Documentation Number FBDA0797 Manual
Cover Page
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Strain Gauge/Load Cell Bridge Amplifier
Model FBDA
Documentation Number FBDA0797
This product
Designed and Manufactured
In Ottawa, Illinois
USA
of domestic and imported parts by
B&B Electronics Mfg. Co. Inc.
707 Dayton Road -- P.O. Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Internet:
http://www.bb-elec.com
orders@bb-elec.com
support@bb.elec.com
1997 B&B Electronics
Not Recommended for New Installations.
Please contact Technical Support for more information.
Documentation Number FBDA0797 Manual
Table of Contents
i
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
TABLE OF CONTENTS
CHAPTER 1: INTRODUCTION.................................................................1
F
EATURES
...............................................................................................1
P
ACKING
L
IST
..........................................................................................2
S
OFTWARE
..............................................................................................2
C
ALIBRATION
...........................................................................................2
FBDA S
PECIFICATIONS
............................................................................2
CHAPTER 2: CONNECTIONS..................................................................3
P
OWER
S
UPPLY
C
ONNECTIONS
................................................................3
S
ENSOR
C
ONNECTIONS
............................................................................3
D
ATA
A
CQUISITION
C
ONNECTIONS
............................................................4
CHAPTER 3: GAIN SELECTION..............................................................7
CHAPTER 4: EXCITATION VOLTAGE ....................................................9
Documentation Number FBDA0797 Manual
1
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Chapter 1: Introduction
Features
The FBDA is a signal conditioning module that allows you to
measure voltages produced by full-bridge sensors using a data
acquisition module. This module can condition signals from Strain
Gauges, Load Cells, Pressure Sensors, and other Full-Bridge
Transducer Sensors. A number of different gain settings are
available on the FBDA to accommodate a wide variety of voltage
ranges. The FBDA also provides an adjustable excitation voltage for
the full-bridge circuitry. The sensor connections are made using
terminal blocks, and the A/D connections are made through a DB-25
connector. B&B Electronics' SDAXX, and ADIO12 data acquisition
modules are pin compatible with the FBDA. This allows you to
simply plug one of the data acquisition modules mentioned above
into the FBDA, and the A/D connections are complete. The SPDA
data acquisition modules can also be used with the FBDA.
Figure 1.1: FBDA Module
2
Documentation Number FBDA0797 Manual
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Packing List
Examine the shipping carton and the contents for physical
damage. The following items should be in the shipping carton:
1. FBDA module
2. This instruction manual
If any of these items are damaged or missing, contact B&B
Electronics immediately.
Software
Software is not included with the FBDA module. This device is
used in conjunction with a data acquisition device. All of B&B
Electronics' data acquisition modules come complete with software
that you can modify to meet your exact needs.
Calibration
The FBDA is calibrated at the factory. The excitation
voltage is set to 5VDC 0.05VDC and the gain is calibrated at 80
2. The process of calibrating the FBDA and your sensor will vary
depending on the type of sensor being used. An example calibration
procedure is covered in Chapter 3.
FBDA Specifications
Size:
4.8
x
2.2
x
0.9
in
Maximum Input Voltage from Sensor: 440mV (using Gain = 25)
Output
Voltage
Range: 0.003V
to
11VDC
Gain:
25,
40,
80,
220-1000
Maximum Gain Error:
5% of gain setting max.
Input
Offset
Voltage: 150
V max.
Input
Offset
Voltage
Drift:
1.5
V/
o
C
Excitation
Voltage:
0.5VDC
to
+11VDC
Operating Temperature Range:
0 to 70
o
C
Power
Requirements:
13-18VDC
@10mA
(does
not include current draw
from excitation voltage.)
Documentation Number FBDA0797 Manual
3
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Chapter 2: Connections
Power Supply Connections
The FBDA module requires 13 to 18VDC @ 10mA. Model
232PS2 available from B&B Electronics is recommended. Although
the 232PS2 is a 12VDC power supply, it outputs a voltage above
13VDC when less than 10mA are being drawn from it. The power
supply is connected to the terminal blocks marked +13V and GND.
Make sure the polarity of the power supply is correct (the white
striped wire on the 232PS2 is the positive lead).
Sensor Connections
Most full-bridge sensor circuits require four connections for the
sensor to operate properly. These connections will be made using
the terminal blocks. First, an excitation voltage is required to excite
the bridge circuitry. This can be done using the adjustable excitation
voltage (marked EXV) available on the FBDA, or another voltage
source can be furnished by the user. This excitation voltage is
referenced with respect to ground, which is the second connection
(marked GND). The remaining two leads from the sensor carry the
differential signal voltage that is to be conditioned and read by the
data acquisition module. These two leads are connected to SIG+
and SIG-. Consult your sensor manual to determine the signal lead
polarity. Table 2.1 shows the terminal block assignments.
Note: A/D 1 is connected straight through from the terminal blocks
to DB-25 pin # 9. This allows access to A/D channel 1 on B&B
Electronic's SDAXX line of A/D converters. This channel can read
voltages between 0 and 5VDC (useful for calibrating the excitation
voltage). This channel has no signal conditioning circuitry. It is
simply connected to A/D 1 on the data acquisition module.
Table 2.1: Terminal Block Assignments
Terminal
Block Name
Function I/O
SIG+
Positive Signal Lead
Input
SIG-
Negative Signal Lead
Input
EXV Excitation
Voltage
Output
A/D 1
A/D Converter channel
Input
+13V
Power Supply Connection
Input
GND
Power Supply Connection
Input
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