ABB ACS880-01 Series, Hardware Manual

Page: 77 / 224

Planning the electrical installation 77
Switching the motor power supply from drive to direct-on-line
1. Stop the drive and the motor with the drive control panel (drive in local control
mode) or with the external stop signal (drive in remote control mode).
2. Open the main contactor of the drive with S11.
3. Switch the motor power supply from the drive to direct-on-line with S40.
4. Wait for 10 seconds to allow the motor magnetization to die away.
5. Start the motor with S41.
Switching the motor power supply from direct-on-line to drive
1. Stop the motor with S42.
2. Switch the motor power supply from direct-on-line to the drive with S40.
3. Close the main contactor of the drive with switch S11 (-> turn to position ST for
two seconds and leave at position 1).
4. Start the drive and the motor with the drive control panel (drive in local control
mode) or with the external start signal (drive in remote control mode).
Protecting the contacts of relay outputs
Inductive loads (relays, contactors, motors) cause voltage transients when switched
off.
The relay contacts on the drive control unit are protected with varistors (250 V)
against overvoltage peaks. In spite of this, it is highly recommended that inductive
loads are equipped with noise attenuating circuits (varistors, RC filters [AC] or diodes
[DC]) in order to minimize the EMC emission at switch-off. If not suppressed, the
disturbances may connect capacitively or inductively to other conductors in the
control cable and form a risk of malfunction in other parts of the system.
Install the protective component as close to the inductive load as possible. Do not
install protective components at the relay outputs.
ACS880-01 HW.book Page 77 Monday, July 1, 2013 4:51 PM