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7B37中文资料

Isolated, Thermocouple Input

7B37

Rev. 0

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One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700

FEATURES

Interfaces, amplifies, and filters input voltages from a J, K, T, E, R, S, or B-type thermocouple.

Module provides a precision output of either +1 V to +5 V or 0 V to +10 V, linear with temperature.

High accuracy internal cold junction compensation. All 7B37 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 -40o C to +85o C 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. 7B37 Functional Block Diagram

The modules feature a maximum nonlinearity of +0.02% and are factory calibrated to guarantee a maximum accuracy specification of +0.1%.

The 7B Series offers up to 1500 V rms continuous common mode voltage isolation and 120 V rms of field wiring input protection. The power supplies necessary to drive each of the individual module’s input circuitry are internally isolated,

enabling the 7B Series modules to offer true channel-to-channel isolation of the input signals.

The modules directly accept analog signals from

thermocouples, RTDs, current loop powered transmitters, and other process control signals. The 7B Series modules amplify, linearize, isolate, protect and convert the transducer output signals to standardized analog inputs for high-level analog I/O subsystems. The 7B Series Subsystem consists of 19-inch rack-compatible hardware (model AC 1363), with universal mounting backplane and a family of plug-in (up to 16 per

backplane) input and output signal conditioning modules. Four-, eight-, and sixteen-channel backplanes are available. Each backplane incorporates screw terminals for easy power connections and field wiring, and includes a 25-pin D-type connector for interfacing the high-level single-ended voltage outputs to the user’s equipment. Gold-plated sockets are provided on each channel of the backplane to ensure the reliability of each module’s electrical connection.

7B37

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GENERAL DESCRIPTION

The 7B37 is a single-channel signal conditioning module that interfaces, amplifies and filters input voltages from a J, K, T, E, R, S, or B-type thermocouple and provides an isolated and

protected precision output of either +1 V to +5 V or 0 V to +10 V , linear with input voltage. High accuracy internal cold

junction compensation and a predictable upscale open circuit indication provide a complete signal conditioning solution. To accurately measure low level signals in electrically noisy environments, 1500 V rms of galvanic transformer-based isolation with a common mode rejection (CMR) of 160 dB @ 50/60 Hz and a normal mode rejection (NMR) of 60 dB @ 50/60 Hz are provided. Rated to operate with a nominal +24 VDC supply, Model 7B37 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 7b37 are fully protected up to 120 V rms line voltages. A one-pole 3 Hz filter preconditions the thermocouple signal prior to amplification, provided by a low drift input amplifier. Cold junction compensation (CJC) is implemented using a thermistor temperature sensor embedded under the input screw terminal block on a 7B Series backplane. A voltage reference source acts to offset the thermocouple signal in accordance with the specified lower bound on the

input temperature range. A current source provides the upscale open circuit indication. Amplitude modulation is used to

implement transformer isolation (1500 V rms input-to-output and power). Isolated front-end circuitry power is supplied by a DC/DC converter. The output section contains a demodulator, a two-pole low pass filter (-3 dB @ 3Hz), a buffer amplifier and a power oscillator. The two-pole output filter and subsequent buffer ensures that a low noise, low impedance (<1?) signal is available at the output to drive loads to 2k ? minimum.

Figure 2

7B37

7B37 Models Available

Model Input Type Input Range Output Range

7B37-J-01-1Type J -100°C to +100°C (-148°F to +1400°F) +1 V to +5 V

7B37-J-01-2Type J -100°C to +100°C (-148°F to +1400°F) 0 V to +10 V

7B37-J-10-1Type J 0°C to +200°C (+32°F to +392°F) +1 V to +5 V

7B37-J-10-2Type J 0°C to +200°C (+32°F to +392°F) 0 V to +10 V

7B37-J-11-1Type J 0°C to +400°C (+32°F to +752°F) +1 V to +5 V

7B37-J-11-2Type J 0°C to +400°C (+32°F to +752°F) 0 V to +10 V

7B37-J-12-1Type J 0°C to +600°C (+32°F to +1112°F) +1 V to +5 V

7B37-J-12-2Type J 0°C to +600°C (+32°F to +1112°F) 0 V to +10 V

7B37-J-13-1Type J +300°C to +600°C (+572°F to +1112°F) +1 V to +5 V

7B37-J-13-2Type J +300°C to +600°C (+572°F to +1112°F) 0 V to +10 V

7B37-K-02-1Type K -100°C to +1350°C (-148°F to +2462°F) +1 V to +5 V

7B37-K-02-2Type K -100°C to +1350°C (-148°F to +2462°F) 0 V to +10 V

7B37-K-20-1Type K 0°C to +300°C (+32°F to +572°F) +1 V to +5 V

7B37-K-20-2Type K 0°C to +300°C (+32°F to +572°F) 0 V to +10 V

7B37-K-21-1Type K 0°C to +600°C (+32°F to +1112°F) +1 V to +5 V

7B37-K-21-2Type K 0°C to +600°C (+32°F to +1112°F) 0 V to +10 V

7B37-K-22-1Type K 0°C to +1200°C (+32°F to +2192°F) +1 V to +5 V

7B37-K-22-2Type K 0°C to +1200°C (+32°F to +2192°F) 0 V to +10 V

7B37-K-23-1Type K +600°C to +1200°C (-148°F to +1400°F) +1 V to +5 V

7B37-K-23-2Type K +600°C to +1200°C (-148°F to +1400°F) 0 V to +10 V

7B37-T-03-1Type T -100°C to +400°C (-148°F to +752°F) +1 V to +5 V

7B37-T-03-1Type T -100°C to +400°C (-148°F to +752°F) 0 V to +10 V

7B37-E-04-1Type E 0°C to +900°C (+32°F to +1652°F) +1 V to +5 V

7B37-E-04-2Type E 0°C to +900°C (+32°F to +1652°F) 0 V to +10 V

7B37-R-05-1Type R 0°C to +1750°C (+32°F to +3182°F) +1 V to +5 V

7B37-R-05-2Type R 0°C to +1750°C (+32°F to +3182°F) 0 V to +10 V

7B37-S-06-1Type S 0°C to +1750°C (+32°F to +3182°F) +1 V to +5 V

7B37-S-06-2Type S 0°C to +1750°C (+32°F to +3182°F) 0 V to +10 V

7B37-B-07-1Type B 0°C to +1800°C (+32°F to +3272°F) +1 V to +5 V

7B37-B-07-2Type B 0°C to +1800°C (+32°F to +3272°F) 0 V to +10 V

Rev. 0 | Page 3 of 8

7B37

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7B37 Specifications

(typical @ +23°C ±5°C and Vs = +24 V dc)

Description Model 7B37

Input Range1 Thermocouple Types

J, K, T, E, R, S, B Standard Temperature Ranges Refer to Model Table Custom Ranges

Not Available*

Output Range Options (R L > 2 k ?)

+1 V to +5 V or 0 V to +10 V Accuracy 1

Initial @ +25°C ±0.01% Span (±0.1% Span, maximum) Nonlinearity 2

±0.02% Span, maximum Input Offset vs. Temperature ±0.5 μV/°C Zero Suppression vs. Temperature ±0.005% (V z )3/°C Span vs. Temperature ±35 ppm/°C Output Offset vs. Temperature

±0.002% Span/°C

Cold Junction Compensation

Accuracy 4, over +5°C to +45°C ambient ±1.0°C Input Bias Current

+25 nA

Input Resistance

Power ON 10 M ?

Power OFF

30 k ?, minimum Output Noise

5 MHz Bandwidth

6 mV peak 10 Hz to 100 kHz Bandwidth 0.4 mV rms 0.1 Hz to 10 Hz Bandwidth 0.6 μV peak Bandwidth, -3 dB

3 Hz Output Rise Time, 10% to 90% Span

150 ms

Common-Mode Voltage (CMV)

Input-to-Output and Power

1500 V rms, continuous

Common Mode Rejection (CMR)

Input-to-Output and Power @ 50/60 Hz 160 dB Normal Mode Rejection @ 50/60 Hz 60 dB

Input Protection

120 V rms, continuous

±35 V dc, continuous Input Transient Protection

ANSI/IEEE C376.90.1-1989 IEEE-STD 472 IEC 255-4, Class II Output Resistance < 1 ?

Voltage Output Protection

Continuous Short to Ground

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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)

Weight 60 grams

Environmental

Temperature Range Operating -40°C to +85°C Storage

-40°C to +85°C

Relative Humidity, 24 hours 0 to 90% @ +60°C non-condensing 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.

1Includes the combined effects of repeatability, hysteresis, and nonlinearity. 2Nonlinearity is calculated using best-fit straight line method. 3Vz is the nominal input voltage that results in a 0 V output.

4When used with the CJC temperature sensor provided on each channel of 7B Series backplanes. Specifications subject to change without notice.

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PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS

Figure 3 7B37 Input Field Connections

Table 1. Pin Function Descriptions—

No. Input Module Function Output Module Function 0 SENSOR INPUT NOT USED 1 INPUT HIGH OUTPUT HIGH 2 INPUT LOW OUTPUT LOW

3 POWER SUPPLY (DC)

POWER SUPPLY (DC) 4 OUTPUT

V OLTAGE INPUT V OLTAGE 5 OUTPUT & POWER

COMMON

INPUT AND POWER COMMON

Figure 4 . Model 7B 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.

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OUTLINE DIMENSIONS

Figure 5. Outline Dimensions

7B37

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NOTES