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VTI Instruments EMX-4250 User Manual

Dcv/acv and iepe input 16 / 8 /4 channel 204.8 / 625 ksa/s 24-bit digitizer
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EMX-4250 / EMX-4251
DCV/ACV and IEPE Input 16 / 8 Channel 204.8 kSa/s 24-bit Digitizer
EMX-4016B/ EMX-4016M
16 Channel Breakout Box w Buffer Out / w Bridge Signal Conditioning
DCV/ACV and IEPE Input 4 Channel 625 kSa/s 24-bit Digitizer
ACV, Charge, and IEPE Input 4 Channel 625 kSa/s 24-bit Digitizer
For EMX-425x
EMX-4350
EMX-4380
'
U
M
SER
S
ANUAL
P/N: 82-0142-100
Released Sep 26, 2017
VTI Instruments Corp.
2031 Main Street
Irvine, CA 92614-6509
(949) 955-1894

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  • Page 1 EMX-4250 / EMX-4251 DCV/ACV and IEPE Input 16 / 8 Channel 204.8 kSa/s 24-bit Digitizer EMX-4016B/ EMX-4016M 16 Channel Breakout Box w Buffer Out / w Bridge Signal Conditioning For EMX-425x EMX-4350 DCV/ACV and IEPE Input 4 Channel 625 kSa/s 24-bit Digitizer...

  • Page 2: Table Of Contents

    Break out box Specifications ..........................19 Environmental Specifications ..........................20 ..........................21 HYSICAL HARACTERISTICS Physical Specifications ............................21 EMX-4250/4251, EMS-4016B/ EMX-4016M Connector PIN Numbering ............21 EMX-4250/4251, EMX-4016B/EMX-4016M Connector Pin Assignments ............22 2.................................. 23 ECTION ......................23 ETTING TARTED WITH THE NSTRUMENT Introduction ................................
  • Page 3 www.vtiinstruments.com Driver for Linux OS ............................34 ..............................35 OMPATIBILITY Drivers, Instruments, and OS ..........................35 Driver and Firmware Revisions .......................... 35 Driver API and Instruments ..........................35 ............................... 37 RIVER TRUCTURE Measurement ..............................37 Channels and Channel Groups ..........................37 Start, Arm, Trigger, and Alarm...........................
  • Page 4 VTI Instruments Corp. Analog to Digital Converter (ADC) ........................71 Anti-Alias Filter ..............................71 Flatness ................................75 Group Delay ............................... 77 ................................. 82 CCESSORIES Break-Out-Box (BOB)............................82 Ordering Information ............................85 A ................................86 PPENDIX ..................86 IGITAL ALIAS ILTER AND EASUREMENT Overview ................................

  • Page 5: Certification

    VTI Instruments Corp. shall not be liable for injury to property other than the goods themselves. Other than the limited warranty stated above, VTI Instruments Corp. makes no other warranties, express or implied, with respect to the quality of product beyond the description of the goods on the face of the contract.
  • Page 7 www.vtiinstruments.com Introduction...

  • Page 8: Declaration Of Conformity

    RODUCT ONFIGURATIONS VTI Instruments. declares that the aforementioned product conforms to the requirements of the Low Voltage Directive 73/23/EEC and the EMC Directive 89/366/EEC (inclusive 93/68/EEC) and carries the “CE” mark accordingly. The product has been designed and manufactured according to the following...

  • Page 9: General Safety Instructions

    www.vtiinstruments.com ENERAL AFETY NSTRUCTIONS Review the following safety precautions to avoid bodily injury and/or damage to the product. These precautions must be observed during all phases of operation or service of this product. Failure to comply with these precautions, or with specific warnings elsewhere in this manual, violates safety standards of design, manufacture, and intended use of the product.
  • Page 10 VTI Instruments Corp. ARNINGS Avoid Electric Shock To avoid electric shock or fire hazard, do not operate this product with the covers removed. Do not connect or disconnect any cable, probes, test leads, etc. while they are connected to a voltage source.

  • Page 11: Support Resources

    UPPORT ESOURCES Support resources for this product are available on the Internet and at VTI Instruments customer support centers. VTI Instruments Corp. World Headquarters VTI Instruments Corp. 2031 Main Street Irvine, CA 92614-6509 Phone: (949) 955-1894 Fax: (949) 955-3041...

  • Page 12: Section 1

    ECTION NTRODUCTION VERVIEW The EMX-4250, EMX-4251, EMX-4350 and EMX-4380 (referred to collectively as the “EMX-4250/4350/4380”) are Smart Dynamic Signal Analyzers incorporate best-in-class analog design methodology to deliver industry leading measurement accuracy. This instrument is ideal for a wide range of applications including noise, vibration, and harshness (NVH); machine condition monitoring;...
  • Page 13 Flexible Application Programming Options EMX-4250/4350/4380 module is delivered with an application programming interface (API) that ™ conforms to the industry standard IVI specifications for its class. The IVI drivers port seamlessly ™...

  • Page 14: Preparation For Use

    VTI Instruments Corp. REPARATION FOR NPACKING When an EMX-4250/4350/4380 is unpacked from its shipping carton, the contents should include the following items: • An EMX-4250, EMX-4350, or EMX-4380 • VTI Instruments Distribution CD All components should be immediately inspected for damage upon receipt of the unit. ESD precautions should be observed while unpacking and installing the instrument into a PXI Express chassis.

  • Page 15: Installation

    2) Connect the power supply adaptor, and ensure correct voltage level and necessary grounding 3) Connect the 25 pin Micro D-Sub cables from EMX-4250/51 to the BoB. Observe that J1 & J2 should not be interchanged, if you are using EMX-4250. If you are using EMX-4251, connect...

  • Page 16: Storage And Shipment

    Containers and materials identical to those used in factory packaging are available through VTI Instruments offices. If returning the module to VTI Instruments for service, contact a VTI Service Center to set up an RMA. The following information will be required: •...

  • Page 17: Specifications

    PECIFICATIONS IGITIZER PECIFICATIONS EMX-4250/4251 EMX-4350 EMX-4380 Input Specifications No. of Channels 4250: 16ch / 4251: 8ch 25-pin Micro-D BNC, shell floating from chassis ground Input Connector Molex 83614-9012 Center Pin = HI; Shell = LO Differential Differential Input Type...

  • Page 18: Trigger Input Specifications

    0.1 V: -112 dB; Other Channel-to-Channel Crosstalk, 1 kHz -98 dB Ranges: -122 dB Other Built-In Self-Calibration Yes (Voltage only) 128MBytes 128MBytes On-board Memory EMX-4250: 1.875 MSa/ch 7.5 MSa/ch EMX-4251: 3.75 MSa/ch Table 1.1 Digitizer Specifications RIGGER NPUT PECIFICATIONS EMX-4250/4251 EMX-4350 EMX-4380...

  • Page 19: Break Out Box Specifications

    www.vtiinstruments.com REAK OUT BOX PECIFICATIONS EMX-4016 EMX-4016B EMX-4016M Input Specifications No. of Channels 16 channels 16 channels 16 channels RJ45 connector (8-pin), pinout Input Connector BNC Isolated from Chassis BNC Isolated from Chassis compatible with EX1629 Input Type Differential Differential Differential ±10Vpk Min.

  • Page 20: Environmental Specifications

    VTI Instruments Corp. EMX-4016 EMX-4016B EMX-4016M <0.5mV Typical, <1mV Max. Offset/Zero < 10mV (0°C to +55°C) Typical Stability: ±20uV/°C Output Impedance < 50Ω < 50Ω 30 µVRMS Typical; 30 µVRMS Typical; Noise 60 µVRMS Max 60 µVRMS Max. -3dB: ≥ 200 kHz Typical -3dB: ≥...

  • Page 21: Physical Characteristics

    Center Pin = HI; Shell = LO Pins 5 (Trig) & 18 Trigger Input Connector SMB Male Jack Receptacle (Gnd) EMX-4250/4251, EMS-4016B/ EMX-4016M C PIN N ONNECTOR UMBERING Figure 1-3: EMX-4250, EMS-4016B/ EMX-4016M Input Connector (Front View) Molex 83614-9012 Pin Numbering Introduction...

  • Page 22: Emx-4250/4251, Emx-4016B/Emx-4016M Connector Pin Assignments

    VCALP & VCALN provide the built-in calibration signal out to a BNC in the BOB so it can be connected to a DMM and used during factory calibration. BOB INT is used to let the EMX-4250/4251 know that a BOB has been connected to the digitizer. Molex 83614-9012...

  • Page 23: Section 2

    IVI Shared Components library (for Windows OS only) and the provided VTI Instruments driver. For 32-bit Windows OS, install the 32-bit driver. For Windows 7 (64-bit) and Windows 8 (64-bit), the 64-bit driver installer installs both 64-bit and 32-bit compatible drivers.
  • Page 24 VTI Instruments Corp. Figure 2-1: IVI Shared Component Installation Instrument Driver Installation If the VTEXDigitizer/DSA instrument driver was installed previously on the host PC, proceed to Platform/LXISync Instrument Driver Installation. To install the VTEXDigitizer/DSA instrument driver, navigate to <CD-ROM Drive>:\Drivers\LXI Drivers\EMX Series, on the CD, open the appropriate zip file in this directory, and then run the .msi installer.

  • Page 25: Building And Running Example Programs

    www.vtiinstruments.com The Linux driver (32-bit and 64-bit) is located under <CD-ROM Drive>:\Drivers\Linux Drivers\Linux EMX Series. Find out the version of your operating system and unzip the corresponding version into a folder. Platform/LXISync Instrument Driver Installation NOTE Complete this step only if the LXISync capabilities of the EMX platform are required. Also, if this driver was installed previously on the host PC, software installation is now complete.

  • Page 26: Web Interface

    VTI Instruments Corp. Figure 2-4: Building an Example Linux Examples Linux examples are stored at /opt/vti/share/doc/digitizer/examples/. To build them, copy that folder to a writable location, change directory to the examples folder and run make. ~$ cd /tmp /tmp$ cp -r /opt/vti/share/doc/digitizer/examples/ .

  • Page 27: Card Upgrade Through Web Interface

    NTERFACE Figure 3-2: Firmware Update Using Web Interface The firmware for the EMX-4250/4350/4380’s can be updated from the Upgrade page as shown Figure 3-2. Simply select new firmware image file from the folder in which its kept and click submit button.

  • Page 28: Connecting To Embedded Slot-0 Pxie Controller

    VTI Instruments Corp. Figure 3-3: Selecting Firmware Image to Update Using Web Interface Figure 3-4: After Firmware Image is Updated Using Web Interface After all cards are upgraded, the system must be rebooted for the new firmware to take effect. After system reboot, the details of the cards can be seen in the SFP web page.
  • Page 29 www.vtiinstruments.com Figure 3-7: Sentiel Cards details in Device Manager To connect to a digitizer card from the client source code, first declare its driver variable. IVTEXDigitizerPtr digitizer(__uuidof(VTEXDigitizer)); Call the drivers Initialize function, which will open a connection to the card. This function expects 4 arguments.
  • Page 30 VTI Instruments Corp. _bstr_t option_string = "Cache=False, DriverSetup = preferpcieconnection = true"; _bstr_t resource = "TCPIP::127.0.0.1::slot1_3::INSTR"; digitizer->Initialize(resource,VARIANT_FALSE,VARIANT_TRUE,option_string); // The above call opens a connection to the card plugged in the chassis. // If Initialize call fails, a null value is returned to the driver.
  • Page 31 www.vtiinstruments.com digitizer->Sync->CoordinationLine = "LAN,PXI0"; else digitizer->Sync->CoordinationLine = "PXI0"; digitizer->Sync->Line = "PXI0"; digitizer->Measurement->NumRecordsPerTrigger = records_per_trigger; digitizer->Trigger->TriggerCount = num_triggers; if(digitizer->Initialized) digitizer->Measurement->Abort(); digitizer->Close(); digitizer = NULL; APPENDIX B...

  • Page 32: Section 4

    NTRODUCTION This section describes how to use EMX-4250/4350/4380 using instrument driver. The instrument driver provides an API that allows the user to configure and control the EMX-4250/4350/4380 cards using high level commands. Two types of drivers are available. One is an IVI driver based on the industry standard IVI driver architecture specification.

  • Page 33: Instrument Drivers

    The “Digitizer” drivers are common drivers used by all EMX digitizer cards provided by VTI Instruments. For a simple data acquisition application, the “Digitizer” driver may be the only driver the user needs to use. The “DSA” drivers are essentially a super set of digitizer driver. In addition to the data acquisition functionalities in “Digitizer”...

  • Page 34: Driver For Linux Os

    VTI Instruments Corp. RIVER FOR INUX In addition to the IVI drivers for Windows OS, C++ libraries are provided for the Linux OS compatible with LSB (Linux Standard Base) 4.0 or later. The Linux drivers are supported on distributions running Linux kernel version 2.6.32 or later. In addition, the Linux drivers require GCC version 4.3 or later and glibc 2.11 or later.

  • Page 35: Compatibility

    OMPATIBILITY RIVERS NSTRUMENTS Driver Instruments Operating System Digitizer EMX-4250, EMX-4350, Windows XP, Vista, 7 (32-bit EMX-4380 and 64-bit), 8 (32-bit and 64-bit) Linux (32-bit and 64-bit) EMX-4250, EMX-4350, Windows XP, Vista, 7 (32-bit EMX-4380, EMX-1434 and 64-bit), 8 (32-bit and 64-bit)
  • Page 36 VTI Instruments Corp. Digitizer/DSA APIs EMX-4250 EMX-4350 EMX-4380 Events Supported Supported Supported Measurement Supported Supported Supported Multipass, Oversample Multipass, Oversample Multipass, Oversample not supported not supported not supported Platform Supported Supported Supported ReferenceOscillator Supported Supported Supported OutputEnabled is not OutputEnabled is not...

  • Page 37: Driver Structure

    36 analog input channels, one channel group object for all 32 EMX-4250 inputs, and one channel group for all EMX-4350 inputs. These channel groups are named as “All”, “EMX-4250”, and “EMX-4350”.

  • Page 38: Start, Arm, Trigger, And Alarm

    TART RIGGER LARM EMX-4250/4350/4380 implements sophisticated Arm/Trigger model as shown in Figure 4-1. This trigger model conforms industry standard trigger models defined in the IVI Digitizer specification or LXI Sync specification with some additional features. Figure 4-1: Trigger Model Sync Sync is an event that synchronizes the entire system.
  • Page 39 www.vtiinstruments.com Start Once the measurement is initiated by the Initiate command, instrument completes all preparation and becomes ready to start taking data immediately and then the state machine moves to the Wait for Start state. The Start interface provides methods and properties to advance to the next state. The amount of time it takes to reach to Wait for Start after measurement Initiate command varies depending on the measurement configuration.
  • Page 40 VTI Instruments Corp. Pre-Trigger Re-arm Time Samples Waveform Record Sample Interval Trigger Holdoff First data point Trigger Offset Trigger Delay < 0 InitialX < 0 Trigger Figure 4-3: Negative Trigger Delay The TriggerCount property defines how many times the trigger events are accepted and data blocks are acquired.

  • Page 41: Retrieving Data

    Data Acquisition section for more information. Streaming Streaming data is an alternative method for retrieving data from the EMX-4250/4350/4380. Unlike the FIFO read function, instruments send new data records to the host PC as soon as it becomes available when streaming data. The data is kept in the host memory buffer managed by Digitizer/DSA driver.

  • Page 42: Reference Clock And Time Stamp

    LAN E VENTS When the EMX-4250/4350/4380 is used with EMX-2500 Ethernet controller (and optionally with Platform driver), it can act as an LXI device. These instruments can be synchronized to an IEEE 1588 PTP grand master clock. They can be armed or triggered by LAN events or they can generate LXI LAN events to synchronize with other LXI devices through LXI Sync interface defined by IVI standard.

  • Page 43: Ivi Class Compliant Interfaces

    www.vtiinstruments.com IVI C LASS OMPLIANT NTERFACES In addition to the IVI-LXISync interface, the VTEXDigitizer driver exposes the IVI-Digitizer and IVI-Scope class compliant interfaces. These interfaces are exposed for the instruments interchangeability. However, these interfaces are currently not supported. APPENDIX B...

  • Page 44: Multiple Cards , Segments , And Chassis

    Unlike many typical instruments driver, both the Digitizer and DSA drivers treat multiple EMX-4250/4350/4380 cards as a single, collective instrument. The user can initialize a single driver for two EMX-4250 cards and treat them as a single, 32 channel instrument instead of creating two driver sessions with 16 input channels each.

  • Page 45: Multiple Segment Measurement

    www.vtiinstruments.com PXIe 100MHz PXI 10MHz STAR/DSTAR Trigger PXI0-7 Bus Segment PXI0-7 Bus Segment PXI0-7 Bus Segment Figure 4-7: PXIe Chassis and Trigger Bus ULTIPLE EGMENT EASUREMENT In order to synchronize all cards installed on multiple trigger segments, trigger line between bus segments must be bridged together using the Routes interface in Platform driver.

  • Page 46: Multiple Chassis Synchronization With Lan Events

    When chassis are geographically separated by a long distance, it may not be practical to connect a physical trigger and a reference clock line between them. The EMX-2500 makes EMX-4250/4350/4380s in each chassis an LXI device so they can be synchronized together using IEEE 1588 clock and LAN events.
  • Page 47 ReferenceOscillator. Source and TimestampSource properties must be set to “System” (IEEE 1588). Once these steps have been completed, the EMX-4250/4350/4380’s Sync.CoordinationLine property must be set to “LAN,PXI0”. Once this has been performed, the EMX-4250/4350/4380’s state transitions will be automatically coordinated by LAN events between chassis and PXI0 trigger line within chassis.

  • Page 48: Data Acquisition

    VTI Instruments Corp. CQUISITION The EMX-4250/4350/4380 instruments have a dedicated A/D converter at each analog input channel. The A/D converter samples analog data at fixed frequency specified by a multiple of the ClockFrequency (F ). The output data rate of the ADC is F .

  • Page 49: Data Streaming

    FIFO Overflow Limit Figure 4-12: Circular FIFO The EMX-4250/4350/4380 implements three different FIFO modes of operation in order to meet varieties of application needs. The FIFO mode defines the behavior when the FIFO buffer is full and there is no more space to write new data records.

  • Page 50: Sampling Rates

    VTI Instruments Corp. If another type of streaming is enabled while memory streaming is enabled, memory streaming is disabled unless the MemoryChannelList property is set. Disk Streaming Disk streaming is intended for high performance applications and/or long acquisitions. When enabled by setting a filename, the driver optimizes the data path by not converting the data from the native VRT data format, but, instead, delivering it as directly as possible from the network socket to the disk.
  • Page 51 Trigger Figure 4-13: Record Size and NumRecordsPerTrigger With EMX-4250/4350/4380, the minimum RecordSize is 1 and the maximum power of 2 RecordSize is 32768. Since each data packet transferred from the instrument to the host contains one data record from each ADC channel, in general, the user can achieve higher data transfer using a larger RecordSize value due to reduced overhead, but this affects the data update interval, as the amount of time to acquire one data record is: T = RecordSize/SampleRate.

  • Page 52: Overloads And Open Transducer Detection

    Table 4-2: Instrument-Specific Fault Status Bit Support TAMP During data acquisition, the EMX-4250/4350/4380 returns timestamps along with digitized analog data. The timestamps are created based on the TimestampSource clock specified in ReferenceOscillator interface. When IEEE 1588 synchronized time stamps are desired, the TimestampSource property must be set to ReferenceOscillatorTimestampSourceSystem.

  • Page 53: Additional Data

    www.vtiinstruments.com of the first data sample in each retrieved data record. The time of trigger event is returned in the AdditionalData parameter. Timestamp Source Timestamp value Resolution System (IEEE 1588) PTP or TAI (International Atomic Time) 20 ns PXIe_CLK100 Elapsed time from last SYNC 20 ns PXI_CLK10 Elapsed time from last SYNC...

  • Page 54: Measurement Process

    VTI Instruments Corp. EASUREMENT ROCESS EASUREMENT ETUP After the instruments are initialized by driver Initialize method, or the previous measurement is finished, the instrument is in Idle state. While in the Idle state, the user prepares for the next data acquisition by configuring the setup parameters.

  • Page 55: Arming

    PXI trigger line (PXI0-7) as an arm source. Arming from LAN Events by Other Instruments The user, or another LXI device, can send LAN events to arm the EMX-4250/4350/4380s using the digitizer/DSA driver. Alternatively, a LAN event can be sent to the EMX-2500 controller using the platform driver.

  • Page 56: Data Retrieval

    PXI trigger lines (PXI0-7) as a trigger source. Triggering from LAN Events by Other Instruments The user, or other LXI device, can send a LAN event to trigger the EMX-4250/4350/4380s using the digitizer/DSA driver. Alternatively, the LAN event can be sent to the EMX-2500 controller using the platform driver.

  • Page 57: Events

    Table 4-5: FIFO Buffer Update Rate (Seconds) VENTS Events are an optional feature allowing the EMX-4250/4350/4380 to send notifications to the user, or other instruments, when a specified event occurs. The notification can be via LAN message or a PXI trigger line. The user can specify an event when the measurement state is armed, triggered, or finished.

  • Page 58: Using With Emx-1434

    EMX-1434 SING WITH This section describes how the EMX-1434 can be used together with the EMX-4250/4350/4380 instruments. See EMX-1434 User’s Manual for more detail information for this instrument. Currently, EMX-1434 is configured and controlled by DSA driver. When both EMX-1434 and EMX-4250/4350/4380 modules are included in a single DSA driver session, they work synchronously.
  • Page 59 The array of time stamps can be used to resample the data from EMX- 4250/4350/4380’s for synchronous measurement. Figure 4-18: Resampling ADC data by tachometer pulses VTI provides a separate library to resample data acquired by EMX-4250/4350/4380 and other VTI digitizer. APPENDIX B...

  • Page 60: Digital Input And Output

    VTI Instruments Corp. IGITAL NPUT AND UTPUT The EMX-1434 has 4-bit DIO channels. The digital signal can be associated to the EMX-4250/4350/4380 measurement data record. Optionally, DIO value can be used as an arming condition of the measurement. APPENDIX B...

  • Page 61: Where To Find More Information

    User’s Manuals are available for the EMX-2500, CMX09, CMX18, and EMX-1434. PECIFICATION NFORMATION EMX-4250/4350/4380 conforms to many industry standards in both hardware and software architecture. Although products can be used without knowing these standards, some knowledge can be useful to take full advantage of VTI Instruments products.

  • Page 62: Section 5

    VTI Instruments Corp. SECTION 5 IGITIZER ODULE ESCRIPTIONS VERVIEW The Smart Dynamic Signal Analyzers family of products incorporates best-in-class analog design methodology to deliver industry leading measurement accuracy. These instruments are ideal for a wide range of applications including noise, vibration, and harshness (NVH); machine condition monitoring;...

  • Page 63: Block Diagrams

    24-bit ADC Decimating 20V,10V,1V,0.1V Dig. Filter Charge Amplifier Gain & Offset PXIe Mezzanine Calibration 1mV/pC Main PCB Figure 4-19: EMX-4380 Block Diagram EMX-4250/4251 Block Diagram Self- IEPE TEDS +24V Bias Test 204.8ksps LPF3 24-bit ADC Decimating 10V,5V, 2V, 1V, Dig. Filter 0.5V, 0.2V, 0.1V...

  • Page 64: Input Types

    DC path to ground through some resistance to make sure the common mode voltage stays close to ground. The EMX-4250/51 have 25pin microD connectors and voltage signals applied to each input channels using EMX-4016/EMX-4016B/EMX-4016M Break out box. These Break out boxes pass through the signals directly from the input BNC connector to the 25pin microD connected to the EMX-4250/51 without any signal conditioning.
  • Page 65 Channels that do not have a current source enabled can be used for standard voltage measurements. The EMX-4250’s input is set to pseudo-differential when set to IEPE. The LO side of the input is shunted to amplifier signal ground through a 100 Ω resistor.
  • Page 66 VTI Instruments Corp. 4.5mA,5V,0.5dB 10mA,5V,0.5dB Cable Length (ft) Figure 4-6 –Frequency Response of IEPE Sensor Affected by Cable Length Charge (EMX-4380) The charge amplifier is used to convert the charge output (in picocoulombs - pC) from Piezo-Electric (PE) transducers to volts. IEPE sensors are PE transducers with built-in charge amplifiers. PE sensors are used in high temperature environments where the built-in electronics cannot survive or operate poorly such as inside jet engines.
  • Page 67 www.vtiinstruments.com isolation is OFF, the input of the charge amplifier operates in single-ended mode with LO side connected to digitizer ground. The accuracy in the pass-band of the charge converter is not dependent on cable capacitance Csh. This would not be the case if the front-end is a voltage amplifier instead of a charge amplifier since Csh together with Cin would be an attenuation stage.

  • Page 68: Break Out Box Output

    The EMX-4016B/EMX-4016M BoB provides only one output per channel, which is directly fed into EMX-4250/51 card. The EMX-4016B BoB is designed to provide, buffered analog output per each input channel, in addition to feed into EMX-4250/51 card. For some high reliability applications, IEPE signal conditioning Break-out-Box should have dual analog outputs, to support system level functions, such as redundant recording, real time monitoring, independent control, etc.

  • Page 69: Bridge Transducer

    25pin Micro D-Sub connectors, which are located at the rear side of BoB. The buffered output BNC connectors are also located on the rear panel. NOTE: Buffer output in the 4016M will not work if the EMX-4250 is set to IEPE mode. RIDGE...

  • Page 70: Iepe Input Fault Detection

    OPEN or SHORT and the module is set to IEPE and the fault can also be read through software. The EMX-4250 & EMX-4251 can control the fault LED in the EMX-4016 16-channel break-out- box (BOB). This is done through the I2C serial communication lines available in the 25-pin input connector.

  • Page 71: Analog To Digital Converter (Adc)

    The table below shows the available data rates at which the ADC runs for each model. Oversampling Ratio ( f DATA Oversampling Model Data Rate (f ) - Samples per Second (SPS) Clock (f DATA 131,072 65,536 32,768 4,194,304 Hz EMX-4250 EMX-4251 204,800 102,400 51,200 6,553,600 Hz 409,600 204,800 102,400 51,200 13,107,200 Hz EMX-4350 524,288...
  • Page 72 VTI Instruments Corp. The digital low-pass filter is not effective at f ± 0.58*f so additional analog low-pass filtering DATA is provided to eliminate signals with frequencies in these bands. The corner frequency of the analog anti-aliasing low-pass filter is fixed regardless of the selected data rate. The table below shows the critical frequencies for each data rate at which aliasing can occur and at which the analog low-pass filter needs to provide attenuation.
  • Page 73 0.1V -108 1E+3 1E+4 1E+5 1E+6 1E+7 1E+8 Frequency (Hz) Figure 4-26: EMX-4350/4380 Voltage Amplitude Frequency Response EMX-4250/4251 Anti-Aliasing Figure 4-274: EMX-4250/4251 ADC Digital Filter Freq. Response for f ÷1 DATA APPENDIX B...
  • Page 74 VTI Instruments Corp. Figure 4-28: EMX-4250/4251 ADC Digital Filter Freq. Response for f ÷2 & ÷4 DATA -102 1E+3 1E+6 2E+6 3E+6 4E+6 5E+6 6E+6 7E+6 8E+6 9E+6 Frequency (Hz) Figure 4-29: EMX-4250/4251 Voltage Amplitude Frequency Response APPENDIX B...

  • Page 75: Flatness

    www.vtiinstruments.com LATNESS EMX-4350/4380 Flatness Frequency Response Figure 4-30: EMX-4350/4380 ADC Digital Filter Transition Band 0.1V 0.05 0.00 -0.05 -0.10 -0.15 -0.20 -0.25 -0.30 0.0E+0 5.0E+4 1.0E+5 1.5E+5 2.0E+5 2.5E+5 3.0E+5 3.5E+5 4.0E+5 Frequency (Hz) Figure 4-31: EMX-4350/4380 Voltage Flatness Frequency Response APPENDIX B...
  • Page 76 0.0E+0 5.0E+4 1.0E+5 1.5E+5 2.0E+5 2.5E+5 3.0E+5 3.5E+5 Frequency (Hz) Figure 4-32: EMX-4380 Charge 10 kpC Range Flatness Frequency Response EMX-4250/4251 Flatness Frequency Response Figure 4-33: EMX-4250/4251 ADC Digital Filter Transition Band for f ÷2 and ÷4 DATA APPENDIX B...

  • Page 77: Group Delay

    -0.30 -0.35 -0.40 -0.45 -0.50 2.0E+4 4.0E+4 6.0E+4 8.0E+4 1.0E+5 1.2E+5 1.4E+5 1.6E+5 1.8E+5 2.0E+5 Frequency (Hz) Figure 4-34: EMX-4250/4251 Voltage Flatness Frequency Response ROUP ELAY 0.1V 4.5E-7 4.4E-7 4.3E-7 4.2E-7 4.1E-7 4.0E-7 3.9E-7 3.8E-7 3.7E-7 3.6E-7 3.5E-7 0E+0 5E+4...
  • Page 78 VTI Instruments Corp. 1.20E-6 1.15E-6 1.10E-6 1.05E-6 1.00E-6 9.50E-7 9.00E-7 8.50E-7 8.00E-7 0E+0 2E+4 4E+4 6E+4 8E+4 1E+5 1E+5 1E+5 2E+5 2E+5 2E+5 Frequency (Hz) Figure 4-36: EMX-4250/4251 DC Coupling Voltage Group Delay Frequency Response APPENDIX B...
  • Page 79 www.vtiinstruments.com 1E+3 1E+4 1E+5 1E+6 Frequency (Hz) Figure 4-374: EMX-4016M Magnitude Frequency Response 1E+3 1E+4 1E+5 1E+6 1E+7 Frequency (Hz) Figure 4-385: EMX-4016M Magnitude % Deviation from Nominal vs. Frequency APPENDIX B...
  • Page 80 VTI Instruments Corp. -135 -180 -225 -270 -315 1E+3 1E+4 1E+5 1E+6 1E+7 Frequency (Hz) Figure 4-395: EMX-4016M Nominal Phase Frequency Response -0.5 -1.0 -1.5 -2.0 -2.5 1E+3 1E+4 1E+5 1E+6 1E+7 Frequency (Hz) Figure 4-406: EMX-4016M Phase Deviation (Degrees) from Nominal vs. Frequency...
  • Page 81 www.vtiinstruments.com 0.0 Ω 200.0 Ω 400.0 Ω 1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 1.0E+4 2.0E+4 3.0E+4 4.0E+4 5.0E+4 6.0E+4 7.0E+4 8.0E+4 9.0E+4 1.0E+5 1.1E+5 1.2E+5 1.3E+5 1.4E+5 1.5E+5 Frequency (Hz) Figure 4-417: EMX-4016M Magnitude Frequency Response vs. Lead Wire Resistance APPENDIX B...

  • Page 82: Accessories

    (BOB) REAK VTI offers a series of Break-Out-Boxes (BOB) for use with the EMX-4250 and EMX-4251. There are 8-channel (EMX-4008), 16-channel (EMX-4016 & EMX-4116), and 32-channel (EMX-4032) versions. The BOBs convert the EMX-4250 micro-D Molex input connector into BNC input connectors.
  • Page 83 www.vtiinstruments.com Figure 4-429: EMX-4016B Break-Out-Box Figure 4-30: EMX-4016M Break-Out-Box APPENDIX B...
  • Page 84 VTI Instruments Corp. Figure 4-31: EMX4016B Outline Drawing Figure 4-32:Drawing Represent APPENDIX B...

  • Page 85: Ordering Information

    Digitizer, 24-bit, 4Ch, 625.0 kSa/s IEPE/Volts 70-0409-004 EMX-4380 Digitizer, 24-bit, 4Ch, 625.0 kSa/s IEPE/Volts/Charge 70-0409-011 Break-Out-Box (BOB), 16Ch, for EMX-4250/4251, 1U 19” Rack mount 70-0409-015 EMX-4016 EMX-4016B Break-Out-Box (BOB), 16Ch, w Buffer output ,for EMX-4250/4251, 1U 70-0409-215 19” Rack mount...

  • Page 86: Ppendixa

    The EMX-4250/4350/4380 implements ÷2 decimation filters along with an optional ÷5 decimation filter. These filters are linear phase FIR filter with very low pass-band ripple and high dynamic range even after sixteen stages of filtering.

  • Page 87: Sample Rates And Nominal Spans

    Table A-1: Nominal Span (Sample Rate / 2.56) ROUP ELAYS With EMX-4250/51, a filter in A/D converter introduces 39 samples group delay, and with for EMX-4350/4380 it is 28 samples. This delay is about 45 µs at 625000 Hz. APPENDIX B...
  • Page 88 VTI Instruments Corp. For lower decimated spans, at each stage of 1/2 decimation filter adds 31.5 samples group delay, and 1/5 decimation filter adds 73 samples delay. The total group delay is shown in the table below. Model EMX-4350/4380 EMX-4250/4251...

  • Page 89: Appendixb

    ORRECTION VERVIEW The Fourier transform of the time domain signal acquired by EMX-4250/4350/4380 gives the amplitude and phase of each frequency components. The amplitude indicates the magnitude of the phenomena and the phase represents the time shift. When the instrument acquire signal, the analog signal goes through multiple stages of analog and digital filters before the data reaches to the user’s...

  • Page 90: Ac Coupling Filter

    VTI Instruments Corp. Trigger Event Sub-Sample Delay First Sample Trigger Data Timestamp Timestamp Figure B-6-1: Sub-sample Trigger Delay AC C OUPLING ILTER When the analog signal is measured in AC coupling mode, the analog AC coupling, high-pass filter adds non-linear phase. This delay can be significant, and the amount of delay is frequency dependent.

  • Page 91: Appendixc

    www.vtiinstruments.com PPENDIX TEDS VERVIEW TEDS (Transducer Electronic Data Sheets) is a smart transducer standard defined as IEEE 1451.4. The TEDS is a memory device attached to the IEEE 1451.4 compatible transducer that stores the information of the smart transducer including the transducer identification, sensitivity, calibration, and manufacturer information.
  • Page 92 VTI Instruments Corp. TEDS data is stored in EEPROM. The first 64-bit is “Basic” TEDS data followed by the transducer specific data. The transducer specific information must be parsed using the template provided by the transducer manufacturer. Basic TEDS (64bit)

  • Page 93: Micro Lan (Mlan)

    WARNING The scratchpad will be erased if you unplug your MLAN device, power off the instrument, or wait a significant amount of time between commands. VTI Instruments recommends performing scratchpad operations in a production environment using the “write_and_copy” atomic command which is discussed in detail later.

  • Page 94: Programming Mlan

    TEDS enabled at a time. All other channels must be set to False. After this occurs, the Channel.TEDS interface’s ReadURN(), WriteTEDS(), and ReadTEDS() functions can be used. The WriteTEDS() and ReadTEDS() functions allow the EMX-4250/4350/4380 card to act as an MLAN Repeater (see Maxim APPLICATION NOTE 2966 for the MLAN Repeater specification).
  • Page 95 www.vtiinstruments.com These are the actual opcodes for four of the five functions we outlined above. They are 1-wire bus commands that are sent to the 1-wire (TEDS) devices. The GET_URN function is not listed because it is not a single opcode that modifies data on the device or returns data except for the serial number/URN.
  • Page 96 VTI Instruments Corp. 02 84 00 The first line indicates that the driver call used to send the data was successful. The second indicates how long the packet sent was: 3 bytes, which is what was expected. The next line is the printout of the packet.

  • Page 97: Ds2430 Commands

    www.vtiinstruments.com // send the commands digitizer->Channels->Item[name]->TEDS- >WriteTEDS(WriteBuf.GetSafeArrayPtr()); std::wcout << "Read URN (WriteData)" << std::endl; PrintPacket(WriteBuf); // retrieve the response for each command CComSafeArray<short> ReadBuf; SAFEARRAY* psaReadBuf; digitizer->Channels->Item[name]->TEDS- >ReadTEDS(&psaReadBuf); std::wcout << "Read URN (ReadData)" << std::endl; ReadBuf.Attach(psaReadBuf); PrintPacket(ReadBuf); As in the pervious example, the first byte is reserved for length and increments our index as commands are inserted into the packet.
  • Page 98 VTI Instruments Corp. if(strlen(data) != ((DS2430_SCRATCHPAD_LEN * 2) + (DS2430_SCRATCHPAD_LEN-1))) //(SCRATCHPAD_LEN*2)+(SCRATCHPAD_LEN-1) = 95 printf("Data was not the right length (wanted 95, got %i)\n", (int)strlen(data)); return WriteBuf.Add((short)0); // reserve first byte for length // access the current device with address in DATA_ID WriteBuf.Add(CMD_ML_ACCESS);...
  • Page 99 www.vtiinstruments.com When the ASCII data format used in the example code is seen., the reason for the (SCRATCHPAD_LEN * 2) + (SCRATCHPAD_LEN - 1) code segment becomes more clear. For the DS2430, a data string for the example code might look like this: "01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1F 20 21"...
  • Page 100 VTI Instruments Corp. READ_SCRATCHPAD_2430 The READ_SCRATCHPAD command is nearly identical between the DS2430 and DS2431, but some differences exist. The DS2430 will be covered first. read_scratchpad_2430(IVTEXDigitizerPtr digitizer) recLen = 0; CComSafeArray<short> WriteBuf; WriteBuf.Create(); WriteBuf.Add((short)0); // reserve first byte for length // access the current device with address in DATA_ID WriteBuf.Add(CMD_ML_ACCESS);...
  • Page 101 www.vtiinstruments.com Here is some example output from READ_SCRATCHPAD using the example code: sent packet without errors Packet length: 8 07 82 0A 03 22 AA 00 85 got a packet without errors on receive Packet length: 39 26 82 00 0A 22 AA 00 AA 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1F 20 21 This is identical to what was written with the WRITE_SCRATCHPAD command, so the data was...
  • Page 102 VTI Instruments Corp. ReadBuf.Attach(psaReadBuf); PrintPacket(ReadBuf); recLen = (int)ReadBuf.GetCount(); return recLen; Once again, the first three bytes are the same as WRITE_SCRATCHPAD and READ_SCRATCHPAD. Our block length is 3, as the expected response length, the COPY_SCRATCHPAD command, and the “validation key” that ensures we are not writing to the wrong device are sent.
  • Page 103 www.vtiinstruments.com // send the commands digitizer->Channels->Item[name]->TEDS- >WriteTEDS(WriteBuf.GetSafeArrayPtr()); std::cout << "DS2430 Read Memory (WriteData)" << std::endl; PrintPacket(WriteBuf); // retrieve the response CComSafeArray<short> ReadBuf; SAFEARRAY* psaReadBuf; digitizer->Channels->Item[name]->TEDS->ReadTEDS(&psaReadBuf); std::cout << "DS2430 Read Memory (ReadData)" << std::endl; ReadBuf.Attach(psaReadBuf); PrintPacket(ReadBuf); recLen = (int)ReadBuf.GetCount(); return recLen; Again, the first three are the same as those seen in previous examples.
  • Page 104 VTI Instruments Corp. recLen = 0; CComSafeArray<short> WriteBuf; WriteBuf.Create(); if(strlen(data) != ((DS2430_SCRATCHPAD_LEN * 2) + (DS2430_SCRATCHPAD_LEN-1))) printf("Data was not the right length (wanted 95, got %i)\n", (int)strlen(data)); return WriteBuf.Add((short)0); // reserve first byte for length // access the current device with address in DATA_ID WriteBuf.Add(CMD_ML_ACCESS);...

  • Page 105: Ds2431 Commands

    www.vtiinstruments.com // retrieve the response CComSafeArray<short> ReadBuf; SAFEARRAY* psaReadBuf; digitizer->Channels->Item[name]->TEDS->ReadTEDS(&psaReadBuf); std::cout << "DS2430 Write & Copy Scratchpad (ReadData)" << std::endl; ReadBuf.Attach(psaReadBuf); PrintPacket(ReadBuf); recLen = (int)ReadBuf.GetCount(); return recLen; If one looks closely, it becomes obvious that the WRITE_AND_COPY command is simply a WRITE and a COPY command combined.
  • Page 106 VTI Instruments Corp. len = buf.GetCount(); printf("Packet length: %i\n", (int)len); for(int i = 0; i < len; i++) printf("%02X ", buf[i]); printf("\n"); CRC Checking The CRC check function is called to calculate a CRC16 for the written data and the read data on the DS2431.

  • Page 107: Appendixd

    In order to ensure the measurement accuracy, the analog gain and offset must be regularly calibrated. This is especially true when significant temperature changes occurred since the last time the instruments was calibrated. With the EMX-4250/51, EMX-4350, and EMX-4380, the user can perform calibration using internal reference signal. This is called self-calibration. For self- calibration to work properly, the reference calibration signal should be calibrated annually.

  • Page 108: Self/Full Calibration Adjustments File

    VTI Instruments Corp. adjustments are stored in human readable JSON format. If necessary, the user can edit the constants and keep them as full-calibration. To perform factory calibration, a fully calibrated precision instrument and setup is required. The factory calibration is usually generated by VTI or authorized calibration facility. If the user wishes to perform factory calibration at their own facility, contact to VTI for more information.

  • Page 109: Self Calibration Log

    www.vtiinstruments.com ALIBRATION The calibration log simply consists of a series of informational messages about the progress of calibration, each accompanied by a timestamp. The following are some of the types of message that can appear: • connect to localhost:9900: Setting up the socket to read data from the instrument •...

  • Page 110: Self/Full Calibration Report

    VTI Instruments Corp. • Stdev: A list of the standard deviations from each of the records acquired during the measurement • Reading: The final measurement value, obtained by averaging all the samples of all records acquired during the measurement ALIBRATION...
  • Page 111 www.vtiinstruments.com • Charge Gain Channel – the channel that the adjustment is for Value – The new calculated value of the adjustment Minimum – the minimum allowed value of the adjustment Maximum – the maximum allowed value of the adjustment Error Ratio –...

  • Page 112: Appendixe

    VTI Instruments Corp. PPENDIX ULTIPLE HASSIS YSTEM VERVIEW When a large number of measurement channels is required, or when a distance between measurement points are large, instruments may need to be distributed among more than one chassis. In order to achieve synchronized, simultaneous the data acquisition between instruments, both sampling clock and the measurement state machine transition must be synchronized.

  • Page 113: Synchronization Performance

    www.vtiinstruments.com YNCHRONIZATION ERFORMANCE Two histograms show typical synchronization error between two chassis using trigger cable, and LAN event . When the chassis are synchronized by dedicated cable, the error is mainly determined by signal transmission delay caused by signal routing and cable length. Figure E-1: Typical chass-to-chasss phase error (in degrees) at 1kHz With LAN synchronization, unlike by cable, the error is usually distributed around zero.
  • Page 114 VTI Instruments Corp. Grandmaster Boundary or Transparent Clock Ethernet Boundary Clock Boundary or Transparent Clock Boundary Clock Boundary or Transparent Clock Figure E-2: IEEE1588 Network Topology APPENDIX D...

  • Page 115: Appendixf

    1x16 MB Flash Firmware None EMX-4250 (MFG: Spansion EMX-4251 Backup Firmware None P/N: EMX-4350 Instrument None S25FL128SAGNFI90x EMX-4380 Identity (EMX-4250/4251) or Factory Full None S25FL129P0XNFI00 Calibration (EMX-4350/4380)) User Full VTEXDigitizer.Calibration. Calibration Full.ClearSavedAdjustments() Self Calibration VTEXDigitizer.Calibration. Self.ClearSavedAdjustments() Stored Instrument VTEXDigitizer.Configuration. Configuration...

  • Page 117: Index

    www.vtiinstruments.com NDEX AC Coupling ................66 ICP ....................62 Accuracy ..................16 IEPE ..................16, 62 ADC .....................68 Input Specifications ..............16 Alarm ...................37 isolation ..................63 Anti-Alias Filter ................68 Isolation ..................18 Arming ..................52 Isotron ..................62 Balance ..................18 LAN Events ................39, 43 Bandwidth ................
  • Page 118 VTI Instruments Corp. Slew Rate ..................16 Trigger ............... 17, 36, 42, 52 source capacitance ................64 Span ..................48, 83 Specifications ................16 Upgrade ..................27 Stimulus..................55 Streaming ................38, 46 Synchronization ................42 WEEE .................... 7 Weight ..................21 WRITE_AND_COPY_SCRATCHPAD Tachometer ...................55 DS2430 ................

This manual is also suitable for:

Emx-4251Emx-4016bEmx-4380Emx-4016mEmx-4350

Table of Contents