PCB Piezotronics 8120-400A User manual

Model 8120-400A
Strain Gage Sensor Signal Conditioner
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.

i
Table of Contents
Section 1.0 Description Page 1
Section 2.0 Installation and Cabling Page 1
Section 3.0 Calibration Page 7
Section 4.0 Calibration of PCB Rotary Transformer Torque Sensors Page 8
Section 5.0 Troubleshooting Page 9
Reference Figures
Figure 1 Bench Mounting Clearance Dimensions Page 2
Figure 2 Panel Mounting Cut-Out Dimensions Page 2
Figure 3 Panel Mount Assembly Page 3
Figure 4 Rack Mounting Dimensions Page 4
Figure 5 4200 Series Cabling Page 5
Figure 6 182-015A Connector Pin-Out Page 5
Figure 7 4-Conductor Cabling Page 5
Figure 8 4100 Series Cabling Page 5
Figure 9 8-Conductor Cabling Page 5
Figure 10 Remote Calibration Methods Page 6
Figure 11 Master / Slave Connections Page 6
Figure 12 Front Panel Descriptions Page 11
Figure 13 Rear Panel Descriptions Page 12
MODEL 8120-400A AC SIGNAL CONDITIONER OPERATION MANUAL
MANUAL NUMBER: 18222
REVISION: B
ECO NUMBER: 37012

MODEL 8120-400A AC SIGNAL CONDITIONER OPERATION MANUAL
1.0 DESCRIPTION
Model 8120-400A Transducer Signal
Conditioner/Amplifier is designed for use with
resistance strain gage transducers that require
an AC excitation-amplification source. It
supplies a 3.28 kHz frequency, precision
amplitude-regulated excitation, which is
remotely sensed to the transducer. The
instrument uses a phase-sensitive carrier
amplifier-demodulator design so that both
direction and magnitude of the applied force are
determined. The 8120-400A contains all
necessary balancing and calibration controls
and condition/amplify the applied input to a
standard ±5 volt DC analog output level. Two
analog outputs, both having low-pass cutoff
frequencies, one of 2 Hz and the other of 400
Hz, are provided. The filtered outputs provide
for averaging of signals containing noise or
other unwanted dynamic components that are
periodic in nature.
The 8120-400A is used in applications
involving transformer coupling of the strain
gage bridge (rotary transformer coupled torque
sensors for example), and in applications that
require a high sensitivity (amplification) with
optimum "signal to noise" characteristics.
Carrier amplifiers offer higher sensitivity than
comparable DC-excited bridge amplifiers, and
since they respond only to the modulated carrier
frequency, they reject certain extraneous
voltages that cause interference with DC-
excited bridge instruments.
Note: If you have a PCB rotary transformer
torque sensor, please refer to Section 3 of this
manual, or to either the 4100 Series Rotary
Transformer Torque Sensor Manual (PCB
Manual #18227), or the 4200 Series Rotary
Transformer Torque Sensor Manual (PCB
Manual #18228), for calibration procedures.
Calibration of the instrument is made through
conventional shunt technique, using an
internally installed calibration resistor, or an
external shunt calibration reference, such as our
Model 8113A or 8113-105A Shunt Calibration
References. Front panel calibration buttons
provide for calibration in both the positive and
negative directions. An internal symmetry
control provides independent adjustment of the
negative direction sensitivity for transducers
that do not have symmetrical positive and
negative slope characteristics. Positive
direction calibration can be checked by means
of REMOTE CAL terminals on the instrument
I/O connector.
The 8120-400A Strain Gage Conditioner is also
available in two additional forms. The 8120-
410A is similar to the 8120-400A except it also
contains a dedicated 4.5 digit LED display with
a 3Hz update rate. The resolution of the digital
display is 1:5000 (0.02% FS). The display also
has a selectable decimal point, trick count
multiplier, and a trailing inert zero. For more
information on instruments with digital display,
refer to PCB Manual #27259. The Model
8120-430A contains a Limit section (in addition
to a Digital Indicator) that provides
High/OK/Low indications and outputs. Refer to
PCB Manual #19479 for more information.
The Digital Indicator and Limit features are
standard to all 8120 Series Instruments.
2.0 INSTALLATION AND CABLING
The following paragraphs provide the
instructions for instrument installation and
cabling.
Mounting
The 8120 Series Instruments can be operated as
bench-top units or they can be rack or panel
mounted. Clearance dimensions for a bench-
mounted instrument are given in Figure 1 and
cut-out dimensions for panel mounting are
shown in Figure 2.
1

MODEL 8120-400A AC SIGNAL CONDITIONER OPERATION MANUAL
Figure 1 – Bench Mounting Clearance Dimensions
Figure 2 – Panel Mounting Cut-Out Dimensions
To panel mount an instrument, proceed as follows, referring to Figure 3.
Important: The unit is shipped with two spacer washers on the securing screws of the rear-panel I/O
connector. When panel-mounting the unit, you must remove these washers so that the printed circuit
board may move forward about 1/8" during Step (6).
1. Remove the front panel by removing the two #2-56 x 3/8” flat-head screws.
2. Remove the front bezel by removing the four #6-32 x 5/8” fillister-head screws.
3. Make the panel cut-out and drill the screw clearance holes indicated in Figure 2. The front
bezel can be used as a template to define the rectangular cut-out and locate the clearance holes.
4. Hold the instrument enclosure behind the panel and re-attach the front bezel to the enclosure
from the front of the panel with the four remaining screws.
5. Reinstall the front panel.
2

MODEL 8120-400A AC SIGNAL CONDITIONER OPERATION MANUAL
6. Tighten the two securing screws of the rear panel I/O connector to ensure that the connector is
seated and that the conditioner printed-circuit board is pushed fully forward so that the front-
panel screwdriver adjustments and buttons are accessible. These screws give approximately 1/8
inch adjustment; consequently, this is the maximum panel thickness that should be used.
Caution: Do not over tighten the connector securing screws or resultant damage may occur to the
printed-circuit board.
8120 SERIES
MODULE
Figure 3 – Panel Mount Assembly
To rack mount an instrument, refer to Figure 4. Up to four 8120 Series Instruments can be mounted in a
19-inch rack using the 1.75-inch high Model 8171A Rack Adaptor.
3

MODEL 8120-400A AC SIGNAL CONDITIONER OPERATION MANUAL
Figure 4 – Rack Mounting Dimensions
AC Power Connection
To protect operating personnel, the 8120 Series
Instruments are equipped with a three-
conductor power cord. When the cord is
plugged into the appropriate receptacle, the
instrument is grounded. The offset pin on the
power cord is ground. To maintain the safety
ground when operating the unit from a two-
contact outlet, use a three-prong to two-prong
adaptor and connect the green pigtail on the
adaptor to ground.
To prepare the instrument for operation,
connect the power cable to a 105-135 volt AC,
50-400 Hz power source. The instrument can
use up to 5 watts of power.
Calibration Resistor
If a fixed resistor is shunted across one arm of a
strain gage Wheatstone Bridge, it produces an
unbalance equivalent to that of a particular
value of mechanical input. If this Equivalent
Input value is accurately known, it can be used
as a reference point for shunt calibration of the
system. Upon completion of installation of the
transducer and its associated cabling, the user
can:
1. Perform an overall dead weight calibration
using a precisely known value of
mechanical input. Shunt calibration data
then can be collected by means of the
installed calibration resistor for
convenience in subsequent checking.
2. Replace the installed calibration resistor
with one (or an equivalent resistance value)
supplied by the transducer manufacturer to
achieve a precisely known Equivalent Input
allowing the instrument sensitivity to be
adjusted correctly.
3. Determine the Equivalent Input value for
the installed calibration resistor, knowing
the transducer sensitivity, and adjust the
instrument sensitivity accordingly.
4. A precision 59KΩcalibration resistor is
installed in the 8120 at the factory. The
installed resistor can usually be used even
though the transducer calibration data
mentions some other resistance value. In
Section 3 of this manual, the techniques
described above are demonstrated. If,
however, the installed value of calibration
resistor is not appropriate for the transducer
and measurement range to be used, the
59KΩresistor should be replaced at this
time. The calibration resistor is mounted
on solder terminals located at the front edge
of the conditioner printed-circuit board in
the instrument. It can be accessed by
removing the front panel.
Note: PCB 4200 Series Rotary Transformer
Torque Transducers are supplied with the
appropriate calibration resistor integral to the
transducer. When this type of transducer is
used with the 8120-400A, it is not necessary to
remove the 59KΩresistor internal to the
instrument. The calibration resistor can be
appropriately connected to the 8120-400A
calibration circuit via the transducer cabling.
Refer to Figure 5 and the following section.
4