Endress+Hauser Liquistation CSF34 - Page 129

Liquistation CSF34 Operation
Endress+Hauser 129
Menu/Setup/Additional functions/Limit switches/Limit switch 1 ... 8
Function Options Info
Range lower value Settings depend on the
measured value
Operating mode = Out of range check or In
range check
Range upper value
1
2
t
MV
t
1
t
2
t
3
t
4
A B
3
3
1
2
t
MV
t
1
t
2
t
3
t
4
3
A0028524
 68 Range monitoring outside (A) and within (B) a range (without hysteresis and switch-on delay)
1 End of range
2 Start of range
3 Alarm range
t
1-4
An event is generated
• If measured values (MV) are increasing, the relay contact is closed when the switch-on point is exceeded
(Range lower value + Hysteresis) and the start delay (Start delay) has elapsed.
• If measured values are decreasing, the relay contact is reset when the switch-off point is undershot (Range
upper value - Hysteresis) and after the drop-out delay (Switch off delay).
Hysteresis Settings depend on the
measured value
Operating mode ≠ Change rate
1
3
t
MV
t
1
t
2
2
A0028525
 69 Hysteresis taking the example of limit value
overshoot
1 Limit value
2 Alarm range
3 Hysteresis range
t
1,2
An event is generated
The hysteresis is needed to ensure a stable
switching behavior.
The device software adds or subtracts the value
set here to/from the limit value (Limit value,
Range lower value or Range upper value). This
results in double the Hysteresis value for the
hysteresis range around the limit value. An
event is then only generated if the measured
value (MV) completely passes through the
hysteresis range.
Start delay
Operating mode ≠ Change
rate
0 to 9999 s
Factory setting
0 s
Synonyms: pick-up and drop-out delay
Switch off delay
Operating mode ≠ Change
rate