PA2001 Pre-Amplifier

The Motion Sensors (MSI) PA2001 series preamplifiers allow convenient interfacing with process measuring devices and digital electronics.

This series of preamplifiers/signal conditioners is available in a combination version that provides user selection of either VR or RF sensor input.

When used with VR sensors they will accept low-level signals and provide hysteresis to eliminate unwanted noise and interference. Operating range is 4 to 10,000 Hz. When used with RF sensors, they provide false pulsing safeguards, air gaps up to 0.150", a frequency range of 2 to 5,000 Hz, as well as a precisely tuned carrier signal to allow for maximum signal reliability.

Installation Drawing

Input Power

  • Voltage: 8 to 30 VDC
  • Current draw: 25 mA @ 24 VDC
  • Reverse polarity protected

RF Sensor Input

  • Modulation carrier frequency: 25 KHz
  • Input frequency: 2 Hz to 5 KHz
  • Maximum air gap: 0.150"
  • Preferred coil inductance: 1.0 mH +/- 10%
  • Max. distance from sensor to preamp: 100'

VR Sensor Input

  • Input protected, RF and band pass filtered
  • Input frequency: 0 to 10 KHz
  • Trigger sensitivity: 4 mV RMS min (note: at 4 mV frequency range 10 Hz to 3 KHz)
  • Input impedance: 40K ohms (nominal)
  • Max. input signal: 600 V RMS
  • Max. distance from sensor to preamp: 100'

Pulse Output Options

  • All output options are user selectable
  • Open Collector; Vmos transistor maximum OFF state voltage 30 VDC; maximum ON current 400 mA
  • TTL/CMOS fanout of 5 TTL/CMOS loads
  • 0 to 10 VDC square wave
  • Square wave tied to input voltage

Temperature Range

  • Operating: -40°F to +185°F
    (-40°C to +85°C)
    Units to +125°C also available.
  • Storage: -40°F to +302°F
    (-40°C to +150°C)


  • Unit is intended for mounting in an elbow conduit box suchas Crouse-Hinds Model LBY15.
  • Optional explosion proof box available upon request
  • Enclosure requirements: GUAx16,26,36 or equivalent


  • CE compliant to EMC Directive 2004/108/EC for use in residential, commercial, light industrial and heavy industrial environments


  • Unconditional one (1) year warranty if used within specifications

Physical Dimensions

  • Board diameter: 1.1" +/- 0.1"
  • Height: 0.96" +/- 0.02"
ATEX & IECEx Certified: Custom & Standard Speed Sensors for Intrinsically Safe applications (also approved by CSA w/NRTL/C)