vibration testing
• Shock calibration
• Resonance
• Dynamic pressure
A range of shaker options bring you a
wide scope of capabilities. Each system
provides all the necessary components ‘outof
the-box’ – from the data acquisition
hardware to the Windows PC controller.
Cost reducing automation is built in via
easy-to-use Windows software, offering a
streamlined approach to calibration
procedures, as test parameters are stored
and recalled automatically for each
accelerometer. This makes for ‘hands-off’
operation once the sensor is mounted.
After this point, calibrations are typically
performed in a minute per axis – a
substantial time savings over older, more
traditional systems.
RESPOND TO UNEXPECTED
TEST DATA
In your testing career, have you ever
encountered unexpected or unreliable test
data? After acquiring unexpected test
results, a question is typically asked (even
if it is unsaid) that seems to have a binary
set of answers. Something went ‘wrong’ -
was it the test article or was it the test?
What can you trust? This immediately
leads to scrutiny of the testing process, and
undoubtedly, instrumentation calibration
is on that checklist of scrutiny. In these
situations, time and money are saved with
a confident and certain response. For
calibration, confidence is born from
adherence to international standards,
repeatable and reliable calibration
processes, as well as quick and reliable
access to the data or documentation
(usually realized with a robust calibration
database). A response that combines these
things quickly “checks the box” for the
calibration question.
Performing regular recalibrations can
help you to avoid a time- and laborintensive
review. With an in-house
calibration system, you have the ability to
control your calibration process from start
to finish. Perhaps you have a critical test
to perform on a satellite prior to launch. In
this case, you may want to calibrate both
before and after your test to ensure the
accuracy of your invaluable data set.
Perhaps you’ve taken data that will be used
in legal proceedings where the
measurement must be correct rather than
with your current strategy is key to
evaluating and developing a plan that best
suits your interests. As a team of test and
measurement experts, we understand the
inherent frustrations of a test that results
in unexpected or unreliable data, a sensor
that has passed its calibration date, or –
worse yet – realizing necessary sensors are
out for calibration. We also understand the
uncertainty and questions that arise with
unexpected test results and out of spec
sensors. Calibrating in house, on your own
system allows you to proactively address
each of these issues. The 9155 Calibration
Workstation from The Modal Shop offers
precise, efficient, automated accelerometer
calibration, bringing control and
confidence to your process.
We’ve often thought, shouldn’t accurate
calibration be like flipping a light switch?
When you get home from a long day at the
office, you step in the door and flick the
lights on. Instantly, everything is
illuminated. You don’t need to think about
how the electricity is routed to your home,
how the power plant utilizes their
technology, or how they could improve
their processes. All you need to do is flip
the switch. We feel the same way about
delivering a calibration solution to you.
With a system from The Modal Shop, over
20 years of proven (and then improved)
products and processes offer you a solution
used by companies around the globe. All
you need to do is mount your sensor and
start calibrating. In approximately a
minute per axis, you’ll have calibrated your
sensor, providing the data to ensure your
next measurements. We take care of your
instrumentation while you focus on your
own product development.
REDUCING COST
The Accelerometer Calibration
Workstation Model 9155 delivers accurate
back-to-back comparison calibration of ICP
(IEPE), charge mode, and piezoelectric
accelerometers in accordance with ISO
16063-21: 2003. Options to calibrate
piezoresistive, capacitive, velocity, 4-20 mA,
visual output (meters), and dynamic
pressure sensors - as well as instrumented
force hammers - are also available. A host
of configurations include:
• Automated TEDS sensor updating
• Linearity check
• Low frequency calibration down to 0.1 Hz
AEROSPACETESTINGINTERNATIONAL.COM // SHOWCASE 2020 61
The ground vibration portion of the
testing can use up to several hundred
ICP accelerometers for modal analysis
response measurements. Managing the
accuracy of this accelerometer inventory is
an important job, often leading the
vibration test technician to ask, ‘How often
should I recalibrate my accelerometers?’
The cost of recalibration is relatively low
for an aerospace organization that invests
in an automated calibration system. These
systems can perform a globally
standardized calibration in less than 60
seconds per axis, apply pass and fail
criteria, automatically store the data, and
generate a calibration certificate.
Aerospace organizations that perform 60
or more calibrations per year frequently
justify the investment in a calibration
system. Those with fewer can acquire
outsourced services from an accredited
laboratory, like PCB Piezotronics. In either
case, the cost for doing so is justified by the
risk of not doing so.
A few examples should help to show the
importance of calibration. First, the
organization can mitigate the risk of not
knowing if an accelerometer is good, for
example after dropping it. Next, the
vibration test results could be called into
question if the instrumentation was not
recalibrated within the last 12 months, or
some other organizationally mandated
time limit. This may force the ground
vibration test team to perform the modal
analysis test campaign again. Finally, if the
particular test has a shock event or
temperature extremes involved, the
sensors can be recalibrated after the test to
see if anything has changed.
PRECISION VIBRATION AND
PRESSURE CALIBRATION SYSTEMS
Calibration solutions from The Modal
Shop, sensor manufacturer PCB
Piezotronics’ sister company, allow you to
perform accurate transducer calibrations,
ensuring the quality of your measurement
data the first time. We are dedicated to the
metrology community and committed to
delivering quality, performance, and
reliability in calibration.
WHAT DO YOU DO FOR
CALIBRATION?
Are you calibrating after each test,
annually, or less frequently? Familiarity
2
1 // Calibrating in house, on
your own system allows
you to proactively address
each of these issues
2 // An efficient calibration
process
/AEROSPACETESTINGINTERNATIONAL.COM