Allen-Bradley LOGIX 5000 Reference Manual page 63

Process Control Instructions
LEAD_LAG Structure
Input Parameter Data Type
EnableIn BOOL
In REAL
Initialize BOOL
Lead REAL
Lag REAL
Gain REAL
Bias REAL
TimingMode DINT
OversampleDT REAL
RTSTime DINT
RTSTimeStamp DINT
Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
Description
Enable input. If cleared, the instruction does not execute and
outputs are not updated.
Default is set.
The analog signal input to the instruction.
Valid = any float
Default = 0.0
Request to initialize filter control algorithm. When Initialize is
set, Out = (In x Gain) + Bias.
Default = cleared
The lead time in seconds. Set Lead = 0.0 to disable the lead
control algorithm. If Lead < 0.0, the instruction sets the
appropriate bit in Status and limits Lead to 0.0. If Lead >
maximum positive float, the instruction sets the appropriate
bit in Status.
Valid = any float 0.0
Default = 0.0
The lag time in seconds. The minimum lag time is DeltaT/2. If
Lag < DeltaT/2, the instruction sets the appropriate bit in
Status and limits Lag to DeltaT/2. If Lag > maximum positive
float, the instruction sets the appropriate bit in Status.
Valid = any float DeltaT/2
Default = 0.0
The process gain multiplier. This value allows the simulation of
a process gain. The In signal is multiplied by this value. I = (In
x Gain) + Bias
Valid = any float
Default = 1.0
The process offset level. This value allows the simulation of an
ambient condition. This value is summed with the results of
the multiplication of In times Gain. I = (In x Gain) + Bias
Valid = any float
Default = 0.0
Selects timing execution mode.
0 = Periodic rate
1 = Oversample mode
2 = Real-time sampling mode
Valid = 0 to 2
Default = 0
For more information about timing modes, see Function Block
Attributes.
Execution time for oversample mode.
Valid = 0 to 4194.303 seconds
Default = 0
Module update period for real time sampling mode
Valid = 1 to 32,767ms
Default = 1
Module time stamp value for real time sampling mode.
Valid = 0 to 32,767ms
Default = 0
Chapter 1
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