DI–4718B Series Hardware Manual
DI-8B Modules
37
DI-8B42 2-Wire Transmitter Interface Modules
Each DI-8B42 module provides power to a current transmitter, then isolates, filters and amplifies the resulting pro-
cess current input signal and provides an analog voltage output.
Current to voltage conversion is accomplished internal to the module to ensure high accuracy.
Signal filtering is accomplished with a three-pole filter optimized for time and frequency response which provides
60dB per decade of normal-mode rejection above 100Hz. One pole of this filter is on the field side of the isolation
barrier for anti-aliasing, and the other two are on the system side.
A special input circuit on the DI-8B42 module provides protection against accidental connection of power-line volt-
ages up to 40VAC. Clamp circuits on the I/O and power terminals protect against harmful transients.
Isolation is provided by optical coupling to suppress transmission of common mode spikes or surges. The module is
powered from +5VDC, ±5%.
Ordering Information
MODEL
INPUT RANGE
OUTPUT RANGE
DI-8B42-01
4mA to 20mA
0V to +5V
DI-8B42-02
4mA to 20mA
+1V to +5V
