Isolated Thermocouple Input 5B37 FEATURES Interfaces, amplifies and filters J, K, T, E, R, S, B, N, and C-type Thermocouple. Generates an isolated and protected precision output of 0 to +5V. Module circuitry can withstand 240v rms at the input screwterminals. All 5B37 series modules are mix-and-match and Hot Swappable. APPLICATIONS Industrial signal conditioning Industrial signal isolation Industrial signal filtering PRODUCT OVERVIEW The 5B Series represents an innovative generation of low cost, high performance plug-in signal conditioners. Designed for industrial applications, these modules incorporate highly reliable transformer-based isolation and automated surfacemount manufacturing technology. They are compact, economical components whose performance exceeds that available from more expensive devices. Combining 1500 V rms continuous isolation, +0.05% calibrated accuracy, small size and low cost, the 5B Series is an attractive alternative to expensive signal conditioners and in-house designs All modules are potted and identical in pin-out and size (2.27” x 2.32” x 0.595”). They can be mixed and matched, permitting users to address their exact needs, and may be “hot swapped without disturbing field wiring or power. The isolated input modules provide 0 to +5V or +5V outputs and accept J, K, T, E, R, S, N, or B type thermocouples. These modules feature complete signal conditioning functions including 240 V rms input protection, filtering, chopper stabilized low drift +1 uV/oC amplification, 1500 V rms isolation, and sensor excitation when required. All modules feature excellent common mode rejection and meet industrial transient surge withstand specifications. FUNCTIONAL BLOCK DIAGRAM Figure 1. 5B37 Functional Block Diagram There are also a number of backplanes and mounting sockets which provide a complete signal conditioning solution for end users. Each backplane incorporates screw terminals for field wiring inputs and outputs and cold junction sensors for thermocouple applications. These signal conditioners are designed to provide an easy and convenient solution to signal conditioning problems of both designers and end users in measurement and control applications. Typical uses include microcomputer-based measurement systems, standard data acquisition systems, programmable controllers, analog recorders and dedicated control systems. The 5 B series modules are ideally suited to applications where monitoring and control of temperature, pressure, flow, rotation and other analog signals are required. The 5B Series modules and backplanes are approved by Factory Mutual (FM) and the 5B Series modules are approved by the Canadian Standards Association (CSA) for use in Class 1, Division 2, Groups A, B, C, and D locations. These approvals certify that the 5B Series is suitable for use in locations where a hazardous concentration of flammable gas may exist only under fault conditions of operation. Equipment of this category is called “nonincendive” and they need no special enclosures or other physical safeguards. The 5B series modules and backplanes have been tested and passed the stringent heavy industrial requirements of the European Union’s electromagnetic compatibility (ENC) directive – EN50082-1 and EN50081-2. When used according to installation directions (refer to 5B series User Manual), any errors caused by EMI/RFI interference will be less than 0.1% of the full scale 5B measurement range for field strengths up to 10 V/M and frequencies up to 1 GHz. 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 rights of Analog Devices. Trademarks and registered trademarks are the property of their respective companies. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. www.analog.com Tel: 781.329.4700 Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved. 5B37 GENERAL DESCRIPTION optionally factory-set to meet custom needs. This allows suppression of a zero-scale input value many times larger than the total span for precise expanded-scale measurements. The 5B37 is a single-channel signal conditioning module that interfaces, amplifies and filters J, K, T, E, R, S, B, N, and C-type thermocouple and provides an isolated and protected precision output of 0 to +5V. Internal multi-pole low-pass filtering with a four Hz cutoff (-3 dB) provides 60 dB of normal-mode rejection (noise on signal) and enhancement of common-mode rejection (noise on signal return) at 60 Hz, enabling accurate measurement of small signals in high electrical noise. Accurate and System-Ready – Internal cold-junction compensation largely corrects errors arising from parasitic thermocouples formed by thermocouple connection to the input screw terminals, providing an accuracy of +0.25oC @ +25oC ambient temperature. The module generates a predictable upscale signal to indicate an open thermocouple, for a downscale response, connect a 47MΩ, 0.25 W resistor across screw terminals 1 and 3. Signal isolation by transformer coupling uses 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 to provide a low-noise, low-impedance output signal. The output common must be kept within 3 V of power common. The 5B37 protects the computer side from damage due to fieldside over-voltage faults. All models withstand 240V rms at their input terminals without damage, thereby shielding computerside circuitry from field-side over-voltage conditions. Further, the 5B37 is mix-and-match and hot-swappable with other 5B Series modules, so can be inserted or removed from any socket in the same backplane without disrupting system power. A series output switch eliminates the need for external multiplexing in many applications. The switch is turned on by an active-low enable input. If the switch is to be on at all times, the enable-input should be grounded to power common as it is on the 5B01 and 5B08 backplanes.. A chopper-stabilized input amplifier provides low drift and stable gain. At the amplifier input a stable, laser-trimmed zeroscale input voltage is subtracted from the input signal to set the zero-scale value. For user convenience, the zero can be . . Figure 2 Rev. 0 | Page 2 of 8 5B37 5B37 Models Available Model Input Type Input Range Output Range 5B37-J-01 Type J -100°C to +760°C (-148°F to +1400°F) 0 V to +5 V 5B37-K-02 Type K -100°C to +1350°C (-148°F to +2462°F) 0 V to +5 V 5B37-T-03 Type T -100°C to +400°C (-148°F to +752°F) 0 V to +5 V 5B37-E-04 Type E 0°C to +900°C (+32°F to +1652°F) 0 V to +5 V 5B37-R-05 Type R 0°C to +1750°C (+32°F to +3182°F) 0 V to +5 V 5B37-S-05 Type S 0°C to +1750°C (+32°F to +3182°F) 0 V to +5 V 5B37-B-06 Type B 0°C to +1800°C (+32°F to +3272°F) 0 V to +5 V 5B37-N-08 Type N 0°C to +1300°C (+32°F to +2372°F) 0 V to +5 V 5B37-Custom Type J, K, T, E, R, S, B, N, C * * * Custom Input/Output ranges are available. Refer to configuration guide. 5B37 Specifications (typical @ +25°C and Vs = +5 V dc) Description Model 5B37 Input Ranges Standard Ranges Refer to Model Table Custom Ranges Output Range (RL > 50 kΩ) ±5 mV to ±500 mV 4 -5 V to +5 V or 0 to +5 V Accuracy2 Initial @ +25°C ±0.05% Span ±10 µV RTI ±0.05% of Vz1 +CJC Sensor Error Nonlinearity ±0.02% Span Input Offset vs. Temperature ±1 µV/°C Output Offset vs. Temperature ±20 µV/°C Gain vs. Temperature ±0.0025% of Reading/°C Cold Junction Compensation Initial Accuracy @ +25°C3 ±0.25°C (±0.75°C, maximum) Accuracy, +5°C to +45°C ±0.5°C (±0.0125°C/°C) Input Bias Current -25 nA Input Resistance Power On 5 MΩ Power Off 40 kΩ Overload 40 kΩ Noise Input, 0.1 Hz to 10 Hz Bandwidth 0.2 µV rms Output, 100 kHz Bandwidth 200 µV rms Rev. 0 | Page 3 of 8 5B37 Bandwidth, -3 dB 4 Hz Output Rise Time, 10% to 90% Span 200 ms Common-Mode Voltage (CMV)4 Input-to-Output, Continuous 1500 V rms, maximum Output-to-Power, Continuous ±3 V, maximum Transient ANSI/IEEE C37.90.1-1989 Common Mode Rejection (CMR) 1 kΩ Source Imbalance, 50/60 Hz 160 dB Normal Mode Rejection (NMR), 50/60 Hz 60 dB Input Protection Continuous 240 V rms, maximum Transient ANSI/IEEE C37.90.1-1989 Output Resistance 50 Ω Voltage Output Protection Continuous Short to Ground Output Selection Time 6 µs @ Cload = 0 to 2,000 pF Output Enable Control Max Logic "0" +1 V Min Logic "1" +2.5 V Max Logic "1" +36 V Input Current "0" 0.4 mA Open Input Response Upscale Open Input Response Time 10 seconds Power Supply Voltage +5 V ±5% Power Supply Current 30 mA Power Supply Sensitivity, RTI ±2 µV/% of Vs Mechanical Dimensions 2.275" x 2.375" x 0.595" (57.8 mm x 59.1 mm x 15.1 mm) Environmental Temperature Range Rated Performance -25°C to +85°C Operating -40°C to +85°C Storage -40°C to +85°C Relative Humidity 0 to 93% @ +40°C noncondensing RFI Susceptibility ±0.5% Span error @ 400 MHz, 5 Watt, 3 ft 1 Vz is the nominal input voltage that results in a 0 V output. Includes the combined effects of repeatability, hysteresis, and nonlinearity and assumes RL > 50 kΩ. Loads heavier than 50 kΩ will degrade nonlinearity and gain temperature coefficient. 3 When used with the model AC1361 CJC sensor (see Accessories section), which is provided on each channel of 5B Series backplanes and mounting cards. 4 The output common must be kept within ±3 V of power common. Specifications subject to change without notice. 2 Rev. 0 | Page 4 of 8 5B37 PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS Figure 3 5B37 input Field Connections Table 1. Pin Function Descriptions— Pin No. 1 2 3 4 Description - EXC LO HI n/c Figure 4 . Model 5B Series Module, with pin-out assignments. ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD 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. Rev. 0 | Page 5 of 8 5B37 OUTLINE DIMENSIONS Figure 5. Outline Dimensions Rev. 0 | Page 6 of 8 5B37 NOTES Rev. 0 | Page 7 of 8 5B37 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective companies. D05098-0-9/04(0) Rev. 0 | Page 8 of 8