Impulse SCM7B22 User Manual

Isolated Process Control Signal Conditioning Products

SCM7B22

Isolated Bipolar Voltage Output Modules

Description

SCM7B22 voltage output modules accept input signals in the ±10V range from

the process control system. The signal is isolated, buffered, and filtered to

provide a unity gain field voltage output (Figure 1).

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 process control system

side of the isolation barrier; four are on the field side.

After the initial process control system-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 field-side output.

Modules accept a wide 19 - 29VDC 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.

SCM7B

▲

Features

 Accepts High Level Input to ±10V

 Provides High Level Output to ±10V

 1500Vrms Transformer Isolation

 Accuracy, ±0.03% of Span Typical,

±0.1% Max

 ANSI/IEEE C37.90.1 Transient Protection

 Output Protected to 120Vrms Continuous

 Input Protected to ±35VDC

 Noise, 2mV Peak (5MHz), 1mV RMS

(100kHz)

 CMRR, 100dB

 80dB Per Decade of Attenuation

Above 400Hz

 Easy DIN Rail Mounting

 CSA Certified, FM Approved

 CE and ATEX Compliant

Figure 1: SCM7B22 Block Diagram

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For information call 800-444-7644

Isolated Process Control Signal Conditioning Products

SCM7B

Specifications

Module

Output

Signal Range

Effective Available Power

(1)

Typical at 25°C and +24VDC

(1)

SCM7B22

±10V

20mW

Resistance <1Ω

Protection

Continuous 120Vrms

Transient ANSI/IEEE C37.90.1

Voltage/Current Limit ±12.5V, ±40mA

Input

Signal Range ±10V

Bias Current ±0.5nA

Resistance 2MΩ min

Protection ±35Vdc (no damage)

CMV (Input-to-Output)

Continuous 1500Vrms

Transient ANSI/IEEE C37.90.1

CMRR (50 or 60Hz) 100dB

(2)

Accuracy

Nonlinearity

(3)

±0.03% Span typical,

±0.1% Span max

±0.01% Span typical,

±0.02% Span max

Stability (-40°C to +85°C)

Gain ±35ppm/°C

Output Offset ±0.001% Span/°C

Noise

Peak at 5MHz B/W 2mV

RMS at 10Hz to 100kHz B/W 1mV

Peak at 0.1Hz to 10Hz B/W 10µV RTI

Frequency and Time Response

Bandwidth, -3dB 400Hz

NMR (-3dB at 400Hz) 80dB per decade above 400Hz

Step Response, 90% Span 1m s

Supply Voltage 19 to 29VDC

(1)

Current

Sensitivity ±0.0001%/%V

16mA

S

Mechanical Dimensions 2.13" x 1.705" x 0.605" max

(h)(w)(d) 54.1mm x 43.3mm x 15.4mm max

Environmental

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

ATEX Group II, Category 3 -20°C to +40°C

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

Relative Humidity 0 to 95% noncondensing

Emissions EN61000-6-4 ISM, Group 1

Radiated, Conducted Class A

Immunity EN61000-6-2 ISM, Group 1

R F Performance A ±0.5% Span Error

ESD, EFT, Surge, Voltage Dips Performance B

NOTES:

(1) Output Range and Supply Current specifications are based on minimum output load resistance.

Minimum output load resistance is calculated by V

Power that guarantees output range, accuracy, and linearity specifications.

(2) Accuracy includes the effects of repeatability, hysteresis, and linearity.

(3) Nonlinearity is calculated using the best-fit straight line method.

2

/PE, where PE is the Output Effective Available

OUT

Ordering Information

Model Input Range Output Range

SCM7B22 ±10V ±10V

SCM7B

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