ABB ACS800-02, Hardware Manual

Page: 27 / 128

Planning the electrical installation
27
Planning the electrical installation
What this chapter contains
This chapter contains the instructions that you must follow when selecting the motor,
the cables, the protections, the cable routing and the way of operation for the drive
system. Always follow local regulations.
Note: If the recommendations given by ABB are not followed, the drive may
experience problems that the warranty does not cover.
To which products this chapter applies
This chapter applies to the ACS800-01/U1, the ACS800-02/U2 , the ACS800-04/U4
and ACS800-07/U7 types up to -0610-x.
Checking the compatibility of the motor
See Technical data for the drive ratings and the motor connection data.
WARNING! Operation is not allowed if the motor nominal voltage is less than 1/2 of
the drive nominal input voltage. The allowed range of the motor nominal current is
1/6 ... 2 ·
I
2hd
of the drive in DTC control and 0 ... 2 · I
2hd
in scalar control. The
control mode is selected by a drive parameter.
Protecting the motor winding and bearings
The output of the drive comprises – regardless of output frequency – pulses of
approximately 1.35 times the mains network voltage with a very short rise time. This
is the case with all drives employing modern IGBT inverter technology.
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 on the motor
insulation.
Modern variable speed drives with their fast rising voltage pulses and high switching
frequencies can cause current pulses through the motor bearings which can
gradually erode the bearing races.
The stress on motor insulation can be avoided by using optional ABB du/dt filters.
du/dt filters also reduce bearing currents.