6. PARAMETER SETTING MODE
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IMR01N12-E7
LBA deadband (Lbd1, Lbd2)
The LBA deadband gives a neutral zone to prevent the Control loop break alarm (LBA) from malfunctioning
caused by disturbance.
Data range:
0.0 to Input span
(Varies with the setting of the Decimal point position)
Factory set value:
0.0
LBA Deadband function:
The LBA may malfunction due to external disturbances. To prevent malfunctioning due to
external disturbance, LBA deadband (LBD) sets a neutral zone in which LBA is not
activated. When the Measured value (PV) is within the LBD area, LBA will not be
activated. If the LBD setting is not correct, the LBA will not work correctly.
LBD differential gap *
Alarm area
Alarm area
Non-alarm area
A
B
Set value (SV)
LBD set value
Low
High
If the LBA function detects an error occurring in the control loop, but cannot specify the location, a
check of the control loop in order. The LBA function does not detect a location which causes alarm
status. If LBA alarm is ON, check each device or wiring of the control loop.
LBA function is not operative when:
AT function is activated.
The controller is in STOP mode.
LBA function is set to “OFF.”
LBA function is not assigned to Event (ES3) or Event 4 (ES4).
If the LBA time is too short or does not match the controlled object requirements, LBA may turn ON
or OFF at inappropriate time or remain OFF. Change the LBA time based on the malfunction.
While the LBA is ON (under alarm status), the following conditions cancel the alarm status and LBA
will be OFF:
The Measured value (PV) rises beyond (or falls below) the LBA determination range within
the LBA time
.
The Measured value (PV) enter within the LBA deadband.
A: During temperature rise:
Alarm area
During temperature fall:
Non-alarm area
B: During temperature rise:
Non-alarm area
During temperature fall:
Alarm area
* TC/RTD input: 0.8
C [
F] (fixed)
Pressure sensor input and Voltage/Current input: 0.8 % of input span (fixed)