Rockwell Automation Publication 1734-UM013C-EN-P - August 2010
89
Configure the Module in a GuardLogix Controller
Chapter
6
Configure the
Input Configuration Tab
Follow this procedure to complete the input configuration. Refer to
Chapter
for related information.
1.
From the Module Properties dialog box, click the Input Configuration tab.
2.
Assign the Point Operation Type.
When you choose Equivalent or Complementary, you must also assign an
appropriate Discrepancy Time.
A discrepancy time setting of 0 ms means that the channels in a dual
configuration can be discrepant for an infinite amount of time without a
fault being declared.
For a discrepancy time setting of 0 ms, the evaluated status of the inputs
still go to the Safety State due to a ‘cycle inputs’ required condition, but
due to the 0 ms discrepancy time setting, a fault will not be declared.
2
3
4
5
6
7
Choose
Description
Single
Inputs are treated as single channels. Note that in many
cases, dual-channel safety inputs are configured as two
individual single channels. This does not affect pulse
testing because it is handled on an individual channel
basis.
Equivalent
(1)
Inputs are treated as a dual-channel pair. The channels
must match within the discrepancy time or an error is
generated.
Complementary
(1)
Input are treated as a dual-channel pair. They must be in
opposite states within the discrepancy time or an error is
generated.
(1) Be aware that configuring discrepancy time on safety I/O modules masks input discrepancies
detected by the controller safety instructions. Status can be read by the controller to obtain this fault
information.