Signal Conditioning

LiM-4-20 Transmitter Module

LiM-4-20 Transmitter Module

The LiM-420 is an LVDT/RVDT signal conditioning transmitter specifically designed for the OEM marketplace. Operating on an 18 to 30VDC unipolar supply voltage, the LiM-420 delivers a low noise 4 to 20mA output signal. Compatible with many 5 and 6 electrical connection LVDT and RVDT transducers (see specifications), this compact transmitter  provides excellent performance on a budget. A generous excitation drive current of 20mA, allowing operation with transducer input impedances as low as 175 Ohms.

The LiM-420 is designed for easy installation, plugged into a backplane-type connector, or with individual wires connected to the screw terminal barrier strip. Measuring less than 2.5 x 2.5 inches, the LiM-420 may be mounted or stacked using the permanently attached threaded standoffs, or card-edge guides. All six selectable gain ranges are easily accessed via DIP switches and two multi-turn potentiometers allow for fine zero and gain adjustments.



  • Low cost OEM 4-20mA (3-wire) transmitter
  • Very compact, open PC board design
  • DIP switch selectable coarse gain
  • Zero and span adjustment potentiometers
  • 18 to 30VDC supply voltage
  • -25o to +85oC operating temperature range
  • Card-edge or barrier strip connections
  • Works with very low input impedance LVDTs and RVDTs



  • Low cost/high performance
  • Wide operating temperature range
  • Six selectable gain ranges
  • 20-turn zero & gain adjustment potentiometers
  • Threaded standoffs for panel/box mounting



  • Valve position feedback
  • Roller gap sensing
  • Paper head box position
  • Coater knife gap
  • Materials testing machines