PCB Piezotronics ICP 123A24 User manual

Model 123A24
Rocket motor ICP® pressure sensor, 1000 psi, 5 mV/psi, Helium bleed,
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: [phone]
E-mail: [email protected]
Web: www.pcb.com

Manual 21354 Rev E
ECN 50523
Repair and Maintenance
PCB guarantees Total Customer Satisfaction through its
“Lifetime Warranty Plus” on all Platinum Stock Products
sold by PCB and through its limited warranties on all other
PCB Stock, Standard and Special products. Due to the
sophisticated nature of our sensors and associated
instrumentation, field servicing and repair is not
recommended and, if attempted, will void the factory
warranty.
Beyond routine calibration and battery replacements
where applicable, our products require no user
maintenance. Clean electrical connectors, housings, and
mounting surfaces with solutions and techniques that will
not harm the material of construction. Observe caution
when using liquids near devices that are not hermetically
sealed. Such devices should only be wiped with a
dampened cloth—never saturated or submerged.
In the event that equipment becomes damaged or ceases
to operate, our Application Engineers are here to support
your troubleshooting efforts 24 hours a day, 7 days a
week. Call or email with model and serial number as well
as a brief description of the problem.
Calibration
Routine calibration of sensors and associated
instrumentation is necessary to maintain measurement
accuracy. We recommend calibrating on an annual basis,
after exposure to any extreme environmental influence,
or prior to any critical test.
PCB Piezotronics is an ISO-9001 certified company whose
calibration services are accredited by A2LA to ISO/IEC
17025, with full traceability to SI through N.I.S.T. In
addition to our standard calibration services, we also offer
specialized 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 more
information, contact your local PCB Piezotronics
distributor, sales representative, or factory customer
service representative.
Returning Equipment
If factory repair is required, our representatives will
provide you with a Return Material Authorization (RMA)
number, which we use to reference any information you
have already provided and expedite the repair process.
This number should be clearly marked on the outside of
all returned package(s) and on any packing list(s)
accompanying the shipment.
Contact Information
PCB Piezotronics, Inc.
3425 Walden Ave.
Depew, NY14043 USA
Toll-free: [phone]
24-hour SensorLine: [phone]
General inquiries: in[email protected]
Repair inquiries: [e-mail]
For a complete list of distributors, global offices and sales
representatives, visit our website, www.pcb.com.
Safety Considerations
This product is intended for use by qualified personnel
who recognize shock hazards and are familiar with the
precautions required to avoid injury. While our equipment
is designed with user safety in mind, the protection
provided by the equipment may be impaired if equipment
is used in a manner not specified by this manual.
Discontinue use and contact our 24-Hour Sensorline if:
Assistance is needed to safely operate equipment
Damage is visible or suspected
Equipment fails or malfunctions
For complete equipment ratings, refer to the enclosed
specification sheet for your product.
Definition of Terms and Symbols
The following symbols may be used in this manual:
DANGER
Indicates an immediate hazardous
situation, which, if not avoided, may
result in death or serious injury.

Manual 21354 Rev E
ECN 50523
CAUTION
Refers to hazards that could damage
the instrument.
NOTE
Indicates tips, recommendations and
important information. The notes
simplify processes and contain
additional information 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 precautions to avoid
personal contact with this voltage.
This symbol on the unit indicates that
the user should refer to the operating
instructions located in the manual.
This symbol indicates safety, earth
ground.

Manual 21354 Rev E
ECN 50523
PCB工业监视和测量设备 - 中国RoHS2公布表
PCB Industrial Monitoring and Measuring Equipment - China RoHS 2 Disclosure Table
部件名称
有害物质
铅(Pb)
汞
(Hg)
镉
(Cd)
六价铬(Cr(VI))
多溴联苯 (PBB)
多溴二苯醚(PBDE)
住房
O
O
O
O
O
O
PCB板
X
O
O
O
O
O
电气连接器
O
O
O
O
O
O
压电晶体
X
O
O
O
O
O
环氧
O
O
O
O
O
O
铁氟龙
O
O
O
O
O
O
电子
O
O
O
O
O
O
厚膜基板
O
O
X
O
O
O
电线
O
O
O
O
O
O
电缆
X
O
O
O
O
O
塑料
O
O
O
O
O
O
焊接
X
O
O
O
O
O
铜合金/黄铜
X
O
O
O
O
O
本表格依据 SJ/T 11364 的规定编制。
O：表示该有害物质在该部件所有均质材料中的含量均在 GB/T 26572 规定的限量要求以下。
X：表示该有害物质至少在该部件的某一均质材料中的含量超出 GB/T 26572 规定的限量要求。
铅是欧洲RoHS指令2011/65/ EU附件三和附件四目前由于允许的豁免。
CHINA RoHS COMPLIANCE

Manual 21354 Rev E
ECN 50523
Component Name
Hazardous Substances
Lead (Pb)
Mercury (Hg)
Cadmium (Cd)
Chromium VI
Compounds
(Cr(VI))
Polybrominated
Biphenyls (PBB)
Polybrominated
Diphenyl Ethers
(PBDE)
Housing
O
O
O
O
O
O
PCB Board
X
O
O
O
O
O
Electrical Connectors
O
O
O
O
O
O
Piezoelectric Crystals
X
O
O
O
O
O
Epoxy
O
O
O
O
O
O
Teflon
O
O
O
O
O
O
Electronics
O
O
O
O
O
O
Thick Film Substrate
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: Indicates that said hazardous substance contained in all of the homogeneous materials for this part is below the limit
requirement of GB/T 26572.
X: Indicates that said hazardous substance contained in at least one of the homogeneous materials for this part is above the limit
requirement of GB/T 26572.
Lead is present due to allowed exemption in Annex III or Annex IV of the European RoHS Directive 2011/65/EU.

Drawing Number: 21091 ECO: 45804
Revision: A
OPERATION MANUAL FOR
HELIUM BLEED WATER-COOLED
PRESSURE SENSORS
Models 123A, 123A21, 123A22, 123A23, & 123A24
1
1.0 INTRODUCTION
The series of sensors described in this guide is
designed to measure dynamic pressures in intense
thermal environments typified by rocket engine
combustion chambers.
These sensors feature acceleration-compensated
piezoelectric pressure probes mounted in a helium
bleed adaptor with water cooling.
The helium gas, applied from a 1500 psi source, is
metered by a built-in orifice and flows around the
probe body and out the passage of the adaptor head of
the probe diaphragm. The helium gas flowing out the
passage protects the sensor diaphragm from the hot
gasses as well as increasing the natural frequency of
the passage by a factor of approximately three to one.
2.0 DESCRIPTION
The Model 123A contains a one pC/psi pressure
probe (sensor) and is designed to be used with
electrostatic charge amplifiers such as the PCB
Model 462A.
The Models 123A21, A22, A23, and A24 contain
built-in impedance converter electronics circuits
which convert the high-impedance voltage from the
quartz crystal to a low-impedance voltage signal that
can be fed directly into most common indicating or
recording instruments.
The 123A series sensors contain a 10 micro helium
filter contained in a fitting threaded onto the helium
input tube. The purpose of this filter is to prevent
particles in the helium supply from plugging the
metering orifice.
The outer body of this series is 17-4 PH hardened
stainless steel and features a ceramic-coated tip for
protection against erosion by hot gasses when the
sensor is flush-mounted directly in combustion
chambers.
The probes in all models are electrically ground
isolated from the outer housing.
Series 123A: Water- Cooled & Helium Bleed
Rocket Motor, ICP®and Charge Sensors
NOTE: The sensor probe in this series is factory
installed at a precise depth in the outer body. Do not
attempt removal of this probe. Contact the factory
should any questions or problems arise concerning
the sensor probe.
3.0 INSTALLATION
Prepare mounting port in accordance with
instructions on installation drawing 123-1010-90 or
123-1210-90.
Inspect the mounting port for burrs and tool marks at
the seal surface.
Use recommended mounting torque when installing
sensors. Do not overtorque as damage to seal surface
could result.

Drawing Number: 21091 ECO: 45804
Revision: A
OPERATION MANUAL FOR
HELIUM BLEED WATER-COOLED
PRESSURE SENSORS
Models 123A, 123A21, 123A22, 123A23, & 123A24
2
NOTE: When attaching helium supply hose, do not
torque hose fitting through helium tube on sensor.
Back up fitting with wrench on 3/8 hex on helium
hose fitting. (Refer to note 3 on installation drawing.)
Especially in the presence of high vibration, support
helium supply tubes by clamping to rigid surfaces
with adequate strain relief loop to avoid stressing
helium tube on sensor.
Follow the same procedures and apply similar
precautions when installing the water supply and
drain hoses. Either water tube may be used as the
inlet tube. Use at least a 50 psi source of clean water
for cooling.
For charge output Model 123A, connect 4 ft. cable to
charge amplifier and switch to "LONG" time constant
position and check for drift.
Clean cable connections with Trycloror equivalent
solvent to restore insulation resistance.
It is good practice to depress ground button (or place
switch in "GND" position) on the charge amplifier
while attaching input cables to the amplifier. This
will prevent spurious charges which may accumulate
on sensors and cables from blowing out the input
circuitry of the charge amplifier.
Since the charge output sensors are susceptible to
decreased insulation resistance, use care to keep cable
connections clean by use of shrink tubing wherever
possible.
The Models 123A21, A22, A23 and A24 Sensors use
low-output impedance probes (ICP) and will not
require the insulation resistance cautions previously
described for Model 123A.
Connect the sensor cable to the appropriate ICP
power unit and check the front panel monitor meter to
check cable connections and internal amplifier.
Consult Guide G-0001B, "General Guide to ICP
Instrumentation" for installation and usage hints for
ICPinstruments.
Sensor connection for ICP®operation
4.0 OPERATION
4.1 CHARGE OUTPUT MODEL 123A
For the Model 123A charge output, it is only
necessary to select the proper range on the charge
amplifier and proceed with the measurement.
The probe sensitivity is approximately 1.0 pC/psi.
(The exact sensitivity is given on the calibration
certificate supplied with each instrument.)
EXAMPLE: The dynamic pressure expected is
500 psi and the desired output voltage for this
pressure is 1 volt.
Simply set the range switch of the charge amplifier to
500 units per volt and dial the standardization pot to
the exact sensor sensitivity at 500 psi (from
calibration graph).
The system will then yield exactly 1 volt for 500 psi
of input pressure (dynamic).

Drawing Number: 21091 ECO: 45804
Revision: A
OPERATION MANUAL FOR
HELIUM BLEED WATER-COOLED
PRESSURE SENSORS
Models 123A, 123A21, 123A22, 123A23, & 123A24
3
4.2 TIME CONSTANT
During in-place calibration static methods (dead
weight tester) may be used in a drift-free system by
placing the charge amplifier in "LONG TC" position.
However, during actual use, the TC mode switch
should be in "SHORT" position for two reasons.
Often times, the dynamic pressure being measured
exists superimposed upon a higher static level. The
short TC position will allow the effect of this static
level to zero out quickly without effect on the
dynamic level indicated.
Also, the influx of large amounts of thermal energy,
as in rocket combustion measurements, can cause the
sensor to generate spurious transient outputs of
considerable magnitude. Using the charge amplifier
on "SHORT" TC alleviates this problem by shunting
these longer term charge outputs to ground while
measuring the faster dynamic pressure pulses.
4.3 OPERATION - ICPMODELS
123A21, A22, A23, and A24
Consult Guide G-0001B for a complete description of
the low-impedance concept in instrumentation.
All PCB power units designed for ICPuse contain
built-in fault monitor meters to aid in locating circuit
faults (shorts or opens) and to identify normal
operation of the miniature impedance-converting
amplifier built into the sensor.
Do not attempt to apply voltage directly to the input
pin of the sensor from any other power source. The
input current must be limited to 20 mA maximum and
the input voltage must not be higher than 28 VDC.
Consult the factory if it is desired to build a power
unit rather than to use one of those available from
PCB.
The Models 123A21, A22, A23, and A24 are
identical except for sensitivity.
The Model 123A21 has a sensitivity of 20 mV/psi
which gives a full-scale range (for +5 V out) of 250
psi.
The Model 123A22 has a sensitivity of 1.0 (for +3 V
out) mV/psi and a full-scale range of 3000 psi.
The Model 123A23 has a sensitivity of 0.5 mV/psi
and a full-scale range of 10,000 psi.
The Model 123A24 has a sensitivity of 5.0 mV/psi
and a full-scale range of 1000 psi.
NOTE: Full-scale range is 1imited by the helium
source pressure. The helium source pressure must be
at least twice the peak combustion pressure (static
plus dynamic) to be measured, but not more than
about 10 times the lowest pressure. This is true for
all models, charge or ICP.
5.0 CALIBRATION
5.1 CHARGE MODEL 123A
To calibrate this model, install in pressure port of
dead weight tester and apply various static pressures,
recording corresponding outputs at each pressure of
interest.
Discharge the charge amplifier before each reading
and return pressure to zero before each new pressure
input. Use the charge amplifier on “LONG” time
constant and keep cables and connections clean to
avoid drift. A DC digital voltmeter is ideal for
readout during calibration.
NOTE: The helium tube must be plugged with a
pressure-tight seal before attempting to calibrate to
avoid losing pressure through the helium tube.
If a hydraulic calibration system is used, be sure to
remove all traces of oil from the diaphragm passage
after calibration. Pneumatic systems are preferred for
calibration.
5.2 ICPMODELS 123A21, A22, A23
& A24
Because of the shorter time constants built into these
models, static calibration methods are much more
difficult to use. Pressures must be applied rapidly
and readout must be made with fast recording devices
such as light beam oscillographs or storage
oscilloscopes.
A pneumatic (compressed air or hydrogen) system
with quick opening valve and reference gage is an
excellent method of calibrating these sensors.

Drawing Number: 21091 ECO: 45804
Revision: A
OPERATION MANUAL FOR
HELIUM BLEED WATER-COOLED
PRESSURE SENSORS
Models 123A, 123A21, 123A22, 123A23, & 123A24
4
To take full advantage of the constant built into the
sensor, use a DC-coupled power unit such as the PCB
Model 484B06.
MAINTENANCE
The sealed construction and miniature size of these
sensors make field repair impractical.
The helium filter element should be cleaned should
the flow rate decrease. Remove the element and
ultrasonically agitate in solvent for 15 minutes, then
dry.
Should the orifice become plugged, back pressure the
orifice by applying air pressure to diaphragm end of
sensor with filter off and helium tube vented to
atmosphere.
The only maintenance possible on the probe is
maintaining of insulation resistance of the Model
123A Probe/Cable Assembly. Clean connectors with
suitable solvent and dry.
Contact factory for assistance should problems arise.
ICP is a registered trademark of PCB Piezotronics

Model Number
123A24
Revision: H
ECN #: 51279
Performan ce EN GLISH SI
Measurement Range(for ±5V output) 1,000 psi 6,895 kPa
Sensitivity(± 15 %) 5.0 mV/psi 0.725 mV/kPa
Maximum Pressure 5,000 psi 34,475 kPa
Resolution 0.02 psi 0.138 kPa [1]
Resonant Frequency ≥ 25.0 kHz ≥ 25 kHz [2]
Rise Time(Reflected) ≤ 20.0 µ sec ≤ 20.0 µ sec [2]
Low Frequency Response(- 5 %) 0.005 Hz 0.005 Hz
Non-Linearity ≤ 1.0 % FS ≤ 1.0 % FS [3]
Environm en tal
Acceleration Sensitivity ≤ 0.002 psi/g ≤ 0.0014 kPa/(m/s²)
Temperature Range(Operating) -100 to +250 °F -73 to +121 °C [4]
Temperature Coefficient of Sensitivity ≤ 0.03 %/°F ≤ 0.054 %/°C
Maximum Flash Temperature 10,000 °F 5,538 °C
Maximum Vibration 2,000 g pk 19,600 m/s² pk
Maximum Shock 10,000 g pk 98,070 m/s² pk
Electrical
Output Polarity(Positive Pressure) Positive Positive
Discharge Time Constant(at room temp) ≥ 100 sec ≥ 100 sec
Excitation Voltage 20 to 30 VDC 20 to 30 VDC
Constant Current Excitation 2 to 20 mA 2 to 20 mA
Output Impedance ≤ 100 Ohm ≤ 100 Ohm
Output Bias Voltage 8 to 12 VDC 8 to 12 VDC
Ph ysical
Housing Material 17-4 Stainless Steel 17-4 Stainless Steel
Diaphragm Invar Invar
Sealing Epoxy Epoxy
Electrical Connector Integral Cable Integral Cable
Weight 4.23 oz 120 gm
Helium Flow Rate(at 1,500 psi) 40 scf/hr 1.13 m³/hr
Cable Length 4 ft 1.2 m
Water Flow Rate(at 50 psi) 1.2 gal/min 4.5 L/min
[5]
All specifications are at room temperature unless otherwise specified.
In the interest of constant product improvement, we reserve the right to change specifications without notice.
ICP® is a registered trademark of PCB Piezotronics, Inc.
OPTION A L VERSION S
Optional versions have identical specifications and accessories as listed for the standard model except
where noted below. More than one option may be used.
NOTES:
[1]Typical.
[2]With helium flow.
[3]Zero-based, least-squares, straight line method.
[4]Applies to internal amplifer, not to external housing.
[5]See PCB Declaration of Conformance PS023 for details.
Date: 12/23/2020 Date: 12/23/2020 Date: 12/23/2020 Date: 12/23/2020 5019
Entered: LK Engineer: NJL Sales: MV Approved: RPF Spec Number:
3425 Walden Avenue, Depew, NY 14043
Phone: [phone]
Fax: [phone]
E-Mail: i[email protected]
SUPPLIED ACCESSORIES:
Model 065A15 Seal, .624" OD x .553" ID x .080", brass (3)
Model 070A08 Cable adaptor (micro 10-32 jack to BNC jack) (1)

FLUSH MOUNT RECESS MOUNT
1
1
2
2
3
3
4
4
A A
B B
CODE
IDENT. NO.
52681
DWG. NO.
SCALE: SHEET
DRAWN CHECKED ENGINEER
TITLE
UNLESS OTHERWISE SPECIFIED TOLERANCES ARE:
DIMENSIONS IN MILLIMETERS
[ IN BRACKETS ]
XX ±0.13
ANGLES 2 DEGREES
3425 WALDEN AVE. DEPEW, NY 14043
[phone] E-MAIL: [e-mail]
DIMENSIONS IN INCHES
DECIMALS XX ±.01
ANGLES 2 DEGREES
FILLETS AND RADII
.003 - .005
DECIMALS X ± 0.3
FILLETS AND RADII
0.07 - 0.13
INSTALLATION DRAWING
123-1210-90
1 OF 1
1.5X
MODELS 123A21,22,23 & 24
HELIUM BLEED WATER COOLED SENSOR
XXX ±.005
ECB 8/18/16 ECB 8/18/16 BAM 8/18/16
123-1210-90
PCB Piezotronics Inc. claims proprietary rights in
the information disclosed hereon. Neither it nor any
reproduction thereof will be disclosed to others
without the written consent of PCB Piezotronics Inc.
REVISIONS
REV DESCRIPTION DIN
JUPDATE TOLERANCE ON MOUNTING HOLE 45725
HELIUM INPUT, AN TYPE FITTING
5/16-24 UNF-2A
WATER TUBE, AN TYPE FITTING
5/16-24 UNF-2A
MODEL 031A HELIUM FILTER
10 MICRON (SUPPLIED AND ASSEMBLED AT PCB)
ELECTRICAL CONNECTOR
COAXIAL 10-32 UNF-2A
1.00[25.4] HEX
MODEL 006EB004EB
ARMORED CABLE
4 ft [1.2 M] LONG
MODEL 065A15 SEAL
(SUPPLIED)
PROTECTIVE CERAMIC COATING
2.2 [55]
2.0 [50]
.66 [16.6]
.080 [2.03]
.68 [17.3]
M14x1.25 - 6g
.010 [0.25]
MOUNTING HOLE PREPARATION
M14x1.25-6H THRU
.625±.001[15.88±.02] .060[1.52]
MOUNTING HOLE PREPARATION
.100[2.54] THRU
M14x1.25-6H .720[18.29]
.625±.001[15.88±.02] .060[1.52]
1
11
2
3
4
SEAL SURFACE MUST BE FLAT AND FREE OF TOLL MARKS WITH A 63 [1.5] FINISH
RECOMMENDED MOUNTING TORQUE ON 1.00[25.4] HEX: 10-15 ft-lbs [13-20 Nm]
SUPPORT .375[9.53] HEX ON FILTER WHEN ATTACHING LINE TO AVOID DAMAGE TO HELIUM INPUT TUBE
RECOMMENDED MOUNTING TORQUE: 15-30 in-lbs [1.7-3.4 Nm]
4
43
2
.71 [18.0]
.91 [23.1] MIN