Dataq DI-725/E, Руководство пользователя

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DI–720/DI–722/DI–730 Series User Manual
Accessories
79
DI-5B32 Analog Current Input Modules
Each DI-5B32 current input module provides a single channel of analog input which is filtered, isolated, amplified,
and converted to a high level analog voltage output (see block diagram). This voltage output is logic switch con-
trolled, which allows these modules to share a common analog bus without the requirement of external multiplexers.
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.
A precision 20
Ω
current conversion resistor is supplied with the DI-5B32 module (see block diagram for installation
details).
Signal filtering is accomplished with a six-pole filter which provides 95dB of normal-mode rejection at 60Hz and
90dB at 50Hz. Two poles of this filter are on the field side of the isolation barrier, and the other four are on the com-
puter side.
After the initial field-side filtering, the input signal is chopped by a proprietary chopper circuit. Isolation is provided
by transformer coupling, again using a proprietary technique to suppress transmission of common mode spikes or
surges. The module is powered from +5VDC, ±5%.
A special input circuit on the DI-5B32 modules provides protection against accidental connection of power-line volt-
ages up to 240VAC.
Ordering Information
MODEL INPUT RANGE OUTPUT RANGE
DI-5B32-01 4mA to 20mA 0V to +5V
DI-5B32-02 0mA to 20mA 0V to +5V