Analog Devices B47 Datasheet

Isolated, Linearized Thermocouple Input

FEATURES

Isolated Thermocouple Input.
Amplifies, Protects, Filters, and Isolates Thermocouple Input
Works with J, K, T, E, R, S, and B-type thermocouple.
Generates aisolated and protected precision output of 0 to

+5V.
Module circuitry can withstand 240v rms at the input screw-

terminals.
All 5B47 series modules are mix-and-match and Hot

Swappable.

APPLICATIONS

Industrial signal conditioning
Industrial signal isolation
Industrial signal filtering

PRODUCT OVERVIEW

The 5B Series represents an innovative generation of low cost,
high performance plug-in signal conditioners. Designed for
industrial applications, these modules incorporate highly
reliable transformer-based isolation and automated surface­mount manufacturing technology. They are compact,
economical components whose performance exceeds that
available from more expensive devices. Combining 1500 V rms
continuous isolation, +0.05% calibrated accuracy, small size and
low cost, the 5B Series is an attractive alternative to expensive
signal conditioners and in-house designs

All modules are potted and identical in pin-out and size (2.27” x

2.32” x 0.595”). They can be mixed and matched, permitting
users to address their exact needs, and may be “hot swapped
without disturbing field wiring or power. The isolated input
modules provide 0 to +5V or +5V outputs and accept J, K, T, E,
R, S, N, or B type thermocouples.

5B47

Figure 1. 5B47 Functional Block Diagram

There are also a number of backplanes and mounting sockets
which provide a complete signal conditioning solution for end
users. Each backplane incorporates screw terminals for field
wiring inputs and outputs and cold junction sensors for
thermocouple applications.

These signal conditioners are designed to provide an easy and
convenient solution to signal conditioning problems of both
designers and end users in measurement and control
applications. Typical uses include microcomputer-based
measurement systems, standard data acquisition systems,
programmable controllers, analog recorders and dedicated
control systems. The 5 B series modules are ideally suited to
applications where monitoring and control of temperature,
pressure, f low, rotation and other analog signals are required.

The 5B Series modules and backplanes are approved by Factory
Mutual (FM) and the 5B Series modules are approved by the
Canadian Standards Association (CSA) for use in Class 1,
Division 2, Groups A, B, C, and D locations. These approvals
certify that the 5B Series is suitable for use in locations where a
hazardous concentration of flammable gas may exist only under
fault conditions of operation. Equipment of this category is
called “nonincendive” and they need no special enclosures or
other physical safeguards.

These modules feature complete signal conditioning functions
including 240 V rms input protection, filtering, chopper
stabilized low drift +1 uV/oC amplification, 1500 V rms
isolation, and sensor excitation when required.

All modules feature excellent common mode rejection and
meet industrial transient surge withstand specifications.

FUNCTIONAL BLOCK DIAGRAM

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.

The 5B series modules and backplanes have been tested and
passed the stringent heavy industrial requirements of the
European Union’s electromagnetic compatibility (ENC)
directive – EN50082-1 and EN50081-2. When used according
to installation directions (refer to 5B series User Manual), any
errors caused by EMI/RFI interference will be less than 0.1% of
the full scale 5B measurement range for field strengths up to 10
V/M and frequencies up to 1 GHz.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.

www.analog.com

GENERAL DESCRIPTION

The 5B47 is a single-channel signal conditioning module that
interfaces, amplifies and filters J, K, T, E, R, S, and B-type
thermocouple. The module provides an isolated and protected
precision output of 0 to + 5 V.

The 5B47 internally linearizes its input signal to provide an
output that is linear with temperature. Accuracy for each type of
sensor is specified in the 5B47 model table. (See Model 5B37 for
non-linearized conditioning of thermocouple signals.)

Accurate and System-Ready - Internal cold-junction
compensation largely corrects errors arising from parasitic
thermocouples formed by thermocouple connection to the
input screw terminals, providing an accuracy of +

25oC ambient temperature. The module generates a

+
predictable upscale signal to indicate an open thermocouple; for
a downscale response, connect a 20MΩ, 0.25W resistor across
screw terminals 1 and 3.

The 5B47 protects the computer side from damage due to field­side over-voltage faults. All models withstand 240V rms at their
input terminals without damage, thereby shielding computer­side circuitry from field-side over-voltage conditions. Further,
the 5B47 is mix-and-match and hot-swappable with other 5B
Series modules, so can be inserted or removed from any socket
in the same backplane without disrupting system power.

Inside the 5B47 Module – A chopper-stabilized input amplifier
provides low drift and stable gain. At the amplifier input, a

.

0.25oC @

5B47

stable, laser-trimmed zero-scale input voltage is subtracted from
the input signal to set the zero-scale value. For user
convenience, the zero can be optionally factory-set to meet
custom needs. This allows suppression of a zero-scale input
value many times larger than the total span for precise
expanded-scale measurements.

Internal multi-pole low-pass filtering with a 4-Hz cutoff (-3 dB)
provides 60 dB of normal-mode rejection (noise on signal) and
enhancement of common-mode rejection (noise on signal
return) at 60 Hz, enabling accurate measurement of small
signals in high electrical noise.

Signal isolation by transformer coupling uses a proprietary
modulation technique for linear, stable and reliable
performance. The differential input circuit on the field side is
fully floating, eliminating the need for any input grounding. A
demodulator on the computer side of the signal transformer
recovers the original signal, which is then filtered and buffered
to provide a low-noise, low-impedance output signal. The
output common must be kept within +

A series output switch eliminates the need for external
multiplexing in many applications. The switch is turned on by
an active-low enable input. If the switch is to be on at all times,
the enable-input should be grounded to power common as it is
on the 5B01 and 5B08 backplanes.

3 V of power common.

.

Figure 2

Rev. 0 | Page 2 of 8

5B47 Models Available

Model Input Type Input Range Output Range Accuracy1

5B47-J-01
5B47-J-02
5B47-J-03
5B47-K-04
5B47-K-05
5B47-T-06
5B47-T-07
5B47-E-08
5B47-R-09
5B47-S-10
5B47-B-11

5B47-Custom

1

The CJC sensor accuracy should be added to the module accuracy for a system accuracy.

* Custom Input/Output ranges are available. Refer to conf ig ur ation guide.

Type J 0°C to +760°C (+32°F to +1400°F) 0 V to +5 V ±1.1°C
Type J -100°C to +300°C (-148°F to +572°F) 0 V to +5 V ±0.5°C
Type J 0°C to +500°C (+32°F to +932°F) 0 V to +5 V ±0.6°C
Type K 0°C to +1000°C (+32°F to +1832°F) 0 V to +5 V ±1.3°C
Type K 0°C to +500°C (+32°F to +932°F) 0 V to +5 V ±0.6°C
Type T -100°C to +400°C (-148°F to +752°F) 0 V to +5 V ±1.4°C
Type T 0°C to +200°C (+32°F to +392°F) 0 V to +5 V ±0.5°C

Type E 0°C to +1000°C (+32°F to +1832°F) 0 V to +5 V ±1.7°C
Type R +500°C to +1750°C (+932°F to +3182°F) 0 V to +5 V ±2.5°C
Type S +500°C to +1750°C (+932°F to +3182°F) 0 V to +5 V ±2.4°C
Type B +500°C to +1800°C (+932°F to +3272°F) 0 V to +5 V ±5.1°C

Type J, K, T, E, R, S, B * *

5B47

5B47 Specifications

Description Model 5B47

Input Ranges

Standard Ranges Refer to Model Table
Custom Ranges ±5 mV to ±500 mV

Output Ranges (RL > 50 k Ω)

Accuracy

Initial @ +25°C See Model Table
Input Offset vs. Temperature2 ±1 µV/°C
Output Offset vs. Temperature ±20 µV/°C
Gain vs. Temperature ±0.0025% of Reading/°C

Cold Junction Compensation

Initial Accuracy @ +25°C3 ±0.25°C (±0.75°C, maximum)
Accuracy, +5°C to +45°C ±0.5°C (±0.0125°C/°C)

Input Bias Current

Input Resistance

Power On
Power Off
Overload

Noise

Input, 0.1 Hz to 10 Hz Bandwidth 0.2 µV rms

+1 V to +5 V or 0 V to +5 V

1

-25 nA

5 M Ω
40 k Ω
40 k Ω

Rev. 0 | Page 3 of 8