Vernier 3D-BTA Quick Start Manual

3-Axis
Accelerometer
(Order Code 3D-BTA)
The 3-Axis Accelerometer consists of
three –5 to +5 g accelerometers mounted
in one small block. Using the
appropriate data-collection hardware and
software, you can graph any of these components, or calculate the magnitude of
the net acceleration. The 3-Axis Accelerometer can be used for a wide variety of
experiments and demonstrations, both inside and outside the lab.
Note: Vernier products are designed for educational use. Our products are not
designed nor are they recommended for any industrial, medical, or commercial
process such as life support, patient diagnosis, control of a manufacturing
process, or industrial testing of any kind.

What's Included

3-Axis Accelerometer

l

Compatible Software and Interfaces

See
www.vernier.com/manual/3d-bta
compatible with the 3-Axis Accelerometer.

Getting Started

1. Connect the sensor to the interface (LabQuest Mini, LabQuest 2, etc.).
2. Start the appropriate data-collection software (Logger Pro, Logger Lite,
LabQuest App) if not already running, and choose New from File menu.
The software will identify the sensor and load a default data-collection setup.
You are now ready to continue your experiment.
If you are collecting data using a Chromebook™, mobile device such as iPad
or Android™ tablet, or a Vernier wireless sensor or interface, please see the
following link for up-to-date connection information:
www.vernier.com/start/3d-bta

Using the Product

Connect the sensor following the steps in the Getting Started section of this user
manual.

Calibration

You should not need to calibrate this sensor. Each sensor is calibrated prior to
being shipped to you. In most experiments you can simply use the default
calibration, then use the software's zeroing option to zero the sensor along the
axes.
for a list of interfaces and software
Calibration may be done using the acceleration due to gravity. To calibrate the
sensor for measuring acceleration in the horizontal direction:
1. Position the accelerometer with the arrow pointing down for the first
calibration point.
2. Define this as –9.8 m/s
3. Rotate the accelerometer so the arrow points up and use the reading for the
second calibration point.
4. Define this as +9.8 m/s
acceleration when held horizontally.
5. Repeat this procedure for each axis.
If you want to calibrate for measuring acceleration in the vertical direction,
follow the procedure above, but define the first calibration point as 0 g or 0
2
m/s and the second point as 2 g or 19.6 m/s
not really that different, in both cases there is a 19.6 m/s
acceleration between the two calibration points.

Specifications

Power
For each axis
Stored calibration information

How the Sensor Works

Since the accelerometer is sensitive to both acceleration and the Earth's
gravitational field, interpreting accelerometer measurements is complex. A useful
model for understanding accelerometer measurements is a spring-based scale
®
with a reference mass (or object) attached to the scale. If the scale is pointing
upward (the usual orientation for such a device) the weight of the mass causes
the spring to compress, and you get a non-zero reading. If you were to turn the
scale upside down, the spring will be extended, instead of compressed, and we
get a reading of the opposite sign. If you turn the scale so it points sideways,
and keep it motionless, then the spring will just be at its relaxed length, and the
reading will be zero. If you accelerated the scale toward the mass, then the
spring would compress; away, and the spring would stretch.
In each case the scale is reading a value corresponding to the normal force on
the mass. This reading can be made relative by dividing out the mass, giving
units of N/kg, which is the same as m/s
interpreted in exactly this way.
1
2
or –1 g.
2
or +1 g. The accelerometer will then read 0 with no
2
. Note: The two calibrations are
2
difference in
30 mA @ 5 VDC
2
Range: ±49 m/s (±5 g)
2
Accuracy: ±0.5 m/s (±0.05 g)
Frequency Response: 0–100 Hz
2
Slope: 30.46 m/s /V
2
Intercept: –72.62 m/s
2
. Accelerometer measurements can be