Stop At Min. Speed; Ramps - Grundfos MGE Serie Montage- Und Betriebsanleitung

• Alarm And Max
An alarm is given and the pump increases the speed to maximum.
• Alarm and Userdefined speed
An alarm is given and the pump runs at the speed set by the user.
Detection delay
Setting the detection delay 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 when 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 is indicated.
If the pressure is above 7 bar for more than 8 seconds, reset the limit-exceeded warning.
Y
1
2
4 4
A
5 6
X: Time in seconds
Y: Pressure in bar
Pos. Parameter
1 Measured
2 Limit
3 Hysteresis band
4 Limit exceeded when
5 Detection delay
6 Resetting delay
A Limit-exceeded function active
- Action

6.17 "Stop at min. speed"

This stop function can be utilised in for example constant level applications where a boost of pressure is not needed. It is a different type of
stop function than low flow stop but the purpose is the same. The pump stops if there is no or low consumption.
This function monitors the speed of the pump. When the PI-controller has forced the speed of the pump to minimum according to the feedback
value, the pump stops after a set period of time. It remains stopped until the feedback value starts to drop and the PI-controller starts the pump
again.
• Enable Stop at min. speed
Enables the Stop at min. speed function.
• Delay
The delay time the pump must be running at minimum speed before it stops.
• Restart speed
Speed in percentage when the pump must start again, hysteresis. It must be set higher than the Minimum speed of the pump.

6.18 "Ramps"

The ramps determine how quickly the product can accelerate and decelerate during start and stop or setpoint changes.
You can make the following settings:
• acceleration time, 0.1 to 300 s
• deceleration time, 0.1 to 300 s.
The times apply to the acceleration from 0 rpm to a fixed maximum speed and the deceleration from a fixed maximum speed to 0 rpm,
respectively.
At short deceleration times, the deceleration of the product may depend on load and inertia as there is no possibility of actively braking the
product.
If the power supply is switched off, the deceleration of the product only depends on the load and inertia.
52
3
X
Setting
Discharge pressure
5 bar
2 bar
below limit
5 seconds
8 seconds
-
Warning