3B32

3B32 Isolated, Process Current Input Data Sheet (REV. 0)

Document overview

• Manufacturer or author: Provided By digicamel.com
• PDF pages: 8

Technical content

Isolated, Process Current Input 3B32 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 ri ghts of Analog Devices. Trademarks and registered trademarks are the property of their respective companies. Tel: 781.329.4700 www.analog.com Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.

FEATURES

Interfaces, amplifies, & filters a process-current input. Process-current input signals are measured by reading the voltage across an external precision 100Ω resistor (supplied with module). Module provides simultaneous precision voltage and current outputs. Module circuitry can withstand 220v rms at the input screw- terminals. All 3B32 series modules are mix-and-match and Hot Swappable.

APPLICATIONS

Industrial signal conditioning Industrial signal isolation Industrial signal filtering PRODUCT OVERVIEW The 3B Series of Signal Conditioning I/o Subsystems provide a low-cost, versatile method of transferring analog transducer signals to a data acquisition, monitoring or control system without the inherent noise, non-linearity, drift and extraneous voltages. The modules are designed to directly accept analog signals from Thermocouples, RTD’s, AC and DC Strain Gages, Torque Transducers, Frequency Transducers, LVDTs, millivolt or process current signals. The modules amplify, isolate, linearize and convert the transducer output signals to standardized analog inputs for high-level analog I/O subsystems. The 3B Series Subsystem consists of a 10” relay rack with universal mounting backplane and a family of plug-in (up to 16 per rack) input and output signal conditioning modules. Eight and four channel backplanes are also available. Each backplane incorporates screw terminals for sensor inputs and current outputs and a 26-pin connector for high-level single- ended voltage outputs to the user’s equipment. The input modules feature complete signal conditioning circuitry optimized for specific sensors or analog signals and provide two simultaneous high-level analog outputs: 0 to +10V (or + 10V) and 4-20 mA (or 0-20 mA). FUNCTIONAL BLOCK DIAGRAM Figure 1. 3B32 Functional Block Diagram input modules also provide +1500 V peak isolation. output is available on the output screw terminals.

Rev. 0 | Page 2 of 8 GENERAL DESCRIPTION The 3B32 is a single-channel signal conditioning module that interfaces, amplifies and filters a process-current input and provides simultaneous precision output voltage and current. Process-current input signals are measured by reading the voltage across an external precision 100Ω resistor (supplied). Model 3B32 performs complete signal conditioning, including isolating (+ 1500V peak input-to-output and power) and protecting their computer side outputs from damage and loss of signal integrity, and shielding their inputs from damage from field-side over-voltage faults up to 220V rms. The current output withstands 130V rms without damage and interfaces user equipment through screw terminals located on the 3B Series backplane. Each plug-in, mix-and-match, hot-swappable module is easily field calibrated via front-panel zero and span adjustments for both voltage and current outputs. 3B Series Custom-Ranging Program – Externally- programmable Model 3B32-00, enables the user to configure a special input range by using the optional plug-on AC1310 ranging card, which houses user-supplied resistors to determine zero and span. To facilitate selecting resistors, a Windows program, 3B-CUSTOM, calculates resistor values based on the user-desired input/output ranges. A chopper-stabilized low-drift (+ 1uV/oC) input amplifier assures long-term stability. At the amplifier input, a stable, zero-scale input voltage is subtracted from the input signal to set the zero-scale value. Zero suppression can exceed 100% of the input range. This is ideal for expanded-scale applications requiring high-resolution measurement of a selected portion of an input signal. For user convenience, the zero and span can be factory configured to meet custom range needs (Model 3B32- CUSTOM) or can be externally programmed (Model 3B32-00) via user supplied resistors inserted in the optional AC1310 plug- on ranging card. Internal low-pass filtering with a 3Hz cutoff (- 3dB) two-pole Butterworth filter enhances both 60 dB normal- mode and 160 dB common-mode rejection at 50/60 Hz, enabling accurate measurement of small signals in high electrical noise. Signal isolation is accomplished by transformer coupling with 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 and drives a voltage-to-current converter to provide the current output. Figure 2

Rev. 0 | Page 3 of 8 3B32 Models Available Model Input Range Output Ranges 1 3B32-00 Externally Programmable2 -10 V to ±10 V & 0 mA to 20 mA 3B32-01 4 mA to 20 mA 0 V to ±10 V & 4 mA to 20 mA 3B32-02 0 mA to20 mA 0 V to ±10 V & 4 mA to 20 mA 3B32-Custom * * 1 Output current range may be user programmed to 4 mA to 20 mA using jumper supplied. 2 Requires AC1310 ranging card. * Custom Input/Output ranges are available. Refer to configuration guide. 3B32 Specifications (typical @ +25°C and ±15 V dc, and +24 V dc Power) Description Model 3B32 Input Ranges Standard Ranges 0 mA to 20 mA; 4 mA to 20 mA Custom Ranges 0 mA to 20 mA (refer to ordering section) Output Ranges Voltage (RL > 2 KΩ) 0 V to +10 V; -10 V to +10 V Current (RL = 0 to 850Ω)1 4 mA to 20 mA or 0 mA to 20 mA Maximum Current Output Span 0 mA to 31 mA Accuracy2 Initial @ +25°C ±0.1% Span Nonlinearity ±0.01% Span Stability vs. Temperature Voltage Output Zero ±25 ppm of Span/°C Span ±25 ppm of Reading/°C Current Output Zero ±25 ppm of Span/°C Span ±25 ppm of Reading/°C Zero and Span Adjustment Range 4 ±5% of Span Input Resistor Value 100 Ω Accuracy ±0.1% Stability vs. Temperature ±0.002%/°C Input Bias Current +3 nA

Rev. 0 | Page 4 of 8 Input Resistance (Module) 15 MΩ Noise Input, 0.1 Hz to 10 Hz Bandwidth 0.2 µV rms Output, 100 kHz Bandwidth 50 µV rms Bandwidth, -3 dB 3 Hz Output Rise Time, 10% to 90% Span 200 ms Common-Mode Voltage (CMV) Input-to-Output, Continuous ±1500 V peak, maximum Transient ANSI/IEEE C37.90.1-1989 Common Mode Rejection (CMR) 1 kΩ Source Imbalance, 50/60 Hz 160 dB Normal Mode Rejection, 50/60 Hz 60 dB Input Protection Continuous 220 V rms maximum Transient ANSI/IEEE C37.90.1-1989 Voltage Output Protection Continuous Short to Ground Current Output Protection 130 V rms, continuous Power Supply Voltages 5 ±15 V dc Supplies Rated Operation ±(11.5 V dc to 16.5 V dc) Current ±10 mA Sensitivity ±0.01% span/V +24 V dc Loop Supply Rated Operation +12 V dc to +30 V dc Current +27 mA @ l out = 20 mA Sensitivity ±0.0002% span/V Mechanical Dimensions 3.15" x 3.395" x 0.775" (80.0 mm x 86.2 mm x 19.7 mm) Environmental Temperature Range Rated Performance -25°C to +85°C Storage -55°C to +85°C Relative Humidity, 24 hours 0 to 95% @ +60°C non-condensing RFI Susceptibility ±0.5% Span error @ 400 MHz, 5 Watt, 3 ft 1 For a 0 to 20 mA range, a typical minimum output current is 10 µA. 2 Includes the combined effects of repeatability, hysteresis, and nonlinearity. 3 With respect to the voltage output. 4 A wide range of custom zero suppression and span is available with the 3B32-00 model, using the AC1310 ranging card. 5 +24 V dc loop power is required for driving the current output at loads up to 850Ω. If a current output load of 400Ω or less is applied, +15 V dc is sufficient for loop power. If only voltage output is used, loop power is not required. Specifications subject to change without notice.

Figure 5. Outline Dimensions

Rev. 0 | Page 7 of 8 NOTES

Rev. 0 | Page 8 of 8 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the proper ty of their respective companies. D05094-0-9/04(0)