DI-8B35 Linearized 4-Wire RTD Input Modules FEATURES • Interfaces to 100Ω Platinum RTDs • Linearizes RTD Signal • High Level Voltage Outputs • 1500Vrms Transformer Isolation • ANSI/IEEE C37.90.1 Transient Protection • Input Protected to 240VAC Continuous • 120dB CMR • 70dB NMR at 60Hz • Low Drift with Ambient Temperature • CSA, FM and CE Certifications Pending • Mix and Match Module Types SPECIFICATIONS DI-8B35 Input Range Limits Input Resistance -200˚C to +850˚C (100Ω Pt) Normal Power Off Overload Input Protection Sensor Excitation Current Lead Resistance Effect CMV, Input to Output Transient, Input to Output CMR (50Hz or 60Hz) NMR Accuracy³ DESCRIPTION DI-8B modules are an optimal solution for monitoring real-world process signals and providing high level signals to a data acquisition system. Each DI-8B35 module isolates, filters, amplifies, and linearizes a single channel of temperature input from an RTD and provides an analog voltage output. RTD excitation is provided from the module using a precision current source. Excitation current does not flow in the input signal leads, which allows RTD measurements to be made independent of lead resistance. The exciation currents are small (0.25mA) which minimizes self-heating of the RTD. Signal filtering is accomplished with a three-pole filter optimized for time and frequency response which provides 70dB of normal-mode-rejection at 60Hz. One pole of this filter is on the field side of the isolation barrier for anti-aliasing, and the other two are on the system side. A special input circuit on the DI-8B35 module provides protection against accidental connection of power-line voltages up to 240VAC. Clamp circuits on the I/O and power terminals protect against harmful transients. Typical at TA = +25ºC and +5V Power Stability Noise 50MΩ 200kΩ 200kΩ Continuous¹ Transient 240VAC ANSI/IEEE C37.90.1 0.25mA ±0.001˚C/Ω² 1500Vrms max ANSI/IEEE C37.90.1 120dB 70dB at 60Hz DI-8B35-01 DI-8B35-02 DI-8B35-03 DI-8B35-04 ±0.20˚C ±0.15˚C ±0.20˚C ±0.45˚C Output Offset Gain Output, 100kHz Bandwidth, -3dB Response Time, 90% Span Output Range Output Protection Transient Power Supply Voltage Power Supply Current Power Supply Sensitivity Mechanical Dimensions ±20ppm/ºC ±50ppm/ºC 250µVrms 3Hz 150ms 0 to +5V Continuous Short to Ground ANSI/IEEE C37.90.1 +5VDC ±5% 30mA ±25ppm/% 1.11" × 1.65" × 0.40" (28.1mm × 41.9mm × 10.2mm) Environmental Operating Temperature -40ºC to +85ºC Storage Temperature -40ºC to +85ºC Relative Humidity 0 to 95% Noncondensing ¹240VAC between + and - -/+EXC/-EXC terminals. 120VAC between - and +EXC/EXC terminals and between +EXC and -EXC terminals. ²Ω refers to the resistance in one lead. ³Includes conformity, hysteresis and repeatability. The modules are designed for installation in Class I, Division 2 hazardous locations and have a high level of immunity to environmental noise. DATAQ Instruments, Inc. • 241 Springside Drive • Akron, Ohio 44333 • Tel: 330-668-1444 • Email: [email protected] • www.dataq.com DI-8B35 4-Wire RTD Input Module Block Diagram Ordering Information Model Number Input Range DI-8B35-01 -100°C to +100°C (-148°F to +212°F) DI-8B35-02 0°C to +100°C (+32°F to +212°F) DI-8B35-03 0°C to +200°C (+32°F to +392°F) DI-8B35-04 0°C to +600°C (+32°F to +1112°F) *Includes conformity, hysteresis, and repeatability. Accuracy* ±0.20°C ±0.15°C ±0.20°C ±0.45°C 241 Springside Drive Akron, Ohio 44333 330-668-1444 Data Acquisition Product Links (click on text to jump to page) Data Acquisition | Data Logger | Chart Recorder | Thermocouple | Oscilloscope The information on this data sheet is subject to change without notice. DATAQ and the DATAQ logo are registered trademarks of DATAQ Instruments, Inc. All rights reserved. Copyright © 2005 DATAQ Instruments, Inc.