ELECTRICAL WIRING-3 PHASE P12
Besides current and power rating of the VFD is the key parameter to
drive the motor, the EMC filter between VFD and motor is the most
critical device to prevent the motor bearing, shaft and insulation
system from being damage by VFD inverter high frequency bearing
current noise. It is necessar y to consult your VFD supplier to
optimize the EMC filter. Some of the VFD supplier has EMC filter build in. If not it is
necessar y to consult VFD supplier to add EMC filter module between VFD and Motor.
For heavy power version, it should need a large current EMC filter which typical name
du/dt filters.
6. 4 SOFT STARTER
Another low voltage starter is soft starter, it can be 1 phase, 2 phase or 3 phase power input and connect direct
to the motor terminals. It can setup initiate voltage and ramp up to full power smoothly to prevent current
surge; and stop the pump slowly. Soft stop (which helps eliminate water hammer)
The Key Benefits Of Soft Start
1. Smooth acceleration without the torque transients associated with electro-
mechanical reduced voltage starters.
2. Voltage or current is applied gradually, without the voltage and current
transients associated with electro-mechanical reduced voltage starters.
3. Lower start currents and/or shorter start times because constant current
control gives higher torque as motor speed increases.
4. Easy adjustment of start performance to suit the specific motor and load.
5. Precise control over the current limit.
6. Consistent performance even with frequent starts.
7. Reliable performance even if load characteristics var y between starts (eg
loaded or unloaded starts).
It is necessar y to refer to the soft starter manufacturer for detail starting conduction setting.
Table of Motor current rating for reference if there is no current rating on the motor plate.
KW
7.5
11
15
18
.
5
22
25
30
37
45
HP
10
15
20
25
30
35
40
50
60
27
39
52
64
75
85
103
126
150
16
22
30
37
44
52
60
72
85
14
20
27
33
39
45
52
64
76
13
18
25
30
35
38
48
59
73
12
18
23
29
33
39
45
55
65
9
14
17
21
25
30
35
42
49
220-230 V
440 V
380-400 V
460 V
500 V
660-690 V
Motor Power
Current rating at different voltages
L1,L2,L3
Mains Power
T1,T2,T3
Output to Motor
U1,V1 W1 Delta
Connection
