Resolution

Strain Range: ±31,000με at GF = 2.000. (±15.5 mV/V) Resolution: ±1με at GF = 2.000 (±0.0005 mV/V)

2.5

Measurement Accuracy

±0.1% of reading ±3 counts. (Instrument Gage Factor = 2.000)

2.6

Gage Factor Control

Range: 0.500 to 9.900

2.7

Balance Control

Type: Software Control: Manual or automatic

2.8

Bridge Excitation

Value: 1.5 VDC nominal Control: Software enable/disable Measurements are fully ratiometric and not degraded by variations in excitation voltage.

2.9

Communication Interface

Universal Serial Bus (USB). Cable included.

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2.10 Shunt Calibration Location: Across each quarter-bridge completion resistor Control: Software Values: P- to D120: 11.94KΩ ±0.1% (5000με at GF = 2.00) P- to D350: 34.8KΩ ±0.1% (5000με at GF = 2.00) P- to D1000: 99.5KΩ ±0.1% (5000με at GF = 2.00)

2.11 Power USB: 5V 100mA

2.12 Operational Environment Temperature: 0° to +50°C Humidity: Up to 90% RH. Non-condensing.

2.13 Case Material: Aluminum

2.14 Size and Weight Size: 4.3W x 1.4H x 5.7L inches (110 x 36 x 145 mm) Weight: 0.8 lb. (0.36 kg)

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3 FRONT AND REAR PANELS Status LED

USB Port

Input Connectors

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3.1

USB Interface

The USB interface is the communication channel between the Model D4 and a host PC. When connected, a PC (running MS Windows XP, Vista, or 7) identifies the D4 as a standard USB Human Interface Device; therefore, no special device drivers are required.

3.2

Input Connectors

The input connectors connect the strain gage or transducer to the D4. Mating connectors for the D4: Tyco 554739 or equivalent (MM Part No. D4-A106) Recommended crimping tool for the mating connectors: Tyco 3-231652-0 (MM Part No. D4-A108) Note: Crimping tool can be used on both shielded and unshielded connectors.

3.3

Status LED

The Status LED illuminates when the D4 is powered up and ready for operation.

3.4

Software

The D4 is shipped with user-friendly application software that provides data recording and control as well as calibration. A Programmer’s Reference Kit is included that contains a Programmer’s Reference Manual, an NI LabVIEW instrument driver, and programming examples.

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4 HARDWARE OPERATION 4.1

Power Up

The D4 receives its power via the USB connection. The Status LED illuminates when the D4 is ready to begin operation.

4.2

Input Connections

Strain gages and strain gage–based transducers are connected to the D4 through the four input connectors labeled 1 through 4. 4.2.1 Pin Functions Each channel of the D4 accommodates an eight-pin modular plug (MM Part No. D4-A106). The pin arrangement and functions are shown in Table 1 and in Figure 1. Input Shielding: To reduce noise and protect the integrity of the bridge signal from electrostatic discharge (ESD) and radio frequency (RF) noise, a shielded cable connection is recommended. The shield or drain wire should be connected to the shield of the input connector. Symbol PP+ SD120 D350 S+ D1000 N/C SHIELD

Strain Gage Card Function Negative Excitation Positive Excitation Negative signal amplifier input 120 ohm Dummy Resistor 350 ohm Dummy Resistor Positive signal amplifier input 1000 ohm Dummy Resistor Unused Shield

Pin 1 2 3 4 5 6 7 8 S (Shield)

Table 1 - Model D4 Individual Pin Functions

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Figure 1 - Model D4 Input Plug Orientation

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EXCITATION +

2

SIGNAL +

6

EXCITATION –

1

SIGNAL -

3

D120

4

D350

5

D1000

7

SHIELD

S

Connector on D4

Figure 2 - Model D4 Input Plug Connections

Half-Bridge and Quarter-Bridge Inputs: In addition to fullbridge operation, the D4 can accept half- and quarter-bridge configurations. Internal completion resistors are provided for 120Ω, 350Ω, and 1000Ω quarter-bridges. A 1000Ω internal half-bridge circuit is available for quarter- and half-bridge configurations. The connection to S+ for the half-bridge completion resistors is under firmware control. - 10 -


4.2.2 Strain Gage and Transducer Input Circuits The basic input circuits for strain gage and strain gage–based transducers are shown in Figure 3 through 9.

EXCITATION + 2

D120

4

SIGNAL -

3

SHIELD

S

Figure 3 – 120 Ohm Quarter Bridge / Three-Wire Connection

EXCITATION + 2

D350

5

SIGNAL -

3

SHIELD

S


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EXCITATION + 2

D1000

7

SIGNAL -

3

SHIELD

S


EXCITATION + 2

SIGNAL -

3

EXCITATION -

1 REXT S

SHIELD

Figure 6 – Quarter Bridge / External Dummy

EXCITATION + 2

SIGNAL -

3

EXCITATION -

1

SHIELD

S

Figure 7 – Half Bridge / Adjacent Gages

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EXCITATION + 2

SIGNAL -

3

EXCITATION -

1

SHIELD

S

Figure 8 – Half Bridge / Separate Gages

EXCITATION +

2

SIGNAL +

6

EXCITATION -

1

SIGNAL -

3

SHIELD

S

i

Figure 9 – Full Bridge / Four-Wire plus shield

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5 SOFTWARE OPERATION 5.1

Overview

The Model D4 is supplied with application software to configure the D4 and collect data via the USB Interface. The software supports a combination of up to six Model D4 or Model P3 devices, differentiated by serial number. The firmware version of your D4 (or P3) must be 2.50 or greater to work with this application. Use the upgrade firmware feature of your previous application to update the firmware to the latest level.

5.2

Connecting the D4(s) to the PC

Connect the USB interface on the D4 to an open USB port on the PC using the supplied cable. After the Status LED on the D4 illuminates, the PC should recognize the D4 automatically. When multiple D4s or P3s are connected at the same time, it may take the PC several minutes to recognize all units. You may monitor the PC’s recognition of each device in the Windows Device Manager. A USB Human Interface Device will appear in the Device Manager for each D4 and P3 connected.

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5.3

Application Startup

Once the devices are connected to your PC, start the application from Windows by navigating to the following item in the startup menu: Start>>Programs>> Micro-Measurements P3-D4>> P3-D4 Application The application will automatically connect to the devices. Depending on the speed of the PC and the number of devices, this process can take 1-5 minutes. When the software has recognized the devices, the software will display a Monitor Screen for each device connected and one Control Screen that contains the menu bar.

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Model D4 Data Acquisition Conditioner Instruction Manual Note: Additional devices should not be added while the application software is running. Exit the software before adding or removing devices from the system.

5.5

Screen Management

The Control Screen and Monitor Screens may be moved by clicking and dragging the title bar. A Monitor Screen may be re-sized by clicking and dragging the lower right corner of the screen.

5.6

Control Screen

The control screen gives you access to the main program menu and the recording controls.

5.7

Monitor Screen

The Monitor Screen shows the channel readings. By default, the channel readings are active when you start the program. To turn the readings display on or off, on the Control Screen menu, select Hardware>>Real Time Display.

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Model D4 Data Acquisition Conditioner Instruction Manual The screen on the left shows a Monitor Screen when readings are inactive. The screen on the right shows the screen when readings are active. Note that readings are grayed out when the display is inactive.

5.7.1 Identify a D4 The serial number of each D4 displays in the title bar of the window. If you need to identify which D4 is associated with a serial number, you may select Hardware>>Identify and then select that serial number. The LED light will blink on the D4 that has that serial number. 5.7.2 Peak Values The display of peak values (“Min peak” and “Max peak”) may be turned on or off with the menu item File>>Display Peak Values. Peak values for all channels may be reset with the - 17 -

Model D4 Data Acquisition Conditioner Instruction Manual menu item Channels>>Reset Peak Values. Peak values for a specific channel may be reset by right-clicking in the channel reading segment and selecting Reset Peak.

No peak values displayed

Peak values displayed

Peak values reset

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5.8

Channel Configuration

To access the configuration values for a channel, select Channels>>Settings on the Control Screen. (The real-time display readings must be disabled to access this screen.) If multiple devices are connected, click on the serial number of the desired D4 under Devices. The LED light on that D4 will blink to confirm the selection. Click on the channel to be configured. Note: Each of the four channels on a D4 must be set independently.

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Model D4 Data Acquisition Conditioner Instruction Manual At the bottom of the screen are three buttons:  Click Cancel to exit the screen without saving changes. Note: Cancel will not undo any changes that have been applied.  Click Apply to apply the configuration changes immediately. Results may be viewed on the Monitor Screen.  Click OK to exit the channel configuration screen and save changes. 5.8.1 Channel Name The channel name entered will identify the channel on the Monitor Screen and in the recorded data file. The default is: Channel N, where N is the channel number 1 through 4. 5.8.2 Bridge Type The bridge type determines whether the internal half bridge is used and determines the appropriate scaling/linearization algorithm. The following table summarizes the bridge types. For more information on the calculations used by the D4, please contact the Micro-Measurements application engineering department. The following bridge configuration examples assume that the raw strain data is to be reduced to equivalent uniaxial strain with the nonlinearity correction applied where appropriate. Select the "Undef" bridge, either Half-Bridge/Quarter-Bridge or Full-Bridge when you require the net output of the active strain gages without mathematical correction for either bridge.

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Model D4 Data Acquisition Conditioner Instruction Manual Selection

Bridge Diagram

Description

Quarter

Single active gage in uniaxial tension or compression.

HB adj ,-

Two active gages with equal and opposite strains—typical of bending-beam arrangement.

HB opp ,-

Two active gages with equal strains of the same sign—used on opposite sides of column with low thermal gradient (bending cancellation, for instance.)

HB shear

Two active gages with equal and opposite strains aligned with the maximum and minimum principal strains to measure shear strain.

HB adj ,

Two active gages in uniaxial stress field— one aligned with maximum principal strain, the other with transverse "Poisson" strain. Default Poisson’s Ratio = 0.3.

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Bridge Diagram

Description

FB 4 active

Four active gages with pairs subjected to equal and opposite strains (beam in bending).

FB shear

Four active gages with pairs subjected to equal and opposite strains (shaft in torsion). Four active gages in uniaxial stress field— two aligned with maximum principal strain, the other two with transverse "Poisson" strain (column). Default Poisson’s Ratio = 0.3. Four active gages in uniaxial stress field— two aligned with maximum principal strain, the other two with transverse "Poisson" strain (beam). Default Poisson’s Ratio = 0.3.

FB  opp

FB  adj

Undefined full bridge circuit. No correction for Wheatstone Bridge nonlinearity or active arms.

Undef FB

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Bridge Diagram

Description Undefined half- or quarter-bridge circuit. No correction for Wheatstone Bridge nonlinearity or active arms.

Undef HB/QB

Table 2 Bridge Types

5.8.3 Number of Decimal Places to Display Enter the number of values you would like to have after the decimal place on the displayed data. Value 0 1 2 n

Description Display no decimal places; e.g. 123 Display 1 decimal place; e.g. 123.1 Display 2 decimal places; e.g. 123.12 Where n is the number of decimal places.

5.8.4 Scaling The engineering units for a channel may be microstrain (ue), millivolts per volt (mV/V), or may be user defined. Scaling options on the D4 are determined by the units selected. 5.8.4.1 Strain Gage Inputs Microstrain: If the selected units are ue (microstrain), scaling is determined by the gage factor of the sensor as follows: Range: 0.500 to 9.900 Default: 2.000 Millivolts per volt: If the selected units are millivolts per volt (mV/V), no scaling is necessary.

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Model D4 Data Acquisition Conditioner Instruction Manual 5.8.4.2 Transducer Inputs Custom: User-defined units (such as psi or cm) assume linear scaling. To properly scale the data, enter the following parameters:  Engineering Units Enter up to four characters. This will be displayed in the channel segment on the Monitor Screen. 

Full Scale in mV/V Enter the millivolt per volt value at full scale. This value is used in conjunction with the Full Scale in Engineering Units value. It is used with engineering units other than microstrain (ue) or mV/V. During manual shunt calibration, fix the full-scale value in engineering units and change the full-scale mV/V value. It is recommended to set this value at or near the expected full-scale value when manually scaling the channel. Range: -15.625 to +15.625 (excluding 0) Default: 2.000



Full Scale in Engineering Units Defines the full-scale value for engineering units other than ue or mV/V. All scaling is linear. Range: -99999 to 99999 (excluding a value of 0) Default: 1

5.8.5 Balance (Zero) Balancing specifies that the current value of a sensor is the zero offset reading. Because this zero offset reading is rarely 0.00, it is typically subtracted from all subsequent readings. Channel readings returned from the D4 have the zero offset removed. - 24 -


You may auto-balance a channel, manually balance the channel, or disable the removal of the zero offset. The default balance value is 0. 5.8.5.1 Auto Balance (Zero) The steps in performing an auto-balance operation for a single channel are: 1. Enter all of the other channel settings before you auto balance. 2. Adjust the sensor to the correct setting for a zero reading. 3. Set the Balance Mode of the channel to Auto. 4. Click the Zero button. 5. The new balance value is reflected in the slide bar and applied to the channel reading. A zero (auto-balance) also may be applied to an individual channel on the Monitor Screen by right-clicking in the channel segment and selecting Zero. You may also perform a zero (auto-balance) of all channels on all D4s by the menu item Channels>>Zero All. 5.8.5.2 Manual Balance Before performing a manual balance operation, it is recommended that the real time display is active. The steps in fine-tuning the balance value after an auto-balance operation are: 1. Perform the auto-balance operation; make sure the value is applied. (If you don’t wish to auto-balance first, then configure the channel and adjust your sensor to the correct setting for a zero reading.) - 25 -

Model D4 Data Acquisition Conditioner Instruction Manual 2. Set the Balance Mode to Manual. 3. The balance value from the auto-balance operation is reflected in the slide bar. The balance value is displayed in raw counts. 4. Depending on the current reading and the desired reading, adjust the balance value on the slide bar either up or down. The slide bar has the range selections of coarse, medium, fine and ultra-fine. The coarse selection has the widest range of balance settings and a coarser step size. Ultra-fine has the narrowest range of balance settings and a small step size. The medium and fine selections fall in between. 5.8.5.3 Balance Mode Disabled Channels with the Balance Mode disabled will not remove any zero offset from the reading; however, the initial amplifier zero is removed. This mode allows you to evaluate initial bridge offsets. Click the Apply button to see the changes reflected in the channel reading on the Monitor Screen.

5.9

Saving and Recalling Settings (PC)

You may save the application’s current settings to a file on your PC with the menu item File>>Save Configuration. The settings may be recalled with the menu item File>>Load Configuration. In addition to the channel settings, the Poisson’s Ratio, Record Interval, Peak Value setting and Offscale Values are saved.

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5.10 Saving Settings to the D4 The menu item Hardware>>Save Configuration to Flash lets you select a device and store the current device settings to the device’s internal flash memory. This will become the default configuration for the device after a power-cycle. If you wish to return the factory default settings, use the Channels>>Reset All menu item to reset the settings and then store those settings to flash. Channel Readings Adjustments 5.10.1 Reset (Set to Default) The menu item Channels>>Reset All resets the channel configuration values on all devices to their default settings. 5.10.2 Excitation Output and Noise Rejection Settings The Hardware>>Other Device Settings menu item allows you to access the Excitation Output setting and the Noise Rejection frequency setting. These fields are only available if the D4 firmware level is 2.42 or greater. The bridge excitation output should be enabled during normal operation. You may disable the excitation output to identify self-generating noise sources. The digital filters in the D4 may be tuned to optimize the noise rejection from power line frequencies.

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Model D4 Data Acquisition Conditioner Instruction Manual 5.10.3 Format Offscale Value You may specify the value that is used to indicate positive offscale and negative offscale readings using the menu item File>>Configure Offscale Display. This value is used on the Monitor Screen and in recorded data. If you are planning on charting your recorded data with a spreadsheet, you may wish to change these values to a numeric (for example, 99999 and -99999). 5.10.4 Poisson’s Ratio You may define the Poisson’s ratio of the material to which the strain gage is bonded using the menu item Hardware>>Poisson’s Ratio. Poisson’s ratio is used to calculate strain in bridge configurations that are dependent upon Poisson’s ratio. This value is shared among all channels on the selected D4. Range: 0.0 to 0.5 Default: 0.3

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5.11 Charting Charting maps the real time display readings. To begin charting, select Channels>>Chart. The chart window will display and charting will begin.

5.11.1 Charting Controls The following fields displayed at the bottom of the screen may be used to control the charting:  Pause Display checkbox – Suspends/resumes the charting.  Update Interval – Enter the desired interval for how often the chart is updated in milliseconds. The minimum interval is 125 milliseconds.  Number of points – Enter the desired number of data points (readings) to be displayed.

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Model D4 Data Acquisition Conditioner Instruction Manual 

 

Min Y Axis – Two options exist for charting the minimum Y axis value: o One is to check the Auto (min) box. This will automatically adjust the min value based on the min value of the plotted data. o Or, uncheck the Auto checkbox. This will allow entry of a fixed value in Min Y Axis. Max Y Axis – As with the minimum value, either check the Auto checkbox, or uncheck it and enter a value in Max Y Axis. Channels - Select the channels to be charted.

5.11.2 Charting Colors Colors may be adjusted by selecting File>>Configure Chart Trace Colors. Select and save the colors prior to launching the chart.

5.12 Recording The D4 application software supports both manual and timebased recording. 5.12.1 Setting up the Data File To specify the data file name and location, click Select File on the Control Screen. Browse to the path of the desired location, enter the file name, then click Save.

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Model D4 Data Acquisition Conditioner Instruction Manual 5.12.1.1 Time-based Recording The application records data on a periodic basis. To set the interval, select File>>Record Interval. The minimum recording interval for a scan is 125 milliseconds. A scan is defined as one reading from all active channels. Active channels are displayed on the Monitor Screen(s). Note: P3s cannot acquire data faster than 2Hz. Time-based recording can be started, paused, or stopped from the Control Screen. 5.12.1.2 Manual Recording Click the manual recording button Manual Record (Single Shot) to record one scan to the data file. Manual recording can be performed when time-based recording is active. The maximum recording rate is 8Hz. 5.12.2 Data File Format The data is stored in a standard, ASCII-format text file. This format may be viewed with MS Notepad or with a spreadsheet program such as MS Excel. The first line is the data header. All columns are separated by the ASCII tab character 09 (09h). The line is terminated with a carriage return and line feed. Subsequent lines contain the tab-delimited data. All lines are terminated with a carriage return (ASCII character 13 (0Dh) and line feed (ASCII character 10 (0Ah).

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Text file shown in Notepad

File shown after import into MS Excel

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5.13 Calibration 5.13.1 Shunt Calibration Shunt Calibration functionality allows you to adjust the sensitivity of the selected channel (gage factor or full-scale value) while a calibration signal is applied. The shunt calibration factor is primarily used to remove any offsets due to lead-wire resistance. When you enable shunt calibration, a precision shunt resistor is placed between the P- and the appropriate dummy (D120, D350, D1000) resistor. The internal shunt calibration resistors simulate an equivalent strain of 5000με at a gage factor of 2.000. The shunt resistor is applied to all channels simultaneously. The steps in performing a shunt calibration are: 1. Configure the channel. 2. Balance (zero) the channel. 3. Enable the shunt calibration by selecting Hardware>>Enable Shunt Calibration on the Control Screen. 4. View the adjusted channel reading on the Monitor Screen. 5. If the channel’s engineering unit is set to ue (microstrain), adjust the gage factor. If the engineering units are user-defined, adjust the fullscale in millivolts/volt setting. Click the Apply button to see the changes reflected in the channel reading on the main screen. 6. Loop through steps 4 and 5 until the desired reading is obtained. 7. Unselect Hardware>>Enable Shunt Calibration on the Control Screen. - 33 -

Model D4 Data Acquisition Conditioner Instruction Manual 5.13.2 System Calibration Software To calibrate a D4, first stop the channel readings by unselecting Hardware>>Real Time Display on the Control Screen. Then select Hardware>>Calibrate on the Control Screen and select the serial number of the D4 to be calibrated. Note: Performing an improper calibration may render your D4 inoperable. 5.13.3 Required Instruments The calibration process requires a Micro-Measurements Model 1550A Strain Indicator Calibrator, or another device with equivalent features and specifications. The D4 is a ratiometric measuring device, so measurement is not affected by fluctuations in the excitation voltage. It is therefore important to use a Wheatstone Bridge–based calibrator. Other sources, such as a precision voltage reference, are not suitable for calibration purposes. This section assumes that you are using a Model 1550A. The system calibration process takes four measurements on each channel: zero, positive and negative full scale, and amp zero. After the measurements are taken, calibration values for amplifier zero and software gain are stored in the internal flash memory. Following are the steps involved in performing a system calibration. These steps must be performed in the order shown and all channels must be calibrated. To abort the process after beginning calibration, select the Abort Calibration button and power-cycle the D4. To abort before beginning calibration, select Exit Calibration.

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Model D4 Data Acquisition Conditioner Instruction Manual Note: Each time Take Reading is selected, in-process and completion messages are displayed in the status bar at the bottom left of the screen. Step 1: Get previous calibration values (optional) Before calibrating the system, you may want to report the last calibration date and the previous (on-card) calibration settings for each channel. Select the Get Previous Cal Values button to retrieve the data from the D4. Enter any desired text into the Additional Report Data text box; this text will be included in saved/printed calibration reports.

To save and print a calibration report, select the Save Previous Cal Values button. When the Save As window displays. navigate to the desired location in which to save the file. Retain the default file name or change as desired. The default file name for the calibration report, whether created before or after calibration, is as follows: SSSSSS_YYYY_MM_DD_M-M_Device_Cal_Report.txt where: SSSSSS is the serial number of the D4, YYYY_MM_DD is the date, and M-M_Device_Cal_Report.txt is the terminator.

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Model D4 Data Acquisition Conditioner Instruction Manual When Save is clicked, your default text file viewer, e.g., MS Notepad, will be launched, displaying the calibration values. The file may be printed using the viewer.

Step 2: Calibrate each channel All of step 2 must be repeated for each of the four channels on the D4. The channels may be calibrated in any order, but steps 2A through 2E must be performed sequentially. Begin by selecting a channel (1 through 4) from the drop-down list.

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Model D4 Data Acquisition Conditioner Instruction Manual Step 2A: Install calibrator on selected channel Configure the Model 1550A Strain Indicator Calibrator as a full-bridge circuit and install on the selected channel. See Figure 9 for connection details. Step 2B: Take a zero reading Set the 1550A calibrator to 0 µε, positive polarity and click the Take Zero Reading button. Step 2C: Take a positive, full-scale reading Set the 1550A calibrator to +30,000 µε (positive polarity) and click the Take Reading button. Step 2D: Take a negative, full-scale reading Set the 1550A calibrator to -30,000 µε (negative polarity) and the click the Take Reading button. Step 2E: Take an amp zero reading Finally, the system needs to establish a true electrical zero (amp zero). Set the 1550A calibrator to 0 µε, positive polarity, short the S+ and S- terminals on the 1550A calibrator and click the Take Reading button below step 2E. Values will appear in the Amp Zero and Gain indicator fields. Note: After the first channel has been completed, the Abort Calibration is available. Step 3: Finish the system calibration process After measurements for all four channels have been taken, select the Finish Calibration button to complete the system calibration process.

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When the calibration process is complete, “Calibration Complete” displays in the status bar at the bottom of the screen. The system will store the new calibration values in the D4’s internal flash memory, along with the calibration date. Step 4: Retrieve the new calibration data and date (optional) After calibration, you may view, save and print the new calibration date and calibration settings. To view the data, select the Get Current Cal button.

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To save and print a calibration report, select the Save Current Cal Values button. When the Save As window displays, navigate to the desired location in which to save the file. Retain the default file name or change as desired. The default file name for the calibration report is as follows: SSSSSS_YYYY_MM_DD_M-M_Device_Cal_Report.txt, where: SSSSSS is the serial number of the D4, YYYY_MM_DD is the date, and M-M_Device_Cal_Report.txt is the terminator.

When Save is clicked, your default text file viewer, e.g., MS Notepad, will be launched, displaying the calibration report. Both the previous and current calibration data will be included. The file may be printed using the viewer.

Click the Exit Calibration button to end the calibration process.

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5.14 Program Messages Program status and informational messages may be displayed by selecting the File>>Show Activity Log menu item. Messages are added to this log only when it is opened.

5.15 Upgrading Firmware Note: Before upgrading, disable the real-time display. Go to Hardware>>Real Time Display and unselect it if it is checked. To upgrade to a newer version of firmware on the D4, select Hardware>>Update Firmware on the menu. Select the serial number of the D4 to receive the update. (Recording and displays will be halted when selection is made.)

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Model D4 Data Acquisition Conditioner Instruction Manual A file browser appears that lets you select the firmware upgrade file. By default this file is named “158000134_D4.hex”. Typically you will navigate to the latest file provided by Micro-Measurements. After you select OK, a confirmation prompt will appear showing the current firmware version of the D4 and the version that you are attempting to install. If the versions are correct, select OK to continue. A progress bar will display to track the upgrade. While the upgrade is occurring, do not touch the D4 hardware or the software application. You will be requested to powercycle the D4 and restart the application when the upgrade is complete. If you need to upgrade several D4’s, it is okay to choose Restart Later. That way you only need to restart the application once after you have upgraded all of the D4’s. However, power-cycle the D4 immediately. Note: You will be unable to communicate with the D4 until the application has been restarted. If you need to stop the upgrade, it’s okay to pull the plug from the D4. Just do it early on or it will be too late. You will see some error messages; then just close the application, and restart.

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6 Warranty Vishay Measurements Group, Inc. warrants all instruments it manufactures to be free from defect in materials and factory workmanship, and agrees to repair or replace any instrument that fails to perform as specified within three years after date of shipment. Coverage of computers, cameras, rechargeable batteries, and similar items, sold in conjunction with equipment manufactured by Vishay Measurements Group, Inc. and bearing the identifying name of another company, is limited under this warranty to one year after the date of shipment. The warranty on nonrechargeable batteries and similar consumable items is limited to the delivery of goods free from defects in materials and factory workmanship. This warranty shall not apply to any instrument that has been: i. repaired, worked on or altered by persons unauthorized by Vishay Measurements Group, Inc. in such a manner as to injure, in our sole judgment, the performance, stability, or reliability of the instrument; ii. subject to misuse, negligence, or accident; or iii. connected, installed, adjusted, or used otherwise than in accordance with the instructions furnished by us. At no charge, we will repair, at our plant, or an authorized repair station, or at our option, replace any of our products found to be defective under this warranty. This warranty is in lieu of any other warranties, expressed or implied, including any implied warranties of merchantability or fitness for a particular purpose. There are no warranties, which extend beyond the description on the face hereof. Purchaser acknowledges that all goods purchased from Vishay Measurements Group, Inc. are purchased as is, and buyer states that no salesman, agent, employee or other person has made any such representations or warranties or otherwise assumed for Vishay Measurements Group, Inc. any liability in connection with the sale of any goods to the purchaser. Buyer hereby waives all rights buyer may have arising out of any breach of contract or breach of warranty on the part of Vishay Measurements Group, Inc., to any incidental or consequential damages, including but not limited to damages to property, damages for injury to the person, damages for loss of use, loss of time, loss of profits or income, or loss resulting from personal injury. Some states do not allow the exclusion or limitation of incidental or consequential damages for consumer products, so the above limitations or exclusions may not apply to you. The purchaser agrees that the Purchaser is responsible for notifying any subsequent buyer of goods manufactured by Vishay Measurements Group, Inc. of the warranty provisions, limitations, exclusions and disclaimers stated herein, prior to the time any such goods are purchased by such buyer, and the Purchaser hereby agrees to indemnify and hold Vishay Measurements Group, Inc. harmless from any claim asserted against or liability imposed on Vishay Measurements Group, Inc. occasioned by the failure of the Purchaser to so notify such buyer. This provision is not intended to afford subsequent purchasers any warranties or rights not expressly granted to such subsequent purchasers under the law. Vishay Measurements Group, Inc. reserves the right to make any changes in the design or construction of its instruments at any time, without incurring any obligation to make any change whatever in units previously delivered. Vishay Measurements Group, Inc.’ sole liabilities, and buyer’s sole remedies, under this agreement shall be limited to the purchase price, or at our sole discretion, to the repair or replacement of any instrument that proves, upon examination, to be defective, when returned to our factory, transportation prepaid by the buyer, within the applicable period of time from the date of original shipment. Return transportation charges of repaired or replacement instruments under warranty will be prepaid by MicroMeasurements. Vishay Measurements Group, Inc. is solely a manufacturer and assumes no responsibility of any form for the accuracy or adequacy of any test results, data, or conclusions, which may result from the use of its equipment. The manner in which the equipment is employed and the uses to which the data and test results may be put are completely in the hands of the Purchaser. Vishay Measurements Group, Inc. shall in no way be liable for damages consequential or incidental to defects in any of its products. This warranty constitutes the full understanding between the manufacturer and buyer, and no terms, conditions, understanding, or agreement purporting to modify or vary the terms hereof shall be binding unless hereafter made in writing and signed by an authorized official of Vishay Measurements Group, Inc..

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D4 Instruction Manual - strain gages

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