OPERATION
Adaptive Control for Stopping
In an adaptive control soft stop, the EMX3 controls the current in order to stop the motor within a specified time and using a selected
deceleration profile. Adaptive Control can be useful in extending the stopping time of low inertia loads.
Every application has a particular stopping profile, based on characteristics of the load and the motor. Adaptive Control offers three
different stopping profiles. Choose the adaptive control profile that best matches your application requirements.
NOTE
Adaptive control does not actively slow the motor down and will not stop the motor faster than a coast to stop. To
shorten the stopping time of high inertia loads, use brake.
CAUTION
Adaptive Control controls the motor's speed profile, within the programmed time limit. This may result in a higher level
of current than traditional control methods.
•
Adaptive Control
To use Adaptive Control to control stopping performance:
1.
Select Adaptive Control from the Stop Mode menu (parameter 2H)
2.
Set the desired Stop Time (parameter 2I)
3.
Select the required Adaptive Stop Profile (parameter 2J)
Sp
ee
d
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0
04
83
5.
C
1
2
3
4
Adaptive Stop Profile
(parameter 2J):
1. Early Deceleration
2. Constant Deceleration
3. Late Deceleration
4.
Stop Time
(parameter 2I)
Time
The first Adaptive Control stop will be a normal soft stop. This allows the EMX3 to learn the characteristics of the connected motor.
This motor data is used by the EMX3 during subsequent Adaptive Control stops.
NOTE
Adaptive Control will control the load according to the programmed profile. Stopping current will vary according to the
selected deceleration profile and stop time.
If replacing a motor connected to an EMX3 programmed for Adaptive Control starting or stopping, or if the starter has
been tested on a different motor prior to actual installation, the starter will need to learn the characteristics of the new
motor. The EMX3 will automatically re-learn the motor's characteristics if parameter 1A
Motor Full Load Current
or
parameter 2K
Adaptive Control Gain
is changed.
•
Pump stopping
The hydraulic characteristics of pump systems vary considerably. This variation means the ideal deceleration profile and stop time
will vary from application to application. The table provides guidelines on selecting between Adaptive Control deceleration profiles,
but we recommend testing the three profiles to identify the best profile for the application.
Adaptive Stop Profile
Application
Late Deceleration
High head systems where even a small decrease in motor/pump speed results in a rapid
transition between forward flow and reverse flow.
Constant Deceleration
Low to medium head, high flow applications where the fluid has high momentum.
Early Deceleration
Open pump systems where fluid must drain back through the pump without driving the pump
in reverse.
User Manual (710-04840-00M) |
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