7B14

7B14 Non Isolated, Linearized RTD Input Data Sheet (REV. 0)

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Non Isolated, Linearized RTD Input 7B14 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

Amplifies, Protects, Filters, and Isolates input voltages from a wide variety of two and three-wire platinum, copper and nickel Resistor Temperature Detectors (RTDs). Module provides a precision output of either +1 V to +5 V or 0 V to +10 V, linear with temperature. All 7B14 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 transducers and are fully rated over the extended -40oC to +85oC industrial temperature range. 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. 7B14 Functional Block Diagram isolation of the input signals. reliability of each module’s electrical connection.

Rev. 0 | Page 2 of 8 GENERAL DESCRIPTION The 7B14 is a low cost, single-channel signal conditioning module that interfaces, amplifies and filters input voltages from a wide variety of two-and three-wire platinum, copper and nickel Resistor Temperature Detectors (RTDs) and provides a precision output of either +1 V to +5 V or 0 V to +10 V , linear with temperature. Model 7B14 features a nonlinearity of + 0.05% maximum (Pt and Cu RTDs). RTD excitation current, three- wire lead resistance compensation and a predictable upscale open circuit indication provide a complete signal conditioning solution. Rated to operate with a nominal +24 VDC supply, Model 7B14 is mix-and-match and hot-swappable with other 7B Series input modules, so it can be inserted or removed from any socket in the same backplane without disturbing system power. The three input pins of Model 7B14 are fully protected up to +30 VDC. A 250 uA excitation current for platinum and nickel RTDs and a 1mA excitation current for copper RTDs is provided to create an input voltage to the 7B14. This current also provides the upscale open circuit indication. A one-pole 3 Hz filter preconditions the RTD signal prior to amplification, provided by a low drift input amplifier. The output section contains a two-pole low pass filter (-3 dB @ 3 Hz) and a buffer amplifier. The two-pole output filter and subsequent buffer ensure that a low noise, low impedance (<1Ω) signal is available at the output to drive loads to 2 kΩ minimum. Figure 2

Rev. 0 | Page 3 of 8 7B14 Models Available Model RTD Sensor (2- or 3-wire) Input Range Output Range Nonlinearity (maximum) Accuracy (maximum) 7B14-01-1 100 Ω Pt, α = 0.00385 -100°C to +100°C +1 V to +5 V ±0.05% span ±0.15% span 7B14-01-2 100 Ω Pt, α = 0.00385 -100°C to +100°C 0 V to +10 V ±0.05% span ±0.15% span 7B14-02-1 100 Ω Pt, α = 0.00385 0°C to +100°C +1 V to +5 V ±0.05% span ±0.2% span 7B14-02-2 100 Ω Pt, α = 0.00385 0°C to +100°C 0 V to +10 V ±0.05% span ±0.2% span 7B14-03-1 100 Ω Pt, α = 0.00385 0°C to +200°C +1 V to +5 V ±0.05% span ±0.15% span 7B14-03-2 100 Ω Pt, α = 0.00385 0°C to +200°C 0 V to +10 V ±0.05% span ±0.15% span 7B14-04-1 100 Ω Pt, α = 0.00385 0°C to +600°C +1 V to +5 V ±0.05% span ±0.1% span 7B14-04-2 100 Ω Pt, α = 0.00385 0°C to +600°C 0 V to +10 V ±0.05% span ±0.1% span 7B14-05-1 100 Ω Pt, α = 0.00385 -50°C to +350°C +1 V to +5 V ±0.05% span ±0.1% span 7B14-05-2 100 Ω Pt, α = 0.00385 -50°C to +350°C 0 V to +10 V ±0.05% span ±0.1% span Model RTD Sensor (2- or 3-wire) Input Range Output Range Nonlinearity (maximum) Accuracy (maximum) 7B14-C-02-1 10 Ω Cu, α = 0.004274 0°C to +120°C (10 Ω @ +25°C) +1 V to +5 V ±0.05% span ±1.0% span 7B14-C-02-2 10 Ω Cu, α = 0.004274 0°C to +120°C (10 Ω @ +25°C) 0 V to +10 V ±0.05% span ±1.0% span Model RTD Sensor (2- or 3-wire) Input Range Output Range Nonlinearity (maximum) Accuracy (maximum) 7B14-N-01-1 120 Ω Ni, α = 0.00672 0°C to +300°C +1 V to +5 V ±0.12% span ±0.3% span 7B14-N-01-2 120 Ω Ni, α = 0.00672 0°C to +300°C 0 V to +10 V ±0.12% span ±0.3% span 7B14-N-02-1 120 Ω Ni, α = 0.00672 0°C to +200°C +1 V to +5 V ±0.14% span ±0.3% span 7B14-N-02-2 120 Ω Ni, α = 0.00672 0°C to +200°C 0 V to +10 V ±0.14% span ±0.3% span 7B14 Specifications (typical @ +23°C ±5°C and Vs = +24 V dc) Description Model 7B14 Input Ranges RTD Types 100 Ω Platinum, 2-, 3-wire, α =0.00385 120 Ω Nickel, 2-, 3-wire, α =0.00672 10 Ω Copper, α =0.004274 Temperature Ranges Refer to Model Table Custom Ranges Not Available* Output Range Options (RL > 2 kΩ) +1 V to +5 V or 0 V to +10 V Accuracy1 Initial @ +25°C Refer to Model Table

Rev. 0 | Page 4 of 8 Nonlinearity2 Refer to Model Table Input Offset vs. Temperature ±1 µV/°C Zero Suppression vs. Temperature ±0.002% (R z/Rspan)3/°C Span vs. Temperature ±60 ppm/°C Output Offset vs. Temperature ±0.002% Span/°C Lead Resistance Effect ±0.02°C/Ω Output Noise

5 MHz Bandwidth 1 mV peak

10 Hz to 100 Hz Bandwidth 0.4 mV rms 0.1 Hz to 10 Hz Bandwidth 0.6 µV peak Bandwidth, -3 dB 3 Hz Output Rise Time 250 ms Normal Mode Rejection @ 50/60 Hz 60 dB Input Protection ±30 V dc, continuous Input Transient Protection ANSI/IEEE C376.90.1-1989 IEEE-STD 472 IEC 255-4, Class II Output Resistance < 1 Ω Voltage Output Protection Continuous Short to Ground Power Supply Voltage Range, Operating +14 V dc to +35 V dc Current +25 mA, maximum Sensitivity ±0.0001%/% of Vs Mechanical Dimensions 1.663" x 2.11" x 0.563" (42.24 mm x 53.6 mm x 14.3 mm) Environmental Temperature Range Operating -40°C to +85°C Storage -40°C to +85°C Relative Humidity, 24 hours 0 to 90% @ +60°C noncondensing ESD Sensitivity IEC 801-2, Level 2 RFI Susceptibility ±0.5% Span error @ 400 MHz, 5 Watt, 3 ft Warm-up time required to meet specifications is approximately 10 minutes. * Contact factory for OEM requirements. 1 Includes the combined effects of repeatability, hysteresis, and nonlinearity. 2 Nonlinearity is calculated using best-fit straight line method. 3 Rz is the value of the RTD resistance at the lowest measurement point. Rspan is the change in resistance over the measurement span. Specifications subject to change without notice.

Table 1. Pin Function Descriptions—

0 SENSOR INPUT NOT USED

1 INPUT HIGH OUTPUT HIGH

2 INPUT LOW OUTPUT LOW

3 POWER SUPPLY (DC) POWER SUPPLY (DC)

4 OUTPUT VOLTAGE INPUT VOLTAGE

5 OUTPUT & POWER

Figure 4 . Model 7B Series Module, with pin-out assignments. protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.

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. D05168-0-9/04(0)