ABB ACS 600 MultiDrive, Safety And Product Information

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Safety Instructions
8 ACS 600 MultiDrive
The function is achieved by disconnecting the control voltage to the
power semiconductors of the inverter. Thus it is not possible for the
power semiconductors to switch and generate the AC voltage needed
to rotate the motor. In case of faulty main circuit components, the DC
voltage from the busbar can be connected to the motor but an AC
motor cannot rotate without the field generated by the AC voltage.
The operator activates the Prevention of Unexpected Start with a
switch mounted on the control desk. When Prevention of Unexpected
Start is activated, the switch is turned to position “
0 ”. A signal lamp will
be lit on the control desk, indicating that Prevention of Unexpected
Start is activated.
WARNING! Prevention of Unexpected Start does not disconnect
the voltage of the main and auxiliary circuits. Therefore
maintenance work on electrical parts can only be carried out after
disconnecting the drive system.
Motor Connections
WARNING! Operation is not allowed if the motor nominal voltage is
less than one half of the ACx 600 nominal input voltage, or the motor
nominal current is less than 1/6 of the ACx 600 nominal output current
(
I
2base
for 50s/60s duty cycle).
Pulses in the Drive
Output
As with all frequency converters employing the most modern IGBT
inverter technology, the ACS 600 output comprises – regardless of
output frequency – pulses of approximately 1.35 times the mains
network voltage with a very short rise time.
The voltage of the pulses can be almost double at the motor terminals,
depending on the motor cable properties. This in turn can cause
additional stress to the motor insulation.
Modern variable speed drives with their fast rising voltage pulses and
high switching frequencies can cause current pulses through the
bearings whose repeated discharging can gradually erode the bearing
races.
Protecting the Motor
Wiring
The stress to motor inslulation can be avoided by optional ABB du/dt
filters. du/dt filters also reduce bearing currents.