DATAFORTH
A Burr-Brown Company
®
48
Call 800-444-7644
For Information and Assistance
SCM5B33
Isolated True RMS Input Modules
FEATURES
INTERFACES RMS VOLTAGE (0 – 300V) OR RMS CURRENT (0 – 5A)
DESIGNED FOR STANDARD OPERATION WITH FREQUENCIES OF
45HZ TO 1000HZ (EXTENDED RANGE TO 20Khz)
COMPATIBLE WITH STANDARD CURRENT AND POTENTIAL
TRANSFORMERS
INDUSTRY STANDARD OUTPUTS OF EITHER 0-1MA, 0-20mA,
4-20MA, 0-5V OR 0-10VDC
±0.25% FACTORY CALIBRATED ACCURACY (ACCURACY CLASS
0.2)
1500 VRMS CONTINUOUS TRANSFORMER BASED ISOLATION
INPUT OVERLOAD PROTECTED TO 480V MAX (PEAK AC & DC) OR
10A RMS CONTINUOUS
ANSI/IEEE C37.90.1-1989 TRANSIENT PROTECTION
REGULATORY COMPLIANCE (TO BE DETERMINED)
DESCRIPTION
Each SCM5B33 True RMS input module provides a single channel of AC
input which is converted to its True RMS dc value, filtered, isolated,
amplified, and converted to a standard process voltage or current output
(Figure 1).
The SCM5B modules are designed with a completely isolated computer side
circuit which can be floated to ±50V from Power Common, pin 16. This
complete isolation means that no connection is required between I/O
Common and Power Common for proper operation of the output switch. If
desired, the output switch can be turned on continuously by simply connecting
pin 22, the Read-Enable pin to I/O Common, pin 19.
The field voltage or current input signal is processed through a pre-amplifier
and RMS converter on the field side of the isolation barrier. The converted dc
signal is then chopped by a proprietary chopper circuit and transferred across
the transformer isolation barrier, suppressing transmission of common
mode spikes and surges. The computer side circuitry reconstructs, filters and
converts the signal to industry standard outputs. Modules are powered from
+5VDC, ±5%.
For current output models an external loop supply is required having a
compliance voltage of 14 to 48VDC. Connection, with series load, is between
Pin 20 (+) and Pin 19 (-).
FIGURE 1. SCM5B33 Block Diagram.
+InAC Source
–In
**
**
**
–EXC
Backpanel
Term Block
6
5
3
Surge
Suppression
and
Protection
Pre-Amp,
Conversion
*
* Current Input Models Only
Add Jumpers for Current Input Modules
(provided with SCM5B33-06, 07)
Isolated
Field-Side
Power
4
3
2
1
+EXC
–V
+V
I
IN
4
–V
LPF
+V
Power
Oscillator
Isolated
Computer-Side
Power
V
OUT or
I
OUT
20
22
I/O Common
RD EN\
+5V
17
16 Power Common
19
Isochopper™
Amplifier
Pat Pending
DATAFORTH
A Burr-Brown Company
®
49 Call 800-444-7644
For Information and Assistance
Input
Signal Range 100mV to 300V rms, 0 to 5A rms
Standard Frequency Range 45Hz to 1000Hz
Extended Frequency Range 1kHz to 20kHz
Impedance 1 M ±1% shunted by 100pF (-01 thru -05),
0.10 (-06), 0.025 (-07)
Coupling AC
Protection(1)
Continuous (-01 thru -05) 300V rms
Continuous (-06 thru -07) 10A rms
Transient (-01 thru -05) ANSI/IEEE C37.90.1-1989
Transient (-06 thru -07) See note 2
Output
Signal Range 0-5V or 0-10V or 0-1mA or 0-20mA or 4-20mA
Current Limit 1.4mA (0-1mA models), 30mA (0/4-20mA models),
8mA (0-5, 0-10V models)
Voltage Limit ±18V (0-5, 0-10V models)
Resistance 50 (0-5, 0-10V models)
Protection Continuous Short to Ground
Ripple and Noise (100Khz) 0.025% Span rms
Accuracy(3)(4)
Sinusoid
50/60 Hz ±0.25% Span
45Hz to 1kHz ±0.25% Reading Additional Factor
1kHz to 20kHz ±0.75% Reading Additional Factor
Non-Sinusoid
Crest Factor = 1 to 2 ±0.05% Reading Additional Error
Crest Factor = 2 to 3 ±0.15% Reading Additional Error
Crest Factor = 3 to 4 ±0.30% Reading Additional Error
Crest Factor = 4 to 5 ±0.40% Reading Additional Error
Vs. Temperature ±100ppm/°C
Isolation (Common Mode)
Input to Output, Input to Power
Continuous 1500Vrms max
Transient ANSI/IEEE C37.90.1-1989
Output to Power
Continuous 50Vdc max
Rejection (50-60Hz Common Mode) 100dB
Response Time (0 to 99%) <400ms
Output Enable Control
Selection Time 6.0µS @ CLOAD = 0 to 2000pF
Voltage
Max Logic “0” +0.8V
Min / Max Logic “1” +2.4V / +36V
Current, “0,1” 0.5µA
Loop Voltage +7.5Vdc min, +26Vdc max, -40˚C to +85˚C
Load Resistance (maximum) (Loop Voltage - 14) / (Loop Current)
Supply Voltage +5VDC ±5%
Current 120mA
Sensitivity ±200ppm/%
Environmental
Operating Temp. Range -40˚C to +85˚C
Storage Temp. Range -40˚C to +85˚C
Relative Humidity 0 to 90% noncondensing
Emissions EN50081-1, ISM Group 1, Class A (Radiated, Conducted)
Immunity EN50082-1, ISM Group 1, Class A (ESD, RF, EFT)
Dimensions 2.28" x 2.26" x 0.60" (58mm x 57mm x 15mm)
NOTE:
(1) SCM5B33 and SCMPB01, 02, 03, 04, 05, 06, 07, XEV rating only. Backpanels obtained
from other sources may have lower ratings.
(2) For 1 to 25 seconds the max allowable transient current rating is 2500 / (event time). For
less than 1 second, ANSI/IEEE C-37.90.1-1989 applies with a 0.05 load. For greater than
25 seconds, the 10A rms continuous rating applies.
(3) At standard 60Hz factory calibration. Consult factory for calibration at other frequencies.
(4) For 10-100% rated span. Add an additional 0.25% error for 0-10% Span measurements.
Accuracy includes nonlinearity, hysteresis and repeatability but not source or external shunt
inaccuracy (if used).
MODEL INPUT* (rms) OUTPUT* (dc)
SCM5B33-01 0-100mV 0-5V
SCM5B33-02 0-1V 0-5V
SCM5B33-03 0-10V 0-5V
SCM5B33-04 0-150V 0-5V
SCM5B33-05 0-300V 0-5V
SCM5B33-06 0-1A 0-5V
SCM5B33-07 0-5A 0-5V
SCM5B33-01B 0-100mV 0-1mA
SCM5B33-02B 0-1V 0-1mA
SCM5B33-03B 0-10V 0-1mA
SCM5B33-04B 0-150V 0-1mA
SCM5B33-05B 0-300V 0-1mA
SCM5B33-06B 0-1A 0-1mA
SCM5B33-07B 0-5A 0-1mA
SCM5B33-01C 0-100mV 4-20mA
SCM5B33-02C 0-1V 4-20mA
SCM5B33-03C 0-10V 4-20mA
SCM5B33-04C 0-150V 4-20mA
SCM5B33-05C 0-300V 4-20mA
SCM5B33-06C 0-1A 4-20mA
SCM5B33-07C 0-5A 4-20mA
SCM5B33-01D 0-100mV 0-10V
SCM5B33-02D 0-1V 0-10V
SCM5B33-03D 0-10V 0-10V
SCM5B33-04D 0-150V 0-10V
SCM5B33-05D 0-300V 0-10V
SCM5B33-06D 0-1A 0-10V
SCM5B33-07D 0-5A 0-10V
SCM5B33-01E 0-100mV 0-20mA
SCM5B33-02E 0-1V 0-20mA
SCM5B33-03E 0-10V 0-20mA
SCM5B33-04E 0-150V 0-20mA
SCM5B33-05E 0-300V 0-20mA
SCM5B33-06E 0-1A 0-20mA
SCM5B33-07E 0-5A 0-20mA
* Modules can be ordered with other input/output ranges. Consult factory for
ordering details and specifications.
SPECIFICATIONS Typical at TA = +25°C and +5V power.
Module
ORDERING INFORMATION
SCM5B33
SCM5B