Measurement Computing 4623 User manual

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 1 of 8 t&[e-mail]
TMTM
Model 4623 Accelerometer
Measurement Specialties, Inc.
Vibration Sensors Design Center
32 Journey, Suite 150
Aliso Viejo, CA 92656 USA
Tel: [phone]
www.meas-spec.com
[e-mail]

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 2 of 8 t&[e-mail]
TMTM
Warranty
Measurement Specialties, Inc. accelerometers
are warranted during a period of one year from
date of shipment to original purchaser to be free
from defects in material and workmanship. The
liability of Seller under this warranty is limited to
replacing or repairing any instrument or
component thereof which is returned by Buyer,
at his expense, during such period and which
has not been subjected to misuse, neglect,
improper installation, repair, alteration, or
accident. Seller shall have the right to final
determination as to the existence and cause of a
defect. In no event shall Seller be liable for
collateral or consequential damages. This
warrant is in lieu of any other warranty,
expressed, implied, or statutory; and no
agreement extending or modifying it will be
binding upon Seller unless in writing and signed
by a duly authorized officer.
Receiving Inspection
Every Measurement Specialties, Inc.
accelerometer is carefully inspected and is in
perfect working condition at the time of
shipment. Each accelerometer should be
checked as soon as it is received. If the unit is
damaged in any way, or fails to operate, a claim
should immediately be filed with the
transportation company.
Service Concerns
If a Measurement Specialties, Inc. instrument
requires service, first contact the nearest
Measurement Specialties, Inc. representative.
They may be able to solve the problem without
returning the unit to the factory. If it is
determined that factory service is required, call
Customer Service at the regional headquarters
for an RMA number before return.
Returns
All units being returned to the factory require an
RMA (Return Material Authorization) number
before they will be accepted. This number may
be obtained by calling Customer Service at the
regional headquarters with the following
information; model number(s), quantity, serial
number(s), and symptoms of the problem, if
being returned for service. You must include the
original purchase order number if under
warranty.
Recalibration Services
The Vibration Sensors Design Center and its
two manufacturing facilities in China and France
offer factory re-calibration services for
Piezoresistive, Piezoelectric and Integrated
Electronics Piezoelectric (IEPE, ISOTRON, ICP,
etc.) accelerometers. NIST (US), DKD
(Germany), COFRAC (France) traceable
calibration services on sensitivity at 100 Hz (102
or 120 Hz in Europe) and full frequency sweeps
are offered. Contact the regional headquarters
for pricing information.
Inquiries
Address all inquiries on operation or applications
to your nearest Sales Representative, or to the
Vibration Applications Support as follows:
Global Headquarters
1000 Lucas Way
Hampton, VA 23666, USA
Tel: [phone]
Vibration Sensors Design Center
32 Journey, Suite 150
Aliso Viejo, CA 92656, USA
Tel: [phone]
European Headquarters
Impasse Jeanne BENOZZI
CS 83 163, 31027 Toulouse Cedex 3, France
Tel: [phone]
Asian Headquarters
Measurement Specialties (China), Ltd.
No. 26 Langshan Road
Shenzhen High-Tech Park (North)
Nanshan District, Shenzhen 518057, China
Tel: [phone]

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 3 of 8 t&[e-mail]
TMTM
Description
The Model 4623 is a signal conditioned and temperature compensated MEMS accelerometer offering
high sensitivity in ranges from ±2g to ±100g. The DC response accelerometer offers outstanding
performance over a wide operating temperature range and incorporates an EMI/EMC protection circuitry
for harsh installations. The output is filtered and signal conditioned to provide a low noise amplified signal
with exceptional resolution. The Model 4623 accelerometer incorporates a rugged strain relief for
demanding applications and is packaged in an anodized aluminum housing.
Installation
The model 4623 accelerometer is designed to be screw mounted but can also be adhesively mounted if
the installation does not allow for screw mounting.
Screw Mounting
For screw mounting of accelerometers the following guidelines should be followed:
The mounting surface should be clean and free of any residue or foreign material.
The mounting surface should be smooth, flat, and with a maximum surface roughness of 32 micro-
inches rms.
Optional: Apply a light coating of coupling fluid (machine oil or silicone grease) on the mating surface
to maximize the usable frequency range.
Torque screws to recommended limits using steel washers under the heads of the mounting screws.
Use manual torque wrench (do not use electric tools).
Mounting screws
Torque to 3 lb-in (0.3 Nm)

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 4 of 8 t&[e-mail]
TMTM
Adhesive Mounting
To avoid damaging the accelerometer during subsequent removal, it is recommended to use an
adhesive mounting adaptor for this method of attachment. For adhesively mounting of accelerometers
the following guidelines should be followed:
The mounting surface should be clean and free of any residue or foreign material.
The mounting surface should be smooth, flat, and with a maximum surface roughness of 64 micro-
inches rms.
For best high frequency performance a cyanoacrylate adhesive is recommend. A thin layer offers
best frequency response.
Soften adhesive cured adhesive with a chemical debonder (eg. acetone) prior to removal. Gently
shear accelerometer loose from the mounting surface after waiting a few minutes for the debonding
agent to penetrate the epoxy. Make sure not to use excessive force as this may damage the
accelerometer.
Biaxial Mounting Configurations
The model 4623 accelerometer has a unique housing that enables it to be mounted in two different
orientations to measure either the normal or transverse acceleration input. By simply rotating the housing
90 degrees, the accelerometer can now be used to measure transverse motion. The two mounting
orientations are illustrated below.

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 5 of 8 t&[e-mail]
TMTM
Wiring
The accelerometer is designed to be operated from 7-30Vdc excitation and provide a ±2V full scale
output with a 2.5V reference voltage. The output is DC-coupled and can be used in either single-ended
or differential mode. Differential mode offers the best performance since common mode errors are
minimized. The electrical hookup for both modes of operation is detailed below.
Single-Ended Operation
For single-ended operation a 2.5Vdc bias will be present on the output leads and the output of the
accelerometer will be 0.5-4.5V full scale. For single-ended operation the accelerometer should be
connected to the signal conditioner as detailed below. To avoid permanently damaging the
accelerometer, the white wire should not be connected to ground.
SINGLE ENDED OUTPUT
Differential Operation
For differential operation the output of the accelerometer will be ±2V full scale without a bias voltage
present. For differential operation the accelerometer should be connected to the signal conditioner as
detailed below. Common mode voltage is 2.5V.
DIFFERENTIAL OUTPUT

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 6 of 8 t&[e-mail]
TMTM
Cable Routing
The model 4623 accelerometer incorporates a FEP jacketed cable with an integral shield. The cable
assembly should be properly secured at regular intervals during testing. It is recommended to use
clamps, wax, or tape to secure the cable to minimize cable motion that can add noise to the output
signal. The initial attachment should be within two to three inches of the accelerometer with some slack
in the cable to prevent tension at the connector joint
Avoid routing cables near high-voltage wires and also ground the shield at the signal conditioner to
minimize ground loops.

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 7 of 8 t&[e-mail]
TMTM
Noise Floor Specifications
The model 4623 accelerometer incorporates a LP filtered output for a high output signal. The noise
specifications for this accelerometer are detailed in table below.
FULL SCALE
RATING
(g-pk)
SENSITIVITY
(mV/g)
±5% AMPL
PASSBAND
(Hz)
PASSBAND
NOISE
(µVrms)
SPECTRAL
NOISE
(µg-rms/√Hz)
DYNAMIC
RANGE
(dB)
2
1000
150
500
35
72
5
400
150
500
38
76
10
200
200
450
75
76
25
80
400
550
219
75
50
40
600
450
316
74
100
20
1000
450
516
74

Operating Manual
Measurement Specialties, Inc. www.meas-spec.com [phone]
32 Journey, Suite 150, Aliso Viejo, CA 92656 USA 8 of 8 t&[e-mail]
TMTM
Frequency Response & Phase Deviation Curves
The typical frequency response and phase deviation curves for the model 4623 accelerometer are
illustrated below.
Typical Phase Response
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
35
40
10 100 1000 10000
Frequency (Hz)
Phase (degrees)
2g Range
10g Range
30g Range
50g Range
100g Range
200g Range
Typical Frequency Response
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
35
40
110 100 1000 10000
Frequency (Hz)
Sensitivity Deviation (%)
2g Range
5g Range
10g Range
25g Range
50g Range
100g-500g Range