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General 

OPERATING GUIDE

 

 

for use with 

 

PIEZOELECTRIC CHARGE MODE ACCELEROMETERS 

 

SPECIFICATION SHEET, INSTALLATION DRAWING 

AND CALIBRATION INFORMATION ENCLOSED 

 

PCB ASSUMES NO RESPONSIBILITY FOR DAMAGE CAUSED TO THIS PRODUCT AS A RESULT OF  

PROCEDURES THAT ARE INCONSISTENT WITH THIS OPERATING GUIDE. 

 
 

1.0 INTRODUCTION

 

Congratulations on the purchase of a quality PCB charge 
mode accelerometer.  In order to ensure the highest level 
of performance for this product, it is imperative that you 
properly  familiarize  yourself  with  the  correct  mounting 
and  installation  techniques  before attempting to operate 
this device.  If, after reading this manual, you have any 
additional  questions  concerning  this  sensor  or  its 
application,  feel  free  to  call  an  Application  Engineer  at 
716-684-0001 or the closest PCB representative. 
 

2.0 CHARGE MODE ACCELEROMETERS 

Ceramic  and  UHT  12  shear-structured  accelerometers 
offer  high  performance  for  precision  vibration 
measurements  in  high-temperature  environments.    The 
use  of  sensing  crystals,  operating  in  the  shear  mode, 
reduces  erroneous  output  due  to  base  strain,  thermal 
transients, and transverse motion. 
 
Charge mode accelerometers output a strong, high-
impedance charge signal directly from their sensing 
element.  They do not contain built-in signal 
conditioning electronics; the signal is conditioned 
externally by either a laboratory-style charge amplifier 
or in-line charge converter prior to being analyzed by a 
readout or recording device.  The absence of built-in 
electronics permits operation to elevated temperatures of 
500 °F (260 °C) for most ceramic crystal models and 

typically 900 

°

F

 

(482 °C) and extreme application up to 

100 °F (650 °

C) 

for

 

UHT-12.

 

 

These  accelerometers  are  ideal  for  structural  testing, 
machine  monitoring,  and  vehicular  shock  and  vibration 
measurement  tasks  where  high  temperatures  preclude 
the use of accelerometers with built-in microelectronics. 
 

Enclosed  is  a 

Specification  Sheet

,  which  lists  the 

complete  performance  characteristics  of  the  particular 
accelerometer. 
 

3.0 OPTIONAL FEATURES

 

In  addition  to  these  standard  features,  a  variety  of 
options are also available.  When listed before the model 
number,  the  following  prefix  letters  indicate  that  the 
sensor  is  manufactured  or  supplied  with  optional 
features: 

option-  adhesive  mount; 

J

  option-  electrical 

ground  isolation; 

M

  option-  metric  mounting  thread; 

option-  positive  polarity  output  (for  use  with  non-
inverting, signal conditioning amplifiers); and 

W

 option- 

water-resistant cable connection. 
 

4.0 INSTALLATION OVERVIEW 

When  choosing  a  mounting  method,  consider  closely 
both  the  advantages  and  disadvantages  of  each 
technique.    Characteristics  like  location,  ruggedness, 
amplitude 

range, 

accessibility, 

temperature, 

and 

portability  are  extremely  critical.    However,  the  most 
important  and  often  overlooked  consideration  is  the 
effect the mounting technique has on the high-frequency 
performance of the accelerometer. 
 
Shown  hereafter  are  six  possible  mounting  techniques 
and  their  effects  on  the  performance  of  a  typical 
piezoelectric  accelerometer.    (Note  that  not  all  of  the 
mounting methods may apply to your particular sensor.) 
The  mounting  configurations  and  corresponding  graph 
demonstrate  how  the  high-frequency  response  of  the 
accelerometer may be compromised as mass is added to 
the system and/or the mounting stiffness is reduced. 

 
Note:

  

The low-frequency response is unaffected by the 

mounting  technique.    Its  roll-off  behavior  is  dependent 

Summary of Contents for 357A08/NC

Page 1: ...ge output accel 0 3 pC g 10k Hz Installation and Operating Manual For assistance with the operation of this product contact PCB Piezotronics Inc Toll free 800 828 8840 24 hour SensorLine 716 684 0001...

Page 2: ...alized tests including sensitivity at elevated or cryogenic temperatures phase response extended high or low frequency response extended range leak testing hydrostatic pressure testing and others For...

Page 3: ...tion on particular operating steps The following symbols may be found on the equipment described in this manual This symbol on the unit indicates that high voltage may be present Use standard safety p...

Page 4: ...China RoHS 2 Disclosure Table Pb Hg Cd Cr VI PBB PBDE O O O O O O PCB X O O O O O O O O O O O X O O O O O O O O O O O O O O O O O O O O O O O O O X O O O O O O O O O X O O O O O O O O O O O X O O O O...

Page 5: ...O Wires O O O O O O Cables X O O O O O Plastic O O O O O O Solder X O O O O O Copper Alloy Brass X O O O O O This table is prepared in accordance with the provisions of SJ T 11364 O Indicates that sai...

Page 6: ...F 482 C and extreme application up to 100 F 650 C for UHT 12 These accelerometers are ideal for structural testing machine monitoring and vehicular shock and vibration measurement tasks where high tem...

Page 7: ...urface consider adhesive mounting as a possible alternative Inspect the area checking that there are no burrs or other foreign particles interfering with the contact surface STEP 2 Wipe clean the moun...

Page 8: ...or most applications It is generally used only for machinery monitoring and other portable trending applications Both the accuracy and repeatability at low 5 Hz and high frequency 1 kHz ranges are que...

Page 9: ...o a precise sensitivity such as 10 0 or 100 0 mV g for ease of data analysis This is accomplished with most PCB laboratory charge amplifiers and some miniature in line units as well For fixed sensitiv...

Page 10: ...dure themselves While this may result in both a savings of time and money it has also been attributed to incorrect readings and costly errors Therefore in an effort to prevent the common mistakes asso...

Page 11: ...Figure 12 Typical Calibration Set Up Adhesively mounted sensors use similar practices However in this case a small portion of quick bonding gel or similar temporary adhesive is used to attach the tes...

Page 12: ...s Incorrect Understand Back to Back Calibration limitations Do not expect the uncertainty of calibration to be any better than 2 In fact the uncertainty may be as high as 3 or 4 for frequencies 10 Hz...

Page 13: ...Jack 3 56 Coaxial Jack Electrical Connection Position Side Side 4 All specifications are at room temperature unless otherwise specified In the interest of constant product improvement we reserve the...

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