Isolated High Level Voltage Input

7B21

Rev. 0

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FEATURES

Unity gain single-channel signal conditioning module that

interfaces, filters, and isolates a +10 Volt input signal.

Features a nonlinearity of +0.02% maximum and an

accuracy of +0.1% maximum.

All 7B21 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

All 7B Series modules are 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. 7B21 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.