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Drawing Number: 21067 
Revision: A 

 

PIEZOELECTRIC CHARGE MODE PRESSURE SENSOR GENERAL OPERATION MANUAL 

5 

If  thermal  transients  or  diaphragm  impingement  are 
concerns,  use  the  flush  mount  technique  only  when 
space or frequency response considerations preclude the 
use of the recess mount installation. 
 
In  severe  or  pyrotechnic  environments,  sensor  life  may 
be seriously curtailed when using this mounting method. 
 

3.4 

Flash Thermal Protection 

 
Several  additional  steps  may  be  taken  to  provide 
protection  from  flash  thermal  effects.    The  sensor 
diaphragm  may  be  thermally  insulated  at  the  factory, 
using a thin (.010 inches / 0.254 mm) coating of ablative 
silicone rubber, G.E. type 580 (“A” option).  Before the 
insulation  is  applied,  the  surface  of  the  diaphragm  is 
treated with SS4004 primer. 
 
If more protection is required, the recess mount may be 
filled  with  DC-4  silicone  grease  or  its  equivalent.    In 
place of the silicone rubber, one or more layers of black 
vinyl  electrical  tape  on  the  diaphragm  may  provide 
sufficient insulation. 
 

3.5 

Miscellaneous Installation Notes 

 
Thread adaptors, such as the Series #61, 3/8-24 or Series 
#62,  1/8  NPT,  provide  quick  installation  where 
mounting  port  diameter  is  not  limited.    Other  adaptors 
include Series #63 Needle Probe, and Series #64 Water-
Cooled.    Adaptor  use  simplifies  mounting  procedures 
and  improves  troubleshooting  by  reducing  the  incorrect 
data  that  can  result  from  improper  mounting.      See  the 
PCB General Catalog for details. 
 
A  floating  clamp  nut,  Model  060A03  (Model  060A05 
for metric), 1/4 hex, facilitates mounting and removal of 
the  sensor  by  clamping  the  sensor  in  place  without 
placing  undue  stress  on  the  quartz  element.    The clamp 
nut  is  provided with either standard (5/16-24) or metric 
(M7 x 0.75) threads and is supplied along with three seal 
rings. 
 
Model  008A  Hardline  Cable  is  recommended  for 
operating  temperatures  above  500°F.    This  cable  is 
supplied in lengths up to 40 feet (12,19 m). 

 

 
 

3.6 

Cabling 

 
Care and attention to cable attachment is essential, as the 
reliability and accuracy of your system is no better than 
that  of  the  output  cable.    First,  check  that  you  have 
ordered  the  correct  cable  type.    As  with  sensors,  no 
cable  can  satisfy  all  applications.    Special  low-noise 
cabling should be used (e.g., PCB Series 003) with high-
impedance, charge output devices. 
 
Connect  the  cable  to  the  pressure  sensor.    A  small 
amount  of  thread  locking  compound  placed  on  the 
connector  prior  to  attachment  helps  secure  the  cable 
during  testing.    For  additional  protection  in  harsh 
environments,  the  connection  may  be  sealed  with 
protective materials, such as silicon rubber, O-rings and 
flexible heat-shrink tubing (optional). 
 

 

 
Plug  the  male  connector  on  the  cable  into  the  mating 
female  connector  on  the  sensor.    Then,  holding  the 
sensor  stationary,  secure  the  connector  in  place  by 
tightening  down  the  attached  cable  sleeve.  See  Figure 
3.3. 
 
Route  the  cable  to  a  charge  amplifier  or  in-line  charge 
converter,  making  certain  to  strain  relieve  the 
sensor/cable  connection  and  minimize  motion  by 
clamping  the  cable at regular intervals.  Common sense 
must  be  used  to  avoid  physical  damage  and  minimize 
electrical noise.  Avoid routing cables near high voltage 
wires.    Do  not  route  cables  along  floors  or  walkways 
where they may be stepped on or become contaminated.  
Shielded  cable  should  have  the  shield  grounded  at  one 
end only. 
 
To  dissipate  any  charge  that  may  have  accumulated  in 
the cable, short the signal to ground prior to attachment 
to the charge amplifier or charge converter. 
 

Summary of Contents for 116B

Page 1: ...re Sensor 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 mai...

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: ...that the sensor is supplied with optional features A option Ablative thermal barrier E option Emralon coating H option Hermetic seal J option Electrical isolation mounting adaptor required M option Me...

Page 7: ...ies 113A High Frequency Miniature Sensor The Series 113A High Frequency Miniature Sensor is a charge mode pressure sensor designed to measure shock wave blast explosion ultrasonic and dynamic combusti...

Page 8: ...rage pressure level over a wide amplitude range and a usable frequency range near DC to between 5 000 and 10 000 Hz the resonant frequency is 25 000 Hz The Model 171 is extremely sensitive with a nomi...

Page 9: ...nd L length of column feet For air at room temperature the equation becomes L 3300 Fr Where L passage length inches The natural frequency and approximately fastest pressure step rise time for various...

Page 10: ...z element The clamp nut is provided with either standard 5 16 24 or metric M7 x 0 75 threads and is supplied along with three seal rings Model 008A Hardline Cable is recommended for operating temperat...

Page 11: ...nce charge signal generated by the sensor into a low impedance voltage signal This signal may then be transmitted to a readout or recording device for analysis See Figure 5 1 for a drawing of a typica...

Page 12: ...DC offset voltage usually very tiny microvolts that exists at the input gate of the MOSFET circuit This minute leakage current exists in all real devices As demonstrated in Equation 1 the steady state...

Page 13: ...1 Introduction 6 4 Low Frequency Response Limitations In a normal charge amplifier the low frequency response is set by the RC time constant as established by the product of Cf and Rf The system acts...

Page 14: ...umulated electrostatic charges may build to the point that they may saturate or even damage the input circuitry of the charge amplifier Operate the charge amplifier in the SHORT time constant while th...

Page 15: ...se specified In the interest of constant product improvement we reserve the right tochange specifications without notice ICP is a registeredtrademarkof PCB Piezotronics Inc E Emralon coating Electrica...

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