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SCM7B37K-20A

Isolated Thermocouple Input Module

SCM7B37K-20A
Isolated Thermocouple Input Module

Product Availability:
  • Usually stock to 3-5 weeks. Contact Customer Service for current lead times.

Description

SCM7B37 non-linearized modules accept a single channel of input from Type J, K, T, E, R, S, or B thermocouples. The signal is filtered, isolated, amplified, and converted to a high-level analog voltage for output to the process control system.

Cold junction compensation (CJC) is performed using an NTC thermistor (see "Additional SCM7B Part Numbers" section for P/N and AN701 for further information) externally mounted under the field-side terminal block on the backpanel (Figure 1). Open thermocouple detection is upscale using a 30nA current source in the input circuitry.

These modules incorporate a five-pole filtering approach to maximize both time and frequency response by taking advantage of both Thomson (Bessel) and Butterworth characteristics. One pole of the filter is on the field side of the isolation barrier; four are on the process control system side.

After the initial field-side filtering, the input signal is chopped by a proprietary chopper circuit and transferred across the transformer isolation barrier, suppressing transmission of common mode spikes and surges. The signal is then reconstructed and filtered for process control system output.

Modules accept a wide 14 - 35VDC power supply range (+24VDC nominal). Their compact packages (2.13"x1.705"x0.605" max) save space and are ideal for high channel density applications. They are designed for easy DIN rail mounting using any of the "-DIN" backpanels.

Features

  • Interfaces to Type J, K, T, E, R, S, and B Thermocouples
  • Provides High-Level Voltage Outputs
  • 1500Vrms Transformer Isolation
  • Accuracy, ±0.03% of Span Typical, ±0.1% Max
  • ANSI/IEEE C37.90.1 Transient Protection
  • Input Protected to 120Vrms Continuous
  • Noise, 500µV Peak (5MHz), 250µV RMS (100kHz)
  • CMRR, 160dB
  • NMR, up to 85dB
  • Easy DIN Rail Mounting
  • CSA Certified, FM Approved
  • CE and ATEX Compliant

Block Diagram

Certifications

Specifications

  • Thermocouple Type K
  • Output Range 0 to +5 V
  • Input Temperature Range 0 to 300 °C
  • Mechanical Format Modular plug-in-board
  • Isolation Voltage 1500 Vrms
  • Isolation Type Transformer 2-way
  • Accuracy ±0.03% (0.09°C) typical, ±0.1% (0.30°C) max
  • Supply Voltage 14 to 35 VDC
  • Input Voltage Withstand 120 Vrms
  • Gain/Offset Adjust N/A
  • Module Bandwidth 3 Hz
  • NMR (60 Hz) Rejection 80/85dB
  • External I-to-V Resistor N/A
  • Output Control Always Enabled
  • Output Resistance < 1 Ohm
  • Dimensions 2.13 x 1.705 x 0.605 inches
  • Interface 5 or 6 pin
  • Customization yes
  • Weight 48 grams (1.69 ounces)

Accessories

PWR-PS5R120W
Power Supply, DIN Rail Mount, 85-264 VAC 47-63 Hz In, 24 VDC 5.0 A Out View
PWR-PS5R15W
Power Supply, DIN Rail Mount, 85-264 VAC 47-63 Hz In, 24 VDC 0.65 A Out View
PWR-PS5R30W
Power Supply, DIN Rail Mount, 85-264 VAC 47-63 Hz In, 24 VDC 1.3 A Out View
PWR-PS5R60W
Power Supply, DIN Rail Mount, 85-264 VAC 47-63 Hz In, 24 VDC 2.5 A Out View
PWR-PS5R7W
Power Supply, DIN Rail Mount, 85-264 VAC 47-63 Hz In, 24 VDC 0.3 A Out View
SCM7BP01
1 channel backpanel View
SCM7BP01-DIN
1 channel backpanel (DIN) View
SCM7BP02
2 channel backpanel View
SCM7BP02-DIN
2 channel backpanel (DIN) View
SCM7BP04
4 channel backpanel View
SCM7BP04-DIN
4 channel backpanel (DIN) View
SCM7BP08
8 channel backpanel View
SCM7BP08-DIN
8 channel backpanel (DIN) View
SCM7BP16
16 channel backpanel View
SCM7BP16-DIN
16 channel backpanel (DIN) View
SCM7B-PROTO
SCM7B breadboard kit View
SCM7BPT
Non-isolated signal pass thru module View
SCM7BXCA01
1 meter system adapter cable (DB25F to 26M) View
SCM7BXCA02
2 meter system interface cable (DB25F to DB25F) View
SCM7BXEV
1 channel evaluation backpanel View
SCM7BXR1
250 Ohm current conversion resistor View
SCMXBE
DIN rail base element without snap foot View
SCMXBEFE
DIN rail base element with snap foot View
SCMXCA006-01
System interface cable for backpanels, 1 meter length View
SCMXCA006-02
System interface cable for backpanels, 2 meter length View
SCMXDB37F25BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXDB37F27BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXDB37F28BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXDB37F5BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXDB37F7BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXDB37F8BP00
Third Party DAQ Front-Ending Adapter for Dataforth Backpanels View
SCMXIF
Ribbon cable to screw terminal interface board View
SCMXIF-DIN
Ribbon cable to screw terminal interface board, DIN mount View
SCMXRAIL1-1.0
DIN EN 50022-35 x 7.5 (slotted steel), 1 meter length View
SCMXRAIL1-2.0
DIN EN 50022-35 x 7.5 (slotted steel), 2 meter length View
SCMXRAIL2-01
DIN EN 50035-G32 (slotted steel), 1 meter length View
SCMXRAIL2-02
DIN EN 50035-G32 (slotted steel), 2 meter length View
SCMXRAIL3-01
DIN EN 50022-35 x 15 (slotted steel), 1 meter length View
SCMXRAIL3-02
DIN EN 50022-35 x 15 (slotted steel), 2 meter length View
SCMXRK-002
19 inch metal rack for mounting analog backpanels View
SCMXSE
DIN rail side element View
SCMXVS
DIN rail connection pins View

Competitive Cross-Reference

  • The SCM7B37K-20A equals the Analog Devices NOT AVAILABLE. For specific performance comparison, please review both datasheets.
View Dataforth cross-reference data.
The information available through this competitive cross reference guide are based upon product catalog information obtained from a variety of sources. The competitive cross reference information is being provided to you free of charge for your use. While Dataforth Corp has used reasonable efforts to ensure data accuracy, Dataforth Corp does not guarantee that it is error-free, nor does Dataforth Corp make any other representation, warranty or guarantee that the information is accurate, correct, reliable or up-to-date. Dataforth Corp expressly disclaims all implied warranties regarding this information, including but not limited to any implied warranties of merchantability or fitness for a particular purpose.

This information is provided only as a convenience on an "as is" basis and Dataforth Corp. or its representatives or distributors are not responsible for any incorrect, inaccurate, or incomplete information. You are solely responsible for (1) selecting the appropriate Dataforth products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable standards, and any other safety, security, or other requirements.

FAQ

Can Dataforth analog modules be used in high vibration environments? If so, what type of testing or certification was completed?
SCM5B, SCM7B, 8B SensorLex, and DSCA modules are well suited for use in high vibration environments. These modules and their associated accessories have undergone testing for random vibration, shock, and swept sine wave vibration. Details of each of these testing methods are provided below: Random Vibration (Operating): ○ MIL-STD 202G, Method 214A, Condition 1 - Frequency Range: 50-2000Hz, flat spectrum - Vibration Intensity: 7.56 Grms - Duration: 10min/axis (X, Y, Z) Shock (Operating): ○ MIL-STD-810F, Method 516.5 - Pulse Shape: Sawtooth - Test Level: 30G - Duration 11ms - Orientation: +/-X, +/-Y, +/-Z Swept Sine Vibration (Operating) ○ MIL-STD-810G, Method 514.6, modified - Frequency Range: 10-2000Hz - Vibration Intensity: 5Gp-p - Sweep Rate: 1 octave/min - Orientation: X, Y, Z Declaration of conformity for the above-listed tests can be provided upon customer request. Please contact customer service if a copy of the declaration is needed.
Due to resource constraints on my computer, I'm unable to open the three dimensional CAD models provided on your website. Does Dataforth provide two demensional CAD models for download as well?
Two dimensional CAD models can be generated upon customer request. Please contact Customer Service for assistance.
What does it mean when an input module has for example a 3kHz bandwidth?
A 3kHz bandwidth on an input module means it can accept voltages from DC to 3000Hz. Any frequency higher than that and the signal will start to be attenuated by the filter at the input.
Can SCM5B modules be hot swapped?
Not just SCM5B modules, but any signal conditioning module series and MAQ20 I/O modules can be hot swapped. A minimal amount of signal settling time may result, but there will be no damage to the device.
What does "Response time, 90% span" mean on the datasheet for my module?
Normally, a response time figure refers to how quickly a module's output can "respond" to a change in the input signal. "Response time, 90% span" refers to how fast a module can adjust its output when a step signal is applied at the input, where the magnitude of this step input is 90% of the input span of the module.
If a thermocouple is soldered to a lead that has current running through it, how do you avoid affecting the thermocouple signal and subsequent measurement?
The thermocouples must be isolated so current does not come from the circuit under test and run through them. SCM5B, SCM7B, 8B, DSCA, DSCT, MAQ20 all offer the required isolation.
Where can I find the MTBF of my module?
Information on MTBF for SCM5B, SCM7B, 8B and DSCA is available on our website. Please see application note AN802 for more details. Application notes can be found under the "Literature" tab on the top navigation bar.
Is the calibration of Dataforth modules traceable to NIST standards?
Yes, calibration of Dataforth modules is traceable to NIST standards.
If I purchase a backplane with no CJC, will I still be able to use modules that require the CJC enable jumper to be installed?
Yes. Backplanes with no CJC will still come with the CJC enable installed on the backplane.
How does the load resistance of a module affect the noise at the output?
Noise at the output of a module is independent of load resistance.
How do I convert an RMS voltage to its corresponding peak voltage?
To convert an RMS voltage to its corresponding peak voltage, you simply take the RMS voltage value and multiply it by the square root of 2, or roughly 1.414. For example, 1500Vrms corresponds to a peak voltage of 1500 * 1.414 = 2121 Vp
If the input range of my signal conditioner is -1V to +1V and the output range is 0 to 10V, does this mean that it ignores polarity?
A signal conditioner with these I/O ranges does not mean that the module ignores the polarity of your voltage input. The output of voltage input modules are scaled linearly, meaning an input of -1V would correspond to an output of 0V, an input of 0V would correspond to an output of 5V, an input of +1V would correspond to an output of 10V, and so on.
Is the SCMXPRT-003 DIN rail mountable?
The SCMXPRT-001 has an option for DIN rail mounting (part number: SCMXPRT-001D) but the SCMXPRT-003 does not. Instead, it can be mounted on the SCMXRK-002 which is a 19 inch metal rack for mounting the SCMXPRT-003 as well as various Dataforth backpanels and the SCMXIF interface board.
Analog Devices announced a last time buy and discontinuance of their signal conditioning modules. Can I replace them with Dataforth signal conditioning modules?
Yes, in general, Dataforth signal conditioning modules are a direct replacement for all Analog Devices signal conditioning modules. e.g. "SCM5B35-xx: Linearized 4-Wire RTD Input Modules" will replace Analog Devices "5B35: Isolated 4 Wire RTD Input Signal Conditioning Module". Please note that Dataforth signal conditioning modules are RoHS II compliant.
Can Dataforth provide calibration reports for modules I purchased?
Yes we can provide calibration reports for the modules that you purchased. You can either a) visit https://www.dataforth.com/TestDataReport.aspx to search for Test Report Datasheets by Serial Number or b) you can send us a list of model numbers and their serial numbers to support@dataforth.com

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