Outside views
5.9
1
2.5
3.8
7
6.7
7
10.1
M3 depth 2
Appr
o
x
.
8.1
unit: mm
***** is the serial number.
Typical response of the PV-91C
Frequency response
-40
-30
-20
-10
0
10
20
30
40
1
10
100
1000
10000
100000
Frequency [Hz]
R
e
lat
ive
ac
c
e
le
rat
io
n
le
ve
l
[d
B
]
:PV-91C+VP-53K (Screw)
[1 to 12000 Hz (
±
10%) at 23
°C
]
Base distortion sensitivity
Temperature characteristics of voltage sensitivity
Thermal transient response
-0.10
-0.08
-0.06
-0.04
-0.02
0.00
0.02
0.04
0.06
0.08
0.10
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Base
dist
or
tion
sensitivit
y
[(m/s
2
)/
str
a
in]
Time [s]
* PV-91C output per 1
strain when continuous and
quantitative strain is applied to mounting section
-20.0
-15.0
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
-50
0
50
100
150
Temperature [
°C
]
S
e
n
s
it
iv
it
y
te
m
p
e
ra
tu
re
c
o
e
ff
ic
ie
n
t
[%
]
-1.00
-0.80
-0.60
-0.40
-0.20
0.00
0.20
0.40
0.60
0.80
1.00
0
1
2
3
4
5
6
Ther
mal
tr
a
nsient
re
sponse
[(m/s
2
)/°
C
]
Time [s]
Thermal shock point
* PV-91C output per 1°C when a rapid fluctuation in
ambient temperature is applied to PV-91C
Explanation and notes about specifi cation items
Voltage sensitivity
The reference piezoelectric accelerometer PV-03 absolutely calibrated by ISO 5347
compliant laser interferometry is used for comparative calibration of the PV-91C.
The reference frequency for sensitivity calibration is 80 Hz.
Vibration frequency range
The frequency response of the PV-91C is measured through comparison to a ref-
erence accelerometer such as the PV-03. Frequency response is referenced to 80
Hz. The resonance frequency of the PV-91C is located at approximately 55 kHz.
The lower limit of the PV-91C's vibration frequency range is largely unaffected
by the mounting method.
Transverse response
This is the response of the accelerometer on an axis that is orthogonal to the sensitive
axis. It is largely due to material properties and slight angle shifts during assembly
of the accelerometer. If there is large vibration from a specifi c direction and vibra-
tions on an axis right angle to it are to be measured, the transverse response must
be taken into consideration.
Base distortion
When the mounting section of a piezoelectric accelerometer is subject to strain, noise
and sensitivity changes may occur. The accelerometer should therefore be mounted
on a sturdy and fl at surface that is not susceptible to distortion due to strain.
Thermal transient response
This refers to the change in output that occurs when the temperature of the acceler-
ometer changes. It is caused by the pyroelectric effect which produces an electrical
charge when temperature fl uctuates, and by stresses exerted on the piezoelectric
element due to structural thermal expansion. Thermal transient response normally
occurs when the temperature of the vibrating object to which the accelerometer is
mounted changes, but it can also arise due to changes in the ambient temperature.
If the air in the measurement location is subject to temperature changes, the effect
can be reduced by providing a cover or similar for the accelerometer.
Specifi cations
Standard compliance EU RoHS Directive, China RoHS, WEEE Directive
CE mark
(EMC Directive: 2004/108/EC
EN 61326-1: 2006/IEC 61326-1: 2005)
*When combined with supplied VP-51LC
Method
Piezoelectric accelerometer detection, annular shear mode
Axis
1 axis (perpendicular to mounting surface)
Voltage sensitivity
1 mV/(m/s
2
) (at 80 Hz, 23°C)
DC bias voltage
7 V to 15 V DC (all temperature range)
(approx. 12.5 V at 23°C )
Residual noise
20 µVrms (TYP.), 40 µVrms (MAX.) (1 Hz to 20 kHz, 23°C)
Vibration frequency range
1 Hz to 20 kHz (±10%) at -50°C to 150°C
1 Hz to 2 Hz (±15%), 2 Hz to 20 kHz (±10%) at 150°C
to 170°C
Output resistance
100 Ω or less
Maximum measurable acceleration
5000 m/s
2
(peak)
Differ according to temperature, voltage sensitivity and
supply voltage
Transverse response
5% or less (30 Hz)
Base distortion sensitivity
0.006 (m/s
2
)/µstrain (TYP.), 0.02 (m/s
2
)/µstrain (MAX.)
(using 3 Hz high-pass fi lter)
Thermal transient response
0.04 (m/s
2
)/°C (TYP.), 0.1 (m/s
2
)/°C (MAX.)
(using 3 Hz high-pass fi lter)
Supply voltage
18 V to 30 V DC (constant current 2 to 4 mA)
Rated voltage 24 V
Polarity
Acceleration in the direction from the mounting surface to
the accelerometer generates positive output voltage
Grounding Non-insulated
Mounting
Screw mounting, M3 screw
Case material
Titanium alloy
Connection cable
VP-51L, VP-51LB, VP-51LC
Conform to CE marking only when combined with VP-51LC
Operating temperature range
-50°C to +170°C
Storage temperature range
-50°C to +170°C
Waterproofi ng
Non-waterproof (unit must be protected from condensation
and corrosive gases during storage and measurement)
Dimensions
7 mm (hex width across fl ats) × 12.5 mm (H)
(excluding connector)
Mass
Approx. 1.8 g
Supplied accessories
Case
1
Cable with 10-32 UNF connectors and ferrite cores
VP-51LC
1
M3 screw
VP-53K
2
Insulation attachment
VP-53W
1
Spanner (for 7 mm)
1
HEX wrench
1
Calibration chart
1
Instruction manual
1
Inspection certifi cate
1
Optional accessories
BNC adapter
VP-52C
Accelerometer cable
VP-51L
Low-noise coaxial cable (heat-resistant)
VP-51LB
No. 56950
12-03