Isolated Voltage Input

7B31

Rev. 0

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FEATURES

Interfaces, amplifies, and filters unipolar and bipolar voltage

inputs.

Module provides a precision output of either +1 V to +5 V or

0 V to +10 V, linear with temperature.

Rated to operate with a nominal +24 VDC supply.

All 7B31 series modules are mix-and-match and Hot

Swappable.

APPLICATIONS

Industrial signal conditioning

Industrial signal isolation

Industrial signal filtering

PRODUCT OVERVIEW

The 7B Series of signal conditioners feature small size, low cost

and a wide output voltage range for a variety of applications

including process control and factory-floor environments. The

single-channel 7B modules accept inputs from a range of

rated for a nominal power supply input of +24 VDC; and, for

maximum flexibility, they will accept supply voltages in the +14

VDC to +35 VDC range. The input modules, with the exception

of the 7B21, provide a high-level output voltage that is factory

configured for either the +1 V to +5 V or 0 V to +10 V range.

The 7B21 is a unity gain, isolated input module with an

input/output range of +10V. Output modules are available that

provide either isolated process current or isolated bipolar

voltage output. Model 7B39 converts either a +1 V to +5 V input

to a 4 to 20 mA output or a 0 V to +10 V input to a 0-20 mA

output. The input/output ranges of the 7B39 are factory

configured. The 7B22 is a unity gain module that provides an

isolated +10V output signal. All modules have a universal pin-

out and may be readily hot-swapped under full power without

disrupting field wiring. Each module accepts analog transducer

signals and transfers them to a process control or factory data

collection system without the inherent noise, non-linearity, drift

and extraneous voltages which frequently accompany the

signals.

FUNCTIONAL BLOCK DIAGRAM

Figure 1. 7B31 Functional Block Diagram

The modules feature a maximum nonlinearity of +0.02% and

are factory calibrated to guarantee a maximum accuracy

specification of +0.1%.

The 7B Series offers up to 1500 V rms continuous common

mode voltage isolation and 120 V rms of field wiring input

protection. The power supplies necessary to drive each of the

individual module’s input circuitry are internally isolated,

enabling the 7B Series modules to offer true channel-to-channel

isolation of the input signals.

The modules directly accept analog signals from

thermocouples, RTDs, current loop powered transmitters, and

other process control signals. The 7B Series modules amplify,

linearize, isolate, protect and convert the transducer output

signals to standardized analog inputs for high-level analog I/O

subsystems. The 7B Series Subsystem consists of 19-inch rack-

compatible hardware (model AC 1363), with universal

mounting backplane and a family of plug-in (up to 16 per

backplane) input and output signal conditioning modules. Four-

, eight-, and sixteen-channel backplanes are available. Each

backplane incorporates screw terminals for easy power

connections and field wiring, and includes a 25-pin D-type

connector for interfacing the high-level single-ended voltage

outputs to the user’s equipment. Gold-plated sockets are

provided on each channel of the backplane to ensure the

reliability of each module’s electrical connection.