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Function: Limiting output (1 or 2 point)
The limit switch function can be used for remote control or alarm systems.
1 Point
Time
LI1
mid
active
inactive
½ Hyst
Signal
Hysteresis
½ Hyst
ON
OFF
2 Point
ON
OFF
Time
Signal
LI2
max
active
inactive
½ Hyst
Hysteresis
½ Hyst
LI1
min
inactive
active
½ Hyst
Hysteresis
½ Hyst
NO
NC
active
inactive
Work State
The function Limit allows you to set an alert whenever
predefined values (e.g. flow rate) are exceeded.
Limit defines upper (L2i
max
) and lower (Li1
min
) values of
thresholds which, when exceeded, activate a switch (alert).
In order to prevent oscillating between active and inactive
states when the values fluctuate around a threshold, a hys-
teresis bands (see adjacent diagram) can be defined in
which the switch will remain active once it has been trig-
gered to this state.
When the value passes below or above these bands, the
switch will be deactivated. The hysteresis bands are calcu-
lated as a percentage of the threshold values (Li).
Signal behavior:
1 Point (Balanced)
Setpoints (Li1) and resetpoints (½ Hyst) are the setpoint
values expanded up and down by half the hysteresis value.
2 Point (Unbalanced)
Setpoints (Li1/Li2) and resetpoints (½ Hyst) are the setpoint
values expanded upwards or downwards by half the hyste-
resis value.
Parameters that can be set:
Lower value
[Li1
min
]
:
≥0
(factory setting: Qmin)
Upper value
[Li2
max
]
:
≤Q
max
(factory setting: Qmax)
Hysteresis
[HYST]
:
0...99.9 %
(factory setting: 5 %)
The switches that are activated by the above parameters can be set to NO (Normally Open) or to
NC (Normally Closed). This choice is dependent on your needs.
Limit switch [NO]
:
Contact open, closes when triggered (active).
Limit switch [NC]
:
Contact closed, opens when triggered (active).
