7B37 ISOLATED, THERMOCOUPLE INPUT




Functional Description

7B37-J-01-1 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 V DC 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.

Inside the 7B37 Series Module

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 Ω) signal is available at the output to drive loads to 2 kΩ minimum.



7B37 FBD

 

Input Types

Thermocouples J, K, T, E, R, S, B

Output Options

+1 V to +5 V

0 V to +10 V

 
7B37 FCD

Figure 2. 7B37 Input Field Connections



7B37 Models Available
  Model Input Type Input Range Output Range
Order Now 7B37-J-01-1 Type J -100°C to +100°C (-148°F to +1400°F) +1 V to +5 V
Order Now 7B37-J-01-2 Type J -100°C to +100°C (-148°F to +1400°F) 0 V to +10 V
Order Now 7B37-J-10-1 Type J 0°C to +200°C (+32°F to +392°F) +1 V to +5 V
Order Now 7B37-J-10-2 Type J 0°C to +200°C (+32°F to +392°F) 0 V to +10 V
Order Now 7B37-J-11-1 Type J 0°C to +400°C (+32°F to +752°F) +1 V to +5 V
Order Now 7B37-J-11-2 Type J 0°C to +400°C (+32°F to +752°F) 0 V to +10 V
Order Now 7B37-J-12-1 Type J 0°C to +600°C (+32°F to +1112°F) +1 V to +5 V
Order Now 7B37-J-12-2 Type J 0°C to +600°C (+32°F to +1112°F) 0 V to +10 V
Order Now 7B37-J-13-1 Type J +300°C to +600°C (+572°F to +1112°F) +1 V to +5 V
Order Now 7B37-J-13-2 Type J +300°C to +600°C (+572°F to +1112°F) 0 V to +10 V
Order Now 7B37-K-02-1 Type K -100°C to +1350°C (-148°F to +2462°F) +1 V to +5 V
Order Now 7B37-K-02-2 Type K -100°C to +1350°C (-148°F to +2462°F) 0 V to +10 V
Order Now 7B37-K-20-1 Type K 0°C to +300°C (+32°F to +572°F) +1 V to +5 V
Order Now 7B37-K-20-2 Type K 0°C to +300°C (+32°F to +572°F) 0 V to +10 V
Order Now 7B37-K-21-1 Type K 0°C to +600°C (+32°F to +1112°F) +1 V to +5 V
Order Now 7B37-K-21-2 Type K 0°C to +600°C (+32°F to +1112°F) 0 V to +10 V
Order Now 7B37-K-22-1 Type K 0°C to +1200°C (+32°F to +2192°F) +1 V to +5 V
Order Now 7B37-K-22-2 Type K 0°C to +1200°C (+32°F to +2192°F) 0 V to +10 V
Order Now 7B37-K-23-1 Type K +600°C to +1200°C (-148°F to +1400°F) +1 V to +5 V
Order Now 7B37-K-23-2 Type K +600°C to +1200°C (-148°F to +1400°F) 0 V to +10 V
Order Now 7B37-T-03-1 Type T -100°C to +400°C (-148°F to +752°F) +1 V to +5 V
Order Now 7B37-T-03-1 Type T -100°C to +400°C (-148°F to +752°F) 0 V to +10 V
Order Now 7B37-E-04-1 Type E 0°C to +900°C (+32°F to +1652°F) +1 V to +5 V
Order Now 7B37-E-04-2 Type E 0°C to +900°C (+32°F to +1652°F) 0 V to +10 V
Order Now 7B37-R-05-1 Type R 0°C to +1750°C (+32°F to +3182°F) +1 V to +5 V
Order Now 7B37-R-05-2 Type R 0°C to +1750°C (+32°F to +3182°F) 0 V to +10 V
Order Now 7B37-S-06-1 Type S 0°C to +1750°C (+32°F to +3182°F) +1 V to +5 V
Order Now 7B37-S-06-2 Type S 0°C to +1750°C (+32°F to +3182°F) 0 V to +10 V
Order Now 7B37-B-07-1 Type B 0°C to +1800°C (+32°F to +3272°F) +1 V to +5 V
Order Now 7B37-B-07-2 Type B 0°C to +1800°C (+32°F to +3272°F) 0 V to +10 V


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 (RL > 2 kΩ) +1 V to +5 V or 0 V to +10 V
Accuracy1
Initial @ +25°C ±0.01% Span (±0.1% Span, maximum)
Nonlinearity2 ±0.02% Span, maximum
Input Offset vs. Temperature ±0.5 µV/°C
Zero Suppression vs. Temperature ±0.005% (Vz)3/°C
Span vs. Temperature ±35 ppm/°C
Output Offset vs. Temperature ±0.002% Span/°C
Cold Junction Compensation
Accuracy4, over +5°C to +45°C ambient ±1.0°C
Input Bias Current +25 nA
Input Resistance
Power ON 10 MΩ
Power OFF 30 kΩ, 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 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)
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 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.
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.
沪ICP备09046653号
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