ABB XSeries G4 6200 User Manual page 162

Digital or Pulse Inputs
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The digital inputs and pulse inputs must be defined in PCCU32.
Page 32
NAMUR: When in a low impedance, the state must draw more than 2.2 mA;
when in high impedance, the state must draw less than 1.0 mA. It should be
noted that in the NAMUR specification, a low impedance of less than 400
OHMS is considered a short (fault), and a high impedance of greater than
20K OHMS is an open (fault). These two conditions are not monitored.
Open Collector (O.C.): The output transistor or FET must be capable of
sinking 8.2 mA. Total impedance of the circuit must be less than 1K OHM.
Dry Contact (i.e., reed-switch): The device must be capable of sinking 8.2
mA. The total impedance, when active, must be less than 1K OHM. Note:
The pulse inputs on the 2102458-001 are designed to accept relatively high-
speed( approximately 20Khz) signals. Therefore, if a reed-switch or other
mechanical device subject to bouncing contacts is used, the application will
require the use of a capacitor across the contact of the switching device ( a
value of 0.1 uF should be a good starting place).
Active Signal: Must be capable of being connected to a 1K load which is
tied to a 8.2V voltage source. When the output is driven high (above 8.8V),
the load will appear at 215 OHMS connected to a 8.8V. Note: The active
signal type input requires the use of an onboard DAC converter to adjust the
trip threshold of the comparator input. Example: A 0-5V signal will not cause
the input to transition through the NAMUR thresholds. The DAC will be set
to 1.35V (to a value of 69 decimal or 0x45). This will make the apparent
threshold, as seen at the input, to 2.5V.
2104349 rev. AD