English (GB)
41
10.15 ""Limit-exceeded function""
This function can monitor a measured parameter or
one of the internal values such as speed, motor load
or motor current. If a set limit is reached, a selected
action can take place. You can set two
limit-exceeded functions meaning that you can
monitor two parameters or two limits of the same
parameter simultaneously.
The function requires setting of the following:
"Measured"
Here you set the measured parameter which is to be
monitored.
"Limit"
Here you set the limit which activates the function.
"Hysteresis band"
Here you set the hysteresis band.
"Limit exceeded when"
Here you can set if you want the function to be
activated when the selected parameter exceeds or
drops below the set limit.
•
""Above limit""
The function is activated if the measured
parameter exceeds the set limit.
•
""Below limit""
The function is activated if the measured
parameter drops below the set limit.
"Action"
If the value exceeds a limit, you can set an action.
You can select the following actions:
•
""No action""
The pump remains in its current state. Use this
setting if you only want to have a relay output
when the limit is reached. See section
10.9 "Signal relay" (""Relay outputs"")
.
•
""Warning/alarm""
A warning is given.
•
""Stop""
The pump stops.
•
""Min.""
The pump reduces speed to minimum.
•
""Max.""
The pump increases speed to maximum.
Detection delay
You can set a detection delay which ensures that the
monitored parameter stays above or below a set limit
in a set time before the function is activated.
Resetting delay
The resetting delay is the time from which the
measured parameter differs from the set limit
including the set hysteresis band and until the
function is reset.
Example
The function is to monitor the outlet pressure from a
CRE pump. If the pressure is below 5 bar for more
than 5 seconds, a warning must be given. If the
outlet pressure is above 7 bar for more than 8
seconds, reset the limit exceeded warning.
Fig. 44
Limit exceeded (example)
T
M
06
46
03
25
15
Pos.
Setting parameter
Setting
1
"Measured"
Outlet pressure
2
"Limit"
5 bar
3
"Hysteresis band"
2 bar
4
"Limit exceeded when"
Below limit
5
"Detection delay"
5 seconds
6
"Resetting delay"
8 seconds
A
"Limit exceeded function
active"
-
-
"Action"
Warning
1
2
4
4
5
6
3
A
Time [s]
