Measurement Computing PC104-PDISO8 - Manual (Page 5)

1 INTRODUCTION
1.1 DESCRIPTION
The PC104-PDISO8 has 8-channels of isolated inputs and relay outputs. The board is
designed for sensing and control applications having high voltages.
WARNING!
High voltages will be present on the board when you have
connected high voltage inputs or outputs to the connector.
Use extreme caution! Never handle the board when live signals are
connected to the board via the connector.
The eight outputs are electromechanical relays. Five provide FORM C connections
and three provide normally-open FORM A connection. The relays are controlled by
writing to one 8-bit port. The state of the relay control register may be read back.
The inputs are eight individual, optically-isolated inputs that may be read back as a
single byte. The inputs are not polarity sensitive and may be driven by either AC
(input range
−
24V to +24V RMS, 50 to 1000 Hz) or DC (input range
−
24V to
+24VDC). Each input has a switchable low-pass filter.
Although requiring only two, 8-bit ports, the board occupies four ports.
1.2 ACCESSORIES
The PC104-PDISO8 is a combination digital I/O board with signal conditioning
installed. Most accessory boards are intended to provide signal conditioning or easy
to access signal termination. In general, it does not require additional signal
conditioning.
WARNING
We strongly recommend against using screw terminal boards with the
PC104-PDISO8. The board is intended to sense and control high voltages. A screw
terminal board would expose yourself and others to high voltage signals.
Rather, we recommend that you construct a safe cable to carry your signals directly
from your equipment to the board’s connector.
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