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5.3.2.1 Digital Inputs (Mixed Mode)
The following table lists the available digital input configuration options available when in mixed mode.
Some options available in digital-only mode are not available in mixed mode. Descriptions and example
diagrams are provided starting in section
Selection
Measurement
Description
DIN
Digital Input
2-bit binary digital input
RATE
Frequency
Measures the frequency of rising edges
WIDTH
Pulse Width
Measures the active time of a signal
DUTY
Duty Cycle
Measures the % of active time of a signal
COUNT
Up Counter / Totalizer Counter with Enable and Reset
Important:
Digital input signals (pulse inputs)
must
be referenced to ground when
Mixed Mode
is used.
Negative offsets at pulse inputs may cause interference and noisy/incorrect readings in
analog (mA/V) process input signals.
The table below shows the binary-weighted values for the 2-bit Digital Input (DIN) function in mixed
mode.
Input 1
Input 0
Reading
Inactive
Inactive
0
Inactive
Active
1
Active
Inactive
2
Active
Active
3
5.3.2.2 Process Inputs (Mixed Mode)
The following process input configuration options are available in mixed input mode: 4-20 mA current loop,
0-1.0 V voltage input, 0-2.0 V voltage input. Current loop readings are rounded to the nearest 0.1 mA and
voltage readings are rounded to the nearest 10 mV.
5.3.2.2.1 4-20 mA Device Connection
The Current Loop interface measures the current into the selected input by converting it to a
voltage measurement across a fixed 49.9-ohm resistor.
Figure 18: 4-20 mA device connection diagram
