Isolated Process Current Output 3B39 FUNCTIONAL BLOCK DIAGRAM FEATURES Interfaces, isolates, & filters a 0 to +10V or -10V to +10V input signal and provides an isolated process current output across loads of 0 to 850 .. Intended for high-accuracy process control and monitoring applications requiring total galvanic isolation. Module circuitry can withstand 220v rms at the output screw-terminals. All 3B39 series modules are mix-and-match and Hot Figure 1. 3B39 Functional Block Diagram Swappable Output modules accept 0 to +10V (or +10V) single-ended signals and provide an isolated 4-20 mA (or 0-20 mA) process APPLICATIONS signal. All modules feature a universal pin-out and may be Industrial signal conditioning readily hot-swapped under full power and interchanged without Industrial signal isolation disrupting field wiring. Industrial signal filtering The Analog Devices 3B Series Signal Conditioning Subsystem is designed to easily handle signal conditioning problems in PRODUCT OVERVIEW measurement and control applications. Some typical uses are in The 3B Series of Signal Conditioning I/o Subsystems provide a microcomputer-based data acquisition systems, programmable low-cost, versatile method of transferring analog transducer controllers, analog recorders, dedicated control systems, and any signals to a data acquisition, monitoring or control system other applications where monitoring of temperature, pressure, without the inherent noise, non-linearity, drift and extraneous flow and analog signals are required. Since each input module voltages. The modules are designed to directly accept analog features two simultaneous outputs, the voltage output can be signals from Thermocouples, RTDs, AC and DC Strain Gages, used to provide an input to a microprocessor-based data Torque Transducers, Frequency Transducers, LVDTs, millivolt acquisition or control system while the current output can be or process current signals. The modules amplify, isolate, used for analog transmission, operator interface, or an analog linearize and convert the transducer output signals to backup system. standardized analog inputs for high-level analog I/O Each input module is a single-channel signal conditioner which subsystems. The 3B Series Subsystem consists of a 10 relay plugs into a socket on the backplane and accepts its signal from rack with universal mounting backplane and a family of plug-in the input screw terminals. All input modules provide input (up to 16 per rack) input and output signal conditioning protection, amplification and filtering of the input signal, modules. o accuracy of +0.1%, low drift of +1 uV/ C (low-level input Eight and four channel backplanes are also available. Each modules), and feature two high-level analog outputs that are backplane incorporates screw terminals for sensor inputs and compatible with most process instrumentation. The isolated current outputs and a 26-pin connector for high-level single- input modules also provide +1500 V peak isolation. ended voltage outputs to the users equipment. The choice of a specific 3B module depends upon the type of The input modules feature complete signal conditioning input signal. Input modules are available to accept millivolt, volt, circuitry optimized for specific sensors or analog signals and process current, thermocouple, RTD, AC and DC strain gage, provide two simultaneous high-level analog outputs: 0 to +10V frequency and LVDT inputs. The voltage output of each module (or +10V) and 4-20 mA (or 0-20 mA). is available from the sysem 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. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective companies. Fax: 781.326.8703 2004 Analog Devices, Inc. All rights reserved. 3B39 GENERAL DESCRIPTION modulation technique for linear, stable and reliable The 3B39 is a single-channel signal conditioning current output performance. A demodulator on the output side of the signal module that interfaces, isolates and filters a 0 to +10V or -10V transformer recovers the original signal, which is then filtered to +10V input signal and provides an isolated process current and converted to an accurate current output by a current (V-to- output across loads of 0 to 850. The output current appears at I) converter output stage. Output protection enables the 3B39 to the 3B Series backplane current output screw terminal block. It withstand accidental connection to 220V rms power lines is intended for high-accuracy process control and monitoring without damage, isolating computer-side circuitry. The 3B39 applications requiring complete galvanic isolation and provides total ground isolation and transient protection when protection against damage from transients and faults between interfacing DACs to standard 4-20 mA current loops, common systems or separated system elements. Either of the two input requirement in microcomputer based control system. voltage ranges can be converted to either of the two output current ranges via programming jumpers provided on the bottom of the module. Model 3B39 features a nonlinearity of +0.01% and an accuracy of +0.1%. Providing +1500V peak of galvanic transformer based isolation output-to-input and power, the 3B39 offers a common mode rejection (CMR) of 90 dB 50/60 Hz to preserve the integrity of low level signals in noisy environments. The 3B39 is mix-and-match and hot-swappable with other 3B Series modules, so it can be inserted or removed from any socket in the same backplane without disturbing . system power. Signal isolation by transformer coupling uses a proprietary Figure 2 Rev. 0 Page 2 of 8