Ac Power Supply Considerations; It Networks - WEG CFW-11 Series User Manual

ATTENTION!
A contactor or another device that frequently disconnects and reapplies the AC supply to the inverter,
in order to start and stop the motor, may cause damage to the inverter power section. The drive
is designed to use control signals for starting and stopping the motor. If used for that purpose, the
input device must not exceed one operation per minute; otherwise, the inverter may be damaged.
ATTENTION!
The power supply that feeds the inverter shall have a grounded neutral. In case of IT networks, follow
the instructions described in
NOTE!
The input power supply voltage shall be compatible with the inverter rated voltage.
NOTE!
Power factor correction capacitors are not needed at the inverter input (R, S, T) and shall not be
installed at the output of the inverter (U, V, W).

3.2.3.1.1 AC Power Supply Considerations

Suitable for use in circuits capable of delivering not more than 65,000 Arms symmetrical at 240 V or 480 V for
maximum 480 V rated models, and 14,000 Arms symmetrical at 600 V for maximum 690 V rated models, when
protected by inverse-time circuit breakers rated for the input voltage of the drive and 130 % of the full-load motor
output current rating.
Table 3.9 - Maximum rated current of the circuit breakers according to the inverter model
Frame Size
B
C
D
E
F
G
H

3.2.3.1.2 IT Networks

ATTENTION!
For using the inverter CFW11...T5 or T6 in IT networks (neutral conductor not grounded or grounded
via high ohmic value resistor) or in corner-grounded delta networks, the following modifications are
required in the connections of some internal components to ground:
Frame sizes B, C and D: remove the screw as indicated in
Frame size E: change the position of the J1 jumper on the PRT board from
(XIT), according to
Frame sizes F , G and H: disconnect the cable with the ring tongue lug from the ground busbar and
connect it to the isolated point on the power terminal block as shown in the
Figure 3.29 on page 3-37
That is necessary to avoid damage to the inverter when operating with a line input shorted to ground.
Item 3.2.3.1.2 IT Networks on page
Maximum Circuit Breaker
Current Rating
30 A
125 A
250 A
250 A
800 A
800 A
1200 A
Figure 3.27 on page 3-36.
and Figure 3.30 on page 3-37
Installation and Connection
3-35.
Enclosure Dimensions
(D x H x W) mm
203 x 457 x 508
203 x 610 x 508
203 x 762 x 610
254 x 914 x 660
600 x 2000 x 800
600 x 2000 x 1400
600 x 2000 x 1400
Figure 3.26 on page 3-36.
(XE1) to "NC"
Figure 3.28 on page
.
CFW-11 | 3-35
3
3-37,