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10-6 Comparator Hysteresis Function
A hysteresis width and time is provided for the output relay on/off timing to prevent the output
terminals from chattering.
When the measured value exceeds the set value, the relay is turned on. If the measured value falls
below the set value and it is further reduced by the hysteresis width, or if the hysteresis time has
elapsed, the relay is turned off.
The hysteresis mode, time and width can be set in function modes
f-19
,
f-20
and
f-21
.
10-6-1 Upward 2-level judgment (
f-19 0
)
Relation between OK and HI
When the measured value exceeds the set upper limit value, HI is output. Even if the measured
value falls below the upper limit value after that, OK is not output immediately. OK will be output
when the measured value is reduced by the hysteresis width, or when the hysteresis time has
elapsed.
Relation between OK and LO
Even if the measured value falls below the set lower limit value, LO is not output immediately. LO
will be output when the measured value is reduced by the hysteresis width, or when the
hysteresis time has elapsed.
When the measured value returns above the lower limit value, OK is output immediately.
Judgment example
Hysteresis width
Hi
lo
COMP ON
HI output
OK output
LO output
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Hysteresis time
