Rockwell Automation Publication 1715-UM001J-EN-P - December 2020
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Appendix B 1715-IB16D Digital Input Module Diagnostics
Full Diagnostics Configuration
Selecting Full in the Diagnostics pull-down menu loads a set of threshold
default values into the threshold settings.
This must be selected if an EOL is
used.
Figure 76 - Full Diagnostics Threshold Default Values
For a full-diagnostics setting configuration, use these resistor values.
None Diagnostics Configuration
Selecting None in the Diagnostics pull-down menu loads another set of default
values into the threshold settings.
This is selected when no EOL devices are
used.
Figure 77 - None Diagnostics Threshold Default Values
Based on these settings, if the switch is closed, the input reports an ‘on’
condition anytime the voltage is above ~14.5V, but does not report a short
circuit, because there is no way to get the voltage to rise to 32V.
IMPORTANT
These are the most common commercially available EOL devices.
Table 59 - Full Diagnostics Resistor Values
Item
Value
R1
15 k
(1%) - power 0.5 W (max power dissipated 0.128 W)
R2
3.9 k
(1%) - power 0.5 W (max power dissipated 0.128 W)
Loop supply voltage=
24V DC (±10%)
Indicates An
‘On’
Condition
Below 5.5V
Causes An ‘Off’
Condition