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4.2-1 ADHESIVE MOUNT REMOVAL 

(other than wax) 

 

Caution:

  It  is  usually  difficult  or  near  impossible  to 

remove  a  direct  adhesive  mounted  high  sensitivity  DC 
transducer without damaging it. That is, adhesive mounted 
with  cyanoacrylate  or  epoxy,  without  use  of  an 
intermediary mounting base. However, adhesive mounting 
is  often  used  for  temporary  installation  or  when  the  test 
object  surface  cannot  be  adequately  prepared  for  screw 
mounting.

 

 
NOTE:    
A  chemical  debonder  should  always  be  used  to 
avoid  sensor  damage.  Care  should be exercised to avoid 
excessive  force  being  applied  to  case  body  during 
removal. 
 

To avoid damaging the accelerometer, a de-bonding agent 
must  be  applied  to  the  adhesive  prior  to  sensor  removal.  
With  so  many  adhesives  in  use  (everything  from  super 
glues,  dental  cement,  epoxies,  etc),  there  is  no  universal 
de-bonding agent available.  The de-bonder for the Loctite 
454 adhesive that PCB offers is Acetone.  If you are using 
anything  other  than  Loctite  454,  you  will  have  to  check 
with  the  individual  manufacturers  for  their  de-bonding 
recommendations.  The de-bonding agent must be allowed 
to penetrate the surface in order to properly react with the 
adhesive,  so  it  is  advisable  to  wait  a  few  minutes  before 
removing the sensor. 
 
After the de-bonding agent has softened the adhesive, use 
a  gentle  shearing  (or  twisting)  motion  (by  hand  only)  to 
remove the sensor from the test structure. 
 

 
5.0 CABLING 
 
5.1 Units with integral connectors 
 

Care  and  attention  to  cable  installation  and  cable 
condition is essential as the reliability and accuracy of any 
measurement  system  is  no  better  than  that  of  its  weakest 
link.    Due  to  the  nature  of  vibration  and  shock 
measurements,  all  sensor  cables  will  ultimately  fatigue 
and fail.  Good installation practice will extend the life of 
a cable, however, it is highly recommended to keep spare 
cables  on  hand  to  enable  continuation  of  the  test  in  the 
event of a cable failure. 
 

STEP 1: 

Ascertain that you have the correct cable type. 

 
Note:  Most  high  sensitivity  DC  accelerometers  have 
integral cable connections; therefore the cable leads at the 
opposite  end  from  the  accelerometer  are  the  main  focus 
and  will  apply  to  the  specific  connector  plugs  associated 
with follow-on electronics/signal conditioning equipment. 
 

One  cable  type  cannot  satisfy  all  applications.  Industrial 
applications  often  require  shielded,  twisted-pair  cables  to 
reduce  the  effects  of  EMI  and  RFI  that  is  present  near 
electrical motors and machinery.  Teflon-jacketed cabling 
may  be  necessary  to  withstand  corrosive  environments 
and  higher  temperatures.    Feel  free  to  contact  a  factory 
representative  for  a  specific  recommendation  on  cables 
that are best suited for your application. 
 

STEP 2: 

Connect the cable to the accelerometer. 

 
A  small  amount  of  thread-locking  compound  placed  on 
the connector threads prior to attachment helps secure the 
cable  during  testing.    In  wet,  oily,  or  dirty  environments, 
the connection can be sealed with silicone rubber sealant, 
O-rings, and flexible, heat-shrink tubing. 
 

Multi-Conductor  Cables:

  Make  accelerometer        cable 

connection to appropriate connector plug via soldering or 
crimping  leads  to  plug  sockets.  Specific  instructions  for 
this  activity  are  completely  dependant  on  the  plug 
required  (D-sub,  circular,  Lemo,  Fischer,  etc.)  to  mate  to 
follow-on  conditioning  equipment’s  input  receptacle. 
Refer  to  instrumentation  interface  guidelines  for  proper 
mating of accelerometer cabling. 
 

Pigtail  Connections: 

Certain  high  sensitivity  DC 

accelerometers  are  provided  with  lightweight  cables 
having  “Pigtail”  connections.    This  type  of  connection 
reduces  overall  weight  and  incidence  of  connection 
intermittency  under  shock  conditions.    In  the  event  of  a 
cable or connection failure, the cables may be repaired in 
the  field  simply  by  re-soldering  the  stripped  leads  to  the 
exposed  pins  on  the  sensor.    (Check  the 

Installation 

Drawing

 to determine pin functions).  In many cases, it is 

also  helpful  to  protect  the  solder  joint  with  heat-shrink 
tubing  or  epoxy.  It  should  be  noted that cable breaks too 
close to the accelerometer case, may not be repairable due 
to insufficient cable material for repair.  
 

NOTE: If you do not have the experience or resources to 
attach  pigtail  leads,  consult  PCB  to  discuss  factory 
attachment.    Damage  to  internal  electronics  may  be 
caused  by  excessive  heat  during  soldering  and  such 
failure is not covered by warranty. 
 
STEP 3: 

Route the cable to the signal conditioner, making 

certain  to  relieve  stress  on  the  sensor/cable  connection.  
Also,  minimize  cable  motion  by  securing  it  with  tape, 
clamps or ties at regular intervals. 
 
Common  sense  should  be  used  to  avoid  physical damage 
and minimize electrical noise.  For instance, avoid routing 
cables near high-voltage wires.  Do not route cables along 
floors  or  walkways  where  they  may  be  stepped  on  or 
become  contaminated.    To  avoid  ground  loops,  shielded 
cables  should  have  the  shield  grounded  at  one  end  only, 
typically at the signal conditioner. 

Summary of Contents for 3741B1210G

Page 1: ...elerometer 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 Fax 716 684 0987 E ma...

Page 2: ...ty regimen When in doubt about a calibration cycle a good rule of thumb is to recalibrate on an annual basis It is also good practice to recalibrate after exposure to any severe temperature extreme sh...

Page 3: ...rchase Order should include authorization to proceed and return at current pricing which can be obtained from a factory customer service representative Contact Information International customers shou...

Page 4: ...isclosure 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 O X O O O O O...

Page 5: ...e O O X O O 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 Indica...

Page 6: ...e applied acceleration The sensor element is electrically connected in a Wheatstone bridge circuit The integral amplifier provides a low impedance output to follow on instrumentation These particular...

Page 7: ...ssembly With each conductor being 30 AWG Teflon coated The supplied cable length for a standard DC accelerometer is 10 ft or 120 in 3 m Custom cable length requirements should be specified at time of...

Page 8: ...and stiff adhesives provide the best high frequency response METHOD 1 Adhesive Mounting Base This method involves attaching a base to the test structure then securing the sensor to the base This allow...

Page 9: ...es to reduce the effects of EMI and RFI that is present near electrical motors and machinery Teflon jacketed cabling may be necessary to withstand corrosive environments and higher temperatures Feel f...

Page 10: ...its provide the capability for continuous monitoring Note High sensitivity DC Accelerometers feature on board differential amplification 7 0 OPERATING NOTE Always operate the accelerometer within the...

Page 11: ...s and costly errors Therefore in an effort to prevent the common mistakes associated with customer performed calibration this document includes a broad overview of the Back to Back Calibration techniq...

Page 12: ...usly calibrated over the frequency and or amplitude range of interest 2 the shaker should be selected to provide minimal transverse lateral motion and minimal distortion and 3 the quality of the meter...

Page 13: ...eturn policies and instructions When unexpected measurement problems arise call our 24 hour SensorLineSM to discuss your immediate dynamic instrumentation needs with a factory representative Dial 716...

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