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47LLC OPERATING MANUAL EM-9505-B Rev.4
Figure 3: Deadband (hysteresis)
Display value
Closeup
Alarm setpoint (hi)
Display value
Deadband works
in the direction of
decreasing display
value.
Deadband
Alarm output
With deadband
Without deadband
(setting value: 0000)
Preventing chattering
Figure 4: ON delay time
Display value
Alarm setpoint (hi)
ON delay time
ON delay time
(1)
(2)
Alarm output
Alarm output is not provided
with a sudden change.
(1) The display value once exceeds the alarm setpoint but
becomes below it during ON delay time period.
Therefore alarm output is not provided.
(2) The display value exceeds the setpoint and stays over
the ON delay time period. Therefore alarm output is
provided.
Figure 2: All trip points set to high setting
Figure 1: Typical L/H trip setting
Display value
H alarm setpoint
L alarm setpoint
HH alarm output (hi)
L alarm output (lo)
‘HH’ indicator
‘P’ indicator
‘L’ indicator
HH alarm setpoint
LL alarm setpoint
H alarm output (hi)
LL alarm output (lo)
‘H’ indicator
‘LL’ indicator
Display value
L alarm output (hi)
Low or high trip action can be set for each alarm output.
‘LL’ , ‘L’ , ‘H’ and ‘HH’ indicators are fixed for each setpoint.
Therefore, even in case setting LL alarm output to high trip
action, for example, ‘LL’ indicator turns on at alarm.
H alarm setpoint
L alarm setpoint
HH alarm setpoint
LL alarm setpoint
HH alarm output (hi)
H alarm output (hi)
LL alarm output (hi)
‘HH’ indicator
‘P’ indicator
‘L’ indicator
‘H’ indicator
‘LL’ indicator