LiM-420 Current Output LVDT/RVDT OEM Signal Transmitter SPECIFICATIONS 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 o o -25 to +85 C operating temperature range Card-edge or barrier strip connections Works with very low input impedance LVDTs and RVDTs 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 FEATURES a low noise 4 to 20mA output signal. Compatible with many 5 and 6 electrical connection LVDT and RVDT transducers (see Low cost/high performance specifications), this compact transmitter provides excellent Wide operating temperature range performance on a budget. A generous excitation drive current Six selectable gain ranges of 20mA, allowing operation with transducer input impedances 20-turn zero & gain adjustment as low as 175 Ohms. potentiometers Threaded standoffs for panel/box The LiM-420 is designed for easy installation, plugged into a mounting backplane-type connector, or with individual wires connected to the screw terminal barrier strip. Measuring less than 2.5x2.5 inches, the LiM-420 may be mounted or stacked using the APPLICATIONS permanently attached threaded standoffs, or card-edge guides. All six selectable gain ranges are easily accessed via DIP Valve position feedback switches and two multi-turn potentiometers allow for fine zero Roller gap sensing and gain adjustments. Paper head box position Coater knife gap Materials testing machines SENSOR SOLUTIONS /// LiM-420 Rev 6 07/2017 Page 1 LiM-420 Current Output, LVDT/RVDT OEM Signal Transmitter PERFORMANCE SPECIFICATIONS ELECTRICAL SPECIFICATIONS Supply voltage 18 to 30VDC (unipolar) Supply current 50mA maximum Output range 4 to 20mA Temperature coefficient of output 0.02% of FSO per F 0.036% of FSO per C over operating temperature range Maximum loop resistance 500 (with 24VDC supply) Output noise and ripple 25A RMS maximum Frequency response 50Hz -3 dB Non-linearity 0.05% of FSO Stability 0.05% of FSO maximum (after 30 minute warm-up) Zero adjustment range 2.5mA Transducer excitation Voltage 3.5 VRMS 10%, sine wave Current 20mA RMS maximum Frequency 2.5kHz Transducer requirements Transducer type LVDT or RVDT with 5 or 6 electrical connections LVDT/RVDT input impedance 175 minimum LVDT/RVDT output range 0.1 to 5.6 VRMS for 20mA full scale output ENVIRONMENTAL AND MECHANICAL SPECIFICATIONS Operating temperature range -13F to +185F -25C to 85C Storage temperature range -40F to +257F -40C to 125C Gain adjustment 6 DIP switch selectable ranges 20-turn fine adjustment potentiometer Zero adjustment 20-turn fine adjustment potentiometer Electrical connections PC board edge (to backplane-type connector) or barrier terminal strip (accepts AWG 14 to 30 wire sizes) Mounting Use the attached threaded standoffs or card-edge guides Notes: All values are nominal unless otherwise noted FSO (Full Scale Output) is the largest absolute value of the outputs measured at the range ends WIRING SCHEMATIC & LOOP RESISTANCE (LOAD) SENSOR SOLUTIONS /// LiM-420 Rev 6 07/2017 Page 2