OPERATION
Kickstart
Kickstart provides a short boost of extra torque at the beginning of a start, and can be used in conjunction with current ramp or
constant current starting.
Kickstart can be useful to help start loads that require high breakaway torque but then accelerate easily (for example helical rotor
pumps).
Cu
rr
ent
(%
m
ot
or
ful
l l
oa
d c
ur
re
nt
)
1
2
6
4
5
3
1:
Kickstart Level
(parameter 2G)
2:
Kickstart Time
(parameter 2F)
3:
Initial Current
(parameter 2C)
4:
Start Ramp Time
(parameter 2B)
5:
Current Limit
(parameter 2D)
6: Full voltage current
Rotor speed (% full speed)
Adaptive Control for Starting
In an adaptive control soft start, the EMX3 adjusts the current in order to start the motor within a specified time and using a selected
acceleration profile.
CAUTION
Adaptive Control cannot start the motor faster than a direct on-line (DOL) start. If the start ramp time (parameter 2B) is
shorter than the motor's DOL start time, starting current may reach DOL levels.
Every application has a particular starting profile, based on characteristics of the load and the motor. Adaptive Control offers three
different starting profiles, to suit the requirements of different applications. Selecting a profile that matches the inherent profile of
the application can help smooth out acceleration across the full start time. Selecting a dramatically different Adaptive Control
profile can somewhat neutralise the inherent profile.
The EMX3 monitors the motor's performance during each start, to improve control for future soft starts.
•
Adaptive Control
To use Adaptive Control to control starting performance:
1.
Select Adaptive Control from the Start Mode menu (parameter 2A)
2.
Set the desired Start Ramp Time (parameter 2B)
3.
Select the desired Adaptive Start Profile (parameter 2E)
4.
Set a start Current Limit (parameter 2D) sufficiently high to allow a successful start. The first Adaptive Control start will be a
Constant Current start. This allows the EMX3 to learn the characteristics of the connected motor. This motor data is used by
the EMX3 during subsequent Adaptive Control starts.
Sp
ee
d
0
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
04
82
7.
C
1
2
3
4
Adaptive Start Profile
(parameter 2E):
1. Early Acceleration
2. Constant Acceleration
3. Late Acceleration
4.
Start Ramp Time
(parameter 2B)
Time
NOTE
Adaptive Control will control the load according to the programmed profile. Start current will vary according to the
selected acceleration profile and the programmed start time.
If replacing a motor connected to an EMX3 programmed for Adaptive Control starting or stopping, or if the starter has
User Manual (710-04840-00M) |
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