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USB LVDT Signal Conditioner SD20-LVDT

Image SD20-LVDT

The Metrolog SD20-LVDT is a “Plug and Play” USB signal conditioner for industrial, laboratory and academic applications.

Its design allows quick and simple real time readout visualization and signal sample acquisition. No complex setup or calibration procedures are required by the user.

Supplied to the user paired with a specific transducer (LVDT or RVDT), all transducer’s characteristics and calibration data is saved into the device flash memory prior shipment.


  • Compatible with linear and rotary displacement transducers, LVDT and RVDTs
  • Direct power supply from the USB bus for both conditioner and sensor, without the need of external power supply.
  • SD20 DataLogger software included for easy readout visualization and data sample acquisition.
  • State-of-the-art signal conditioner featuring a 24-bit high precision A/D converter and internal linearization lookup table with more than 500,000 reference points.
  • Open communication protocol, allowing user application development and connectivity with many commercial software.

Technical Data

  • Communication Interface: USB (Universal Serial Bus 2.0) with UART serial port virtualization.
  • Sensor compatibility: LVDTs and RVDTs
  • Linearization: Sensor signal linearization based on lookup table (LUT) with total of 524,288 reference points. Linear interpolation between look-up table (LUT) reference points. Modeling and linearization point generation provided by SD20ConfDiag software.
  • LVDT signal conditioner: Sine wave oscillator circuit (5kHz) with low harmonic distortion for sensor excitation. Adjustable excitation signal by factory based on specific transducer requirement (1,7 to 5VRMS). Ratiometric LVDT signal processing with low thermal drift (500Hz bandwidth).
  • Analog to Digital converter: 24-bit high precision A/D converter with precision voltage reference. Primary data sample rate selectable by software from 6.8 to 880 samples per second.
  • Effective digital data throughput: Software selectable transfer rate from 6.88 to 880 reads/s, based on selected primary and secondary filter parameters.
  • Process control tolerance limits: 2 adjustable tolerance limits (upper and lower) with digital output port signaling.
  • Digital Input/Output interface: Digital input interface: 3 optocoupled input ports. Function defined by user. Digital output interface: 2 open-coletor outputs with pull-up. Function defined by user.
  • Power Supply: 4.5 to 5.5VDC, 400mA, supplied direct from the USB bus (or external USB compatible power supply).
  • Storage temperature/operation: 10oC/50oF to 70oC/158oF (storage), 10oC/50oF to 50oC/122oF (operation)
  • Protection Class: IP50, IEC 60529
  • Dimensions/Weight 116 x 80 x 28 mm / 4.6” x 3.2” x 1.1”. 140g / 5oz


  • Cientific data acquisition
  • Accuracy check of Dial gauge and other measurement equipments.
  • Go/No-Go quality control on floor-shops (with or without the use of a computer )
  • Leakage tests
  • Mass and force measurement
  • Dimensional measurements
  • Aplications with high number of transducers

Documents and Files

File Date Size
Signal conditioner SD20 datasheet (English) 09/04/2010 658KB
Signal conditioner SD20-LVDT datasheet (Portuguese) 09/04/2010 658KB
Signal conditioner SD20 manual (English) 20/03/2019 1016KB
Signal conditioner SD20 manual (Portuguese) 20/03/2019 1014KB
Signal conditioner SD20 quick start guide (English) 03/10/2012 97KB
Signal conditioner SD20 quick start guide (Portuguese) 03/10/2012 101KB
Using SD20 conditioner with Q-MAN World Wide software (realease WWE 0007) (Portuguese) 05/04/2010 298KB
SD20 connector assembly and calibration (advanced procedure) (English) 14/09/2012 913KB
Using SD20-LVDT conditioner with multiple LVDT cores (Portuguese) 17/10/2012 653KB
Using the SD20 conditioner with WinCEP 5 software in real time data acquisition (Portuguese) 19/10/2012 370KB
SD20 DataLogger software advanced configuration guide (Portuguese) 16/10/2013 3.0MB
SD20 DataLogger software COM port routing instructions (Portuguese) 06/05/2021 994KB
USB driver 2.12.06 (Windows, certified WHQL setup) 13/08/2015 2.0MB
SD20 update utility for firmware version 2.1 build 0001 09/05/2024 1.0MB
DataEx 1.51 - Free utility to bridge the communication interface with MS Excel, SPC software, among others 25/10/2017 1.2MB
Software SD20 Datalogger v4.2 (setup version) 10/11/2023 7.2MB
Software SD20 Datalogger v4.2 (pocket version) 10/11/2023 7.1MB
Software SIAD MD v1.6.7 (setup version) 06/03/2024 4.5MB
3D model Metrolog SD20 signal conditioner (STEP format) 20/11/2020 952KB