124
Call 800-444-7644
For Information and Assistance
DATAFORTH
A Burr-Brown Company
®
SCM7B40/41
Isolated Analog Voltage Input Modules, Wide Bandwidth
FEATURES
● ACCEPTS MILLIVOLT OR VOLTAGE INPUTS
● PROVIDES HIGH LEVEL VOLTAGE OUTPUTS
● 10KHZ BANDWIDTH
● 1500Vrms TRANSFORMER ISOLATION
● ACCURACY, ±0.03% OF SPAN TYPICAL, ±0.1% MAX
● ANSI/IEEE C37.90.1-1989 TRANSIENT PROTECTION
● INPUT PROTECTED TO 120Vrms CONTINUOUS
● EASY DIN RAIL MOUNTING
● CSA CERTIFIED, FM APPROVAL PENDING
● CE COMPLIANT
DESCRIPTION
Each SCM7B40/41 voltage input module accepts one channel of analog
voltage input which is filtered, isolated, amplified, and converted to a high
level analog voltage for output to the process control system.
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.
Fig 1: SCM7B40/41 Block Diagram
LPF
(1 pole)
+
–
XNC
Surge
Suppression
and
Protection
Backpanel
Term Block
dc Supply
Field-Side
–V
+V
V
IN
V
S
LPF
(4 pole)
dc Supply/
Oscillator
Process Control
System-Side
Iso-Chopper II™
Amplifier
Pat Pending
1500V
Isolation Barrier
V
OUT
4
5
3
COM
(14-35V dc)
0
2
1
–
+
DATAFORTH
A Burr-Brown Company
®
125 Call 800-444-7644
For Information and Assistance
Module SCM7B40 SCM7B41
Input
Signal Range -1V to +1V -10V to +40V
Bias Current ±1nA ±0.1nA
Resistance
Normal 50MΩ500kΩ min
Power Off 30kΩ min 500kΩ min
Overload 30kΩ min 500kΩ min
Protection
Continous 120Vrms max *
Transient ANSI/IEEE C37.90.1-1989 *
Output
Signal Range1◆◆
Effective Available Power140mW *
Resistance <1Ω*
Protection Continuous Short-to-Ground *
Voltage/Current Limit ±12V, ±14mA *
CMV (Input-to-Output)
Continuous 1500Vrms max *
Transient ANSI/IEEE C37.90.1-1989 *
CMRR (50 or 60Hz) 110dB 100dB
Accuracy2 ±0.03% Span typical, ±0.1% Span max *
Nonlinearity3±0.01% Span typical, ±0.02% Span max *
Stability (-40C to +85°C)
Gain ±35ppm/°C±55ppm/°C
Input Offset ±0.5µV/°C±5µV/°C
Zero Suppression ±0.005%(Vz)5/°C*
Output Offset ±0.002% Span/°C*
Noise
Peak @ 5MHz B/W 2mV *
RMS @ 10Hz to 100kHz B/W 1mV *
Peak @ 0.1Hz to10Hz B/W 1µV*
Frequency and Time Response
Bandwidth, -3dB 10KHz *
NMR 80dB/decade >10KHz *
Step Response, 90% Span 40µs*
Supply Voltage 14 to 35VDC *
Current112mA *
Sensitivity ±0.0001%/%Vs *
Mechanical Dimensions (H)(W)(D) 2.13" x 1.705" x 0.605" max *
54.1mm x 43.3mm x 15.4mm max *
Environmental
Operating Temperature Range -40°C to +85°C*
Storage Temperature Range -40°C to +85°C*
Relative Humidity 0 to 90% noncondensing *
Emmissions EN50081-1, ISM Group 1, Class A (Radiated, Conducted) *
Immunity EN50082-1, ISM Group 1, Class A (ESD, RF, EFT) *
NOTES
* Specification same as preceding model.
1 Output Range and Supply Current specifications are based on minimum output load resistance.
Minimum output load resistance is calculated by VOUT2/PE, where PE is the Output Effective Available
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.
SPECIFICATIONS Typical at 25°C and +24VDC
◆OUTPUT RANGES AVAILABLE
OUTPUT RANGE PART NUMBER MODIFIER EXAMPLE
+1 to +5V (none) SCM7B40-02
0 to +5V A SCM7B40-02A
0 to +10V D SCM7B40-02D
SCM7B
ORDERING INFORMATION
MODEL INPUT RANGE
SCM7B40-02 0 to +100mV
SCM7B40-03 0 to +1V
SCM7B40-07 ±100mV
SCM7B40-08 ±1V
SCM7B41-01 0 to +10V
SCM7B41-02 ±5V
SCM7B41-03 ±10V
SCM7B41-04 0 to +5V
SCM7B41-05 0 to +20V
SCM7B41-06 0 to +40V
