Allen-Bradley LOGIX 5000 Reference Manual page 346

Chapter 3 Filter
346
Example
The LDL2 instruction can attenuate between two frequencies or can amplify
between two frequencies, depending on how you configure the instruction. Since
the Lead and Lag frequencies can be set to values that are larger or smaller than
each other, this instruction may behave as a Lead-Lag block, or, as a Lag-Lead
block, depending on which frequency is configured first. Note that higher orders
increase the execution time for the filter instruction.
This example is the minimal legal programming of the LDL2 function block and is
only used to show the neutral text and generated code for this instruction.
is for internal purposes only and is not a testable case.
Filter Graph
1st order lead-lag
(wLead < wLag)
2nd order lead-lag
(wLead < wLag)
1st order lead-lag
(wLag < wLead)
2nd order lead-lag
(wLag < wLead)
Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
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