Charge/IEPE Amplifier for Rotating Machinery

Dual vibration amplifier specially designed for the high demands of testing rotating machinery

The 28302B is a dual channel card designed to condition vibration signals from rotating machinery. The card accepts inputs from single-ended or differential piezoelectric accelerometers, IEPE accelerometers, or remote velocity sensors. AC outputs are provided for acceleration, velocity and displacement. A DC output for acceleration, velocity or displacement is also provided. A fully programmable 12-pole band-pass filter is provided to eliminate unwanted noise.

Overall noise of charge amplifiers is heavily influenced by input impedance characteristics of the accelerometer and input cabling. The 28302B input stage was designed to minimize these effects while still maintaining an operating bandwidth of 0.3 Hz to 20 kHz. The charge amplifier design is free from peaking when used with high temperature piezoelectric sensors.

The 28302B is a member of the Precision 28000 family of signal conditioners.

The 28000 Signal Conditioning System

Learn more about the 28000 Signal Conditioning System >

  • The 28302B Dual-Vibration Amplifier

    The 28302B designed for Testing Rotating Machinery

    MEASUREMENTS:

    • Rotating Machinery
    • Load Measurements
    • Torque Measurements
    • Dynamic Force Measurements
    • Dynamic Pressure Measurements
    • Shock Measurements
    • Vibration Measurements
    • Acoustic Measurements

28302B Dual-Vibration Amplifier Features:

  • Two channels per card: 32 channels per 28016 chassis
  • Isolated or grounded single-ended Piezoelectric input
  • Balanced differential Piezoelectric input
  • IEPE input with IEPE power
  • Remote charge converter (RCC) input w/IEPE power
  • Remote velocity sensor input
  • Five filtered AC outputs: two acceleration, two velocity and one displacement
  • One DC output: acceleration, velocity or displacement
  • Programmable alarm level with relay contact output measures acceleration, velocity or displacement levels
  • Internal shunt calibration capacitors with 0.1% accuracy
  • Three overload detectors: Charge Converter, Pre-Filter and Displacement Out
  • Channel Mute function places channel in low noise state if an accelerometer fails during a test run

View the 28302B 2-Channel Dual Vibration Amplifier Specification Sheet >

Charge and IEPE Conditioner Comparison Guide

Card 28304 28324 28316C 28302B
Type Single Ended Charge,
IEPE (GND or ISO)
with Long Distance TED
Single Ended Charge,
IEPE (GND or ISO)
with Long Distance TEDS
IEPE (GND or ISO)
with Long Distance TEDS
Single Ended or
Differential Charge, IEPE or Velocity Coil Input
Channels/Card 4 4 16 2
Channels/System 64 64 256 32
Applicable Transducer Piezoelectric or IEPE Sensor, Remote Charge Converter, AC Voltage Piezoelectric or IEPE Sensor, Remote Charge Converter, AC Voltage IEPE Sensor with TEDS (Optional) and AC Voltage Piezoelectric or IEPE Sensor, Velocity Coil, AC Voltage
Interface 2-Wire Coaxial on Combo-D 2-Wire Coaxial on Combo-D 2-Wire with Shield 2 Wire Coaxial or 3-Wire LEMO
Excitation IEPE Current, 0, 4, 8, 12 mA IEPE Current, 0, 4, 8, 12 mA IEPE Current: 0, 2, 4 or 8 mA IEPE Current: 8.5 mA
Bandwidth 0.25 Hz to 450 kHz 0.5 Hz to 170 kHz 0.25 Hz to 140 kHz 0.3 Hz to 20 kHz
Gain x1/16 to x8192 with
0.05% Resolution
x1/16 to x1024 with 0.05% Resolution x1 to x512 with
0.1% Resolution
PE: 1 to 200 pC/g
IEPE: 0.1 to 200 mV/g
Filter 4, 8 Poles; FLAT/PULSE Low-Pass or Band Pass 4-Poles; FLAT/PULSE
Low-Pass
4-Poles; Time Delay or Butterworth 6-Pole HP, 6-Pole Low-Pass
Cut Off Frequencies FLAT: 2 Hz to 204.6 kHz PULSE: 1 Hz to 102.3 kHz FX02: 300, 1k, 3k,
10k, 30 kHz*
FX02: 300, 1k, 3k,
10k, 30 kHz*
HP: 0.3, 3, 10, 30, 100
LP: 50 Hz to 12.75 kHz in
50 Hz steps
PULSE: 1 HZ to102.3 kHz
Outputs (2) Buffered Single-Ended Outputs per Channel (2) Buffered Single-Ended Outputs per Channel (2) Buffered Single-ended Outputs per Channel (2) Accel, (2) Velocity,
(1) Displacement, (1) DC,
(1) Alarm
* Custom cutoff frequencies are available. Please consult factory.