Analog Devices 7B Series Signal Conditioning 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 transducers and are fully rated over the extended -40°C to + 85°C industrial temperature range.

All 7B Series modules are rated for a nominal power supply input of +24 V DC; and, for maximum flexibility, they will accept supply voltages in the +14 V DC to +35 V DC 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 ±10 V. 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 ±10 V 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. 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 AC1363), 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.

Features

Accepts a Wide Range of Process Control and Factory Data Collection Signals: mA, mV, RTDs and Thermocouples

Process Current Output Modules 4 - 20 mA & 0 - 20 mA

Powered mA Input Module Includes Isolated Power for a Remote Transmitter, Sufficient to Drive a 4 mA to 20 mA Current Loop

Bipolar Voltage Input and Output Modules

"Hot Swappable" Mix and Match Ability Under Full Power Without Disrupting Field Wiring

Operates From a Single +24 V DC Power Supply

Provides +1 V to +5 V, 0 V to +10 V and ±10 V Output Options

Factory Calibrated to ±0.1% Maximum Accuracy

Isolates up to 1500 V rms continuous CMV and 120 V rms Continuous Field Wiring Protection

Fully Rated Over the -40°C to +85°C Industrial Temperature Range

Packaged in a Compact 2.1-inch x 1.7-inch x 0.6-inch Durable Plastic Package

CSA Approved for Use in Class I, Division 2, Groups A, B, C and D Hazardous Locations

CE Approval: All 7B Modules and Backplanes Meet the European Union's EMC Directive

Input Module Features and Benefits

Isolated Signal Conditioners with choice of isolation levels.

Accepts wide variety of process control and factory data collection sensor inputs: thermocouples, RTDs and two-wire current loop powered transmitters.

Millivolt, Volt and Milliamp Inputs.

Non-isolated, Low Cost, RTD model.

"Hot Swappable" under power.

Low drift of ±0.001% span /°C over entire rated -40°C to +85°C industrial temperature range.

High accuracy of ±0.1% maximum. Maximum nonlinearity of ±0.02%.

Input protection of up to 120 V rms continuous.

Output Module Features and Benefits

Bipolar ±10 V Input and Output Modules.

Current Output Modules provide 4 mA to 20 mA or 0 to 20 mA output.

High-Level Voltage Inputs.

Output protection of continuous short to ground.

Reliable gold-plated pin and socket connections.

Reliable transformer isolation to 1500 V rms continuous.

Low drift of ±0.001% span /°C over entire rated -40°C to +85°C industrial temperature range.