Confirm sensor excitation
IEPE accelerometers require constant-current power through the signal cable. The acquisition input must provide the correct current and compliance voltage while allowing the dynamic signal to return on the same conductor.
- Check required excitation current
- Confirm compliance voltage and sensor bias
- Verify input coupling and settling time
- Record sensor sensitivity and serial number
Match sensitivity and input range
Sensor sensitivity and expected acceleration determine the voltage presented to the DAQ. Too little range clips the signal; too much range wastes useful resolution.
- Estimate normal and maximum acceleration
- Convert acceleration to expected voltage
- Allow transient headroom
- Check overload recovery
Select bandwidth and sample rate
Sampling should cover the highest useful vibration frequency with suitable anti-alias filtering. Maximum sample rate is not automatically the correct setting.
- Define the useful frequency band
- Review sensor resonance and mounted response
- Confirm anti-alias filter behaviour
- Choose record length from FFT resolution
Control mounting and cabling
Mounting stiffness, cable motion and grounding can change the measured signal. Repeatable installation is essential for comparison and trend.
- Use an appropriate mounting method
- Secure cable near the sensor
- Avoid sharp cable bends and rubbing
- Document location and direction
Preserve calibration metadata
The software should store sensitivity, unit, channel, point, direction and acquisition settings with the record.
- Sensor sensitivity
- Engineering unit
- Sampling and filter settings
- Machine and point identification