AD 3B17-03

Wide Bandwidth LVDT/RVDT Input
3B17
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Isolates, amplifies, & filters signals from 4-, 5, or 6-wire
Linear Variable Displacement Transformers (LVDTs).
Isolates, amplifies, & filters signals from Rotary Variable
Displacement Transformers (RVDT).
Provides an AC excitation voltage of 1V rms to 5V rms at
frequencies between 1 kHz and 10kHz.
Module circuitry can withstand 130v rms at the input screwterminals.
All 3B17 series modules are mix-and-match and Hot
Swappable.
Figure 1. 3B17 Functional Block Diagram
APPLICATIONS
Industrial signal amplification
Industrial signal isolation
Industrial signal filtering
PRODUCT OVERVIEW
The 3B Series of Signal Conditioning I/o Subsystems provide a
low-cost, versatile method of transferring analog transducer
signals to a data acquisition, monitoring or control system
without the inherent noise, non-linearity, drift and extraneous
voltages. The modules are designed to directly accept analog
signals from Thermocouples, RTD’s, AC and DC Strain Gages,
Torque Transducers, Frequency Transducers, LVDTs, millivolt
or process current signals. The modules amplify, isolate,
linearize and convert the transducer output signals to
standardized analog inputs for high-level analog I/O
subsystems. The 3B Series Subsystem consists of a 10” relay
rack with universal mounting backplane and a family of plug-in
(up to 16 per rack) input and output signal conditioning
modules.
Eight and four channel backplanes are also available. Each
backplane incorporates screw terminals for sensor inputs and
current outputs and a 26-pin connector for high-level singleended voltage outputs to the user’s equipment.
The input modules feature complete signal conditioning
circuitry optimized for specific sensors or analog signals and
provide two simultaneous high-level analog outputs: 0 to +10V
(or +10V) and 4-20 mA (or 0-20 mA).
Output modules accept 0 to +10V (or +10V) single-ended
signals and provide an isolated 4-20 mA (or 0-20 mA) process
signal. All modules feature a universal pin-out and may be
readily hot-swapped under full power and interchanged without
disrupting field wiring.
The Analog Devices 3B Series Signal Conditioning Subsystem is
designed to easily handle signal conditioning problems in
measurement and control applications. Some typical uses are in
microcomputer-based data acquisition systems, programmable
controllers, analog recorders, dedicated control systems, and any
other applications where monitoring of temperature, pressure,
flow and analog signals are required. Since each input module
features two simultaneous outputs, the voltage output can be
used to provide an input to a microprocessor-based data
acquisition or control system while the current output can be
used for analog transmission, operator interface, or an analog
backup system.
Each input module is a single-channel signal conditioner which
plugs into a socket on the backplane and accepts its signal from
the input screw terminals. All input modules provide input
protection, amplification and filtering of the input signal,
accuracy of +0.1%, low drift of +1 uV/oC (low-level input
modules), and feature two high-level analog outputs that are
compatible with most process instrumentation. The isolated
input modules also provide +1500 V peak isolation.
The choice of a specific 3B module depends upon the type of
input signal. Input modules are available to accept millivolt, volt,
process current, thermocouple, RTD, AC and DC strain gage,
frequency and LVDT inputs. The voltage output of each module
is available from the system I/O connector while the current
output is available on the output screw terminals.
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective companies.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
www.analog.com
Tel: 781.329.4700
Fax: 781.326.8703
© 2004 Analog Devices, Inc. All rights reserved.
3B17
GENERAL DESCRIPTION
excitation voltage amplitude and frequency. To facilitate
selecting resistors, a Windows program, 3B-CUSTOM,
calculates resistor values based on the user-desired input/output
ranges and AC excitation.
The 3B17 is a wide-bandwidth single-channel signalconditioning module which isolates, amplifies, and filters
signals from 4-, 5-, or 6-wire Linear Variable Displacement
Transformers (LVDTs) or Rotary Variable Displacement
Transformers (RVDT). The 3B17 input module provides an AC
excitation voltage of 1V rms to 5V rms at frequencies between 1
kHz and 10 kHz. All gain and zero suppression can be usercalibrated by screwdriver adjustments through the sliding door
on the top of the module. Gain can vary over an extensive 256:1
range by adjusting a combination of a rotary switch and trim
potentiometer. Zero suppression can vary over +5V from the
center setting. The current output can be independently
adjusted over a +5% range for zero and span. In addition, the
3B17 is mix-and-match and hot-swappable with all 3B Series
modules, so it can be inserted or removed from any socket in
the same backplane without disrupting system power.
The 3B17 input and AC excitation output terminals are
protected for up to 130V rms, protecting the computer side
from damage due to field-side over-voltage faults. The LVDT
input signal is amplified to give the high level output voltage.
The 3B17 automatically compensates for phase errors between
the primary and secondary of the LVDT or RVDT, eliminating
the need for a phase adjustment and automatically rejects any
residual quadrature voltages via a unique approach to error
compensation which uses the sum of the two secondary
winding to directly drive the demodulator. The amplitude and
frequency of the AC excitation can be factory configured to
meet custom needs (Model 3B17-Custom) or externally
configured (Models 3B17-00 and 3B17-D-00) with the optional
AC1310 plug-on custom ranging card.
3B Series Custom-Ranging Program – Externallyprogrammable Model 3B17-00, and 3B17-D-00, enable the user
to configure a special input range, excitation voltage and
excitation frequency by using the optional plug-on AC1310
ranging card, which houses user-supplied resistors to determine
.
.
Figure 2
Rev. 0 | Page 2 of 8
3B17
3B17 Models Available
Model
Excitation Voltage
Excitation Frequency
Output Ranges1
3B17-00
Externally Programmable2
Externally Programmable2
-10 V to +10 V & 0 mA to 20 mA
3B17-01
3 V rms
2.5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-02
5 V rms
5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-03
5 V rms
7.5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-04
1 V rms
10 kHz
-10.0 V to +10 V & 0 mA to 20 mA
3B17-Custom
*
*
2
*
2
3B17-D-00
Externally Programmable
3B17-D-01
3 V rms
2.5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-D-02
5 V rms
5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-D-03
5 V rms
7.5 kHz
-10 V to +10 V & 0 mA to 20 mA
3B17-D-04
1 V rms
10 kHz
-10 V to +10 V & 0 mA to 20 mA
Externally Programmable
-10 V to +10 V & 0 mA to 20 mA
1
Output current range may be user programmed to 4 mA to 20 mA using jumper supplied.
Requires AC1310 ranging card.
* Custom Input/Output ranges are available. Refer to configuration guide.
2
3B17 Specifications
(typical @ +25°C and ±15 V dc, and +24 V dc Power)
Description
Model 3B17
Input Range
Types
4-, 5-, 6-wire LVDT or RVDT, including differential coils
Standard Range
20 mV rms to 5 V rms; See Model Table for Excitation
Voltage and Frequency
Custom Excitation
Vexc = 1 V rms to 5 V rms
Vexc freq. = 1 kHz to 10 kHz
Output Range
Voltage (RL > 2 KΩ)
-10 V to +10 V
Current (RL = 0 to 850Ω)1
4 mA to 20 mA or 0 mA to 20 mA
With Input Overload
40 mA, maximum
Accuracy2
Initial @ +25°C
2
Nonlinearity
±0.1% Span
±0.05% Span
Stability vs. Temperature
Voltage Output
Zero
±0.005% of Span/°C
Span
Current Output
±0.01% of Span/°C
3
Zero
±25 ppm of Span/°C
Span
±25 ppm of Reading/°C
LVDT Excitation4
Rev. 0 | Page 3 of 8
3B17
Voltage
1 V rms to 5 V rms
Voltage, tolerance
±10%
Frequency
1 kHz to 10 kHz, ±15%
Drive
20 mA rms, minimum
Harmonic Distortion
< 0.5%
Voltage Output Calibration4
Span Adjustment Range
256:1
Zero Adjustment Range
±5 V
Current Output Calibration4
Zero and Span Adjustment Range
±5% of Span
Input Bias Current
+1 µA
Input Resistance
100 MΩ
5
Bandwidth , -3 dB
100 Hz
Output Rise Time, 10% to 90% Span
5 ms
Input Protection, Signal and Excitation Voltage
Continuous
130 V rms maximum
Transient
ANSI/IEEE C37.90.1-1989
Voltage Output Protection
Continuous Short to Ground
Current Output Protection
130 V rms, continuous
±15 V dc Supplies
Rated Operation
±(13 V dc to 18 V dc)
Current
±65 mA plus LVDT Current7
Sensitivity
±0.03% span/V
+24 V dc Loop Supply
Rated Operation
+13.5 V dc to +30 V dc
Current
+27 mA @ lout = 20 mA
Sensitivity
±0.001% span/V
Mechanical Dimensions
3.15" x 3.395" x 0.775"
80.0 mm x 86.2 mm x 19.7 mm)
Environmental
Temperature Range
Rated Performance
-25°C to +85°C
Storage
-55°C to +85°C
Relative Humidity, 24 hours
0 to 95% @ +60°C non-condensing
RFI Susceptibility
±0.5% Span error @ 400 MHz, 5 Watt, 3 ft
1
For a 0 mA to 20 mA range, a typical minimum output current is 10 µA.
Includes the combined effects of repeatability, hysteresis, and nonlinearity.
With respect to the voltage output.
4
A wide range of custom zero suppression and span is available with the 3B17-00 model, using the AC1310 ranging card.
5
Bandwidth can be set for up to 1/10 the excitation frequency when ordering Model 3B17-custom.
6
+24 V dc loop power is required for driving the current output at loads up to 850Ω. If a current output load of 400Ω or less is applied, +15 V dc is sufficient for loop power. If only
voltage output is used, loop power is not required.
7
Typical supply current is ±40 mA per module plus ±5 mA for the LVDT drive current. To calculate supply current requirements from LVDT currents, use 75% of the LVDT rms
current.
Specifications subject to change without notice.
2
3
Rev. 0 | Page 4 of 8
3B17
PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS
Table 1. Pin Function Descriptions—
Pin No.
1
2
3
4
Description
LO IN
CJC OUT
HI IN
CJC COM
Figure 4 . Model 3B Series Module, with pin-out assignments.
Figure 3 3B17 Input Field Connections
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human
body and test equipment and can discharge without detection. Although this product features proprietary ESD
protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges.
Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
Rev. 0 | Page 5 of 8
3B17
OUTLINE DIMENSIONS
Figure 5. Outline Dimensions
Rev. 0 | Page 6 of 8
3B17
NOTES
Rev. 0 | Page 7 of 8
3B17
NOTES
© 2004 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective companies.
D05090-0-9/04(0)
Rev. 0 | Page 8 of 8