NIVELCO UNICONT PMG-500, User And Programming Manual, Page: 29 / 41

pmg511en21p01 29
When performing auto-tuning, the LBA detection band [LBaB] and LBA monitoring time [LBaT] are automatically
set based on the auto-tuning value.
For AT (auto-tuning) / manual control / stop control, the loop break alarm [LBA] does not work.
5.7.8 LBA Monitoring Period [PAR4 → LBaT]
The LBA monitoring time can be set to control the temperature changes of the controlled section. Automatic
adjustment with automatic tuning. Default setting: 0 s.
– Regardless of the operation of the alarm [AL- □] (including when the LBA supervision time is 0) , the
integration time × 2 value is automatically saved after running auto-tuning.
– (If the SV is outside the auto-adjustment range, the auto-adjustment will be set to the maximum or
minimum.)
– Except for changing the input type, restarting auto tuning, and setting the LBA monitoring time manually,
it maintains the current SV.
– Automatic setting range: 0020… 9999
5.7.9 LBA Detection Band [PAR4 → LBaB]
The minimum deviation value can be set to decrease during the LBA monitoring time. Automatic adjustment with
automatic tuning. (If the SV is outside the auto adjustment range, the auto adjustment will be set to the maximum
or minimum value.)
– Except changing the input type, restarting auto tuning, setting the LBA monitoring time manually, it
maintains the current SV.
– Regardless of the operation of the alarm (including the LBA monitoring time as “0”) , the integration time
× 2 value is automatically saved after running auto tuning.
Parameter Description Automatic setting range Default
LBaB
Temperature H (upper) 002.0…100.0 ° C / ° F 002 ° C / ° F
Temperature L (lower) 0002…010.0 ° C / ° F 002.0 ° C / ° F
Analog 000.2…010.0% F.S. 000.2% F.S.
Example: Checks the control loop and issues an alarm when the temperature of the object changes. For heating control
(cooling control) , if the MV control output is 100% (0% for cooling control) and the PV does not rise beyond the LBA
detection band [LBaB] during the LBA monitoring time [LBaT] , or if the control output is MV 0% (For 100% cooling
control) and the PV does not fall below the LBA detection band [LBaB] during the LBA monitoring time [LBaT] , the alarm
output is ON.
SV
PV
Temperature
Control
output MV
100%
0%
Loop break
alarm(LBA)
Time
LBA monitoring
time
LBA invalid LBA invalid
LBA invalid
LBA monitoring
time
LBA monitoring
time
LBA monitoring
time
LBA monitoring
time
        
LBA detection
band
LBA detection
band
LBA detection
band
LBA detection
band