Accelerometer & DAQ Selection 101

What you'll leave knowing

Outcomes for this primer.

Short, interactive and self-paced. Every idea is shown with a live instrument, then checked in the exam.

Walk the full measurement chain — transducer → cable → conditioner → DAQ.

Pick the right accelerometer type and read the datasheet numbers that matter.

Understand how mounting sets the highest frequency you can trust.

Avoid ground loops, inter-channel skew and calibration drift.

The curriculum

34 lessons, in order.

Each lesson is one focused screen — a concept, an interactive graphic, and a plain-language read. Climb the chain, then sit the exam.

Reading the graphs

Time on top, FFT below — reading order and the noise floor.

The measurement chain

Five links: transducer → cable → conditioner → DAQ → software.

Inside the sensor

An accelerometer is a mass on a crystal that feels acceleration.

Which motion, which sensor

Displacement, velocity, acceleration — three views of one shake.

The first datasheet number

Sensitivity (mV/g): loud and sensitive, but easier to overload.

Accelerometer type 1 of 5

IEPE / ICP — the everyday sensor with electronics built in.

Accelerometer type 2 of 5

Charge-mode — the raw crystal for very hot places.

Accelerometer type 3 of 5

Piezoresistive — measures down to DC and steady g.

Accelerometer type 4 of 5

Capacitive / MEMS — tiny, cheap, embeddable, also DC-capable.

Accelerometer type 5 of 5

Loop-powered 4–20 mA transmitter — install-and-forget protection.

Beyond acceleration · 1 of 5

Tachometer / phase reference — the once-per-rev heartbeat.

Beyond acceleration · 2 of 5

Proximity / eddy-current probe — watching the shaft itself.

Beyond acceleration · 3 of 5

Force sensor & impact hammer — the controlled tap for modal work.

Beyond acceleration · 4 of 5

Impedance head — force and acceleration at the very same point.

Beyond acceleration · 5 of 5

Shaker / modal exciter — dialling in a known input.

Datasheet parameter · the big one

Frequency response, the −3 dB point, and mounted resonance.

The error hiding in plain sight

Mounting sets the wall — a magnet can erase your fault.

Datasheet parameter

Dynamic range — seeing a whisper next to a shout.

Datasheet parameter

Noise floor (µg/√Hz) — the sensor's own hiss sets the smallest fault.

Datasheet parameter

Transverse sensitivity — cross-axis leakage between directions.

Datasheet parameter

Amplitude linearity — does output stay proportional to input?

Datasheet parameter

Phase response — timing must survive the sensor too.

Datasheet parameter

Temperature range & coefficient — heat shifts the numbers.

Datasheet parameter

Settling time & bias — why IEPE needs a few seconds.

Datasheet parameter

IEPE excitation — the constant current that powers the sensor.

Datasheet parameter

Grounding & case isolation — killing the ground loop.

Datasheet parameter

TEDS — the sensor that introduces itself.

Error mechanism · the DAQ

Sample rate, Nyquist & aliasing — fast enough, or a false peak.

Error mechanism · the DAQ

Inter-channel skew — why multiplexed DAQs lie about phase.

The conditioning half

Signal conditioners — the constant-current source in the middle.

Read the real datasheet

The PhonoVibe DAQ family — D, Q, O and HD.

Trust the numbers

Calibration — verify the sensitivity is still true.

Put it together

Choose the transducer + mount + conditioning + DAQ for THIS job.

Recap

Everything you need to choose well, in one place.

Finish all 34 lessons and pass the 25-question exam to earn your completion certificate — issued on the spot.

Accelerometer & DAQ Selection 101

Outcomes for this primer.

34 lessons, in order.

Part of the Vibration Foundations badge.

Vibration Foundations

A primer — not ISO 18436 certification