DI-500/510 Series and DI-750/760 Series Hardware Manual
5B Modules
27
DI-5B33 Isolated True RMS Input Modules
DESCRIPTION
Each DI-5B33 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 (see block diagram).
The DI-5B 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. Connec-
tion, with series load, is between Pin 20 (+) and Pin 19 (-).
Ordering Information
MODEL
INPUT RANGE
OUTPUT RANGE
DI-5B33-01
100mV
0V to +5V
DI-5B33-02
1V
0V to +5V
DI-5B33-03
10V
0V to +5V
DI-5B33-04
150V
0V to +5V
DI-5B33-05
300V
0V to +5V
Isolation Barrier
+PWR
PWR
+IN
+OUT
IN
OUT
Power
Oscillator
+V
-V
+Vf
-Vf
s
s
AC Source
**
**
Rconv*
Surge Suppression
and Protection
Pre-Amp,
Conversion
Isolated
Field-Side
Power
Isolated
System-Side
Power
LPF
Iso-Chopper II
Amplifier
Pat. Pending
TM
1
2
3
4
5
6
7
8
F r e e D a t a s h e e t h t t p : / / w w w . d a t a s h e e t 4 u . c o m /
