E5CNH E5AN-H E5EN-H Digital Controllers User's Manual - OMRON

Loop Burnout Alarm Section 4-12
Operation Level 9. Press the O Key for at least one second to move from the initial setting
C
PV/SP
level to the operation level.
4-12 Loop Burnout Alarm
4-12-1 Loop Burnout Alarm (LBA)
114
25.0
100.0
Set point
LBA detection
time
(1)
LBA OFF
The loop burnout alarm can be used only with standard models.
With a loop burnout alarm, there is assumed to be an error in the control
loop if the control deviation (SP − PV) is greater than the threshold set in
the LBA Level parameter and if the control deviation is not reduced by at
least the value set in the LBA Detection Band parameter within the LBA
detection time.
Loop burnout alarms are detected at the following times.
Area where LBA
is not detected
LBA detection
time
LBA band LBA band
LBA band
LBA detection
time
(2) (3) (4) (5) (6) (7)
LBA ON LBA OFF
LBA detection
time
LBA ON
LBA level
LBA level
If the control deviation is reduced in the area between 1 and 2 (i.e., the set
point is approached) and the amount the control deviation is reduced is at
least equal to the LBA band, the loop burnout alarm will remain OFF.
The process value is within the LBA level between 3 and 4, and thus loop
burnout alarms will not be detected. (The loop burnout alarm will remain OFF.)
If the process value is outside the LBA level between 4 and 5 and the control
deviation is not reduced by at least the LBA band within the LBA detection
time, the loop burnout alarm will turn ON.
If the control deviation is reduced in the area between 5 and 6 (i.e., the set
point is approached) and the amount the control deviation is reduced is at
least equal to the LBA band, the loop burnout alarm will turn OFF.
If the control deviation is reduced in the area between 6 and 7 (i.e., the set
point is approached) and the amount the control deviation is reduced is less
than the LBA band, the loop burnout alarm will turn ON.
If the LBA detection time, LBA level, LBA detection band, and PID settings
are not appropriate, alarms may be detected inappropriately or
alarms may not be output when necessary.
Loop burnout alarms may be detected if unexpectedly large disturbances
occur continuously and a large deviation does not decrease.