ABB ACQ810-04, Hardware Manual, Page: 61 / 144

Planning the electrical installation 61
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 the local control
mode) or the external stop signal (drive in the 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 to position 1).
4. Start the drive and the motor with the drive control panel (drive in the local control
mode) or the external start signal (drive in the 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 JCU control unit are protected with varistors (250 V) against
overvoltage peaks. In spite of this, it is highly recommended to equip inductive loads 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.
24 V DC
230 V AC
230 V AC
1
2
3
4
1) Relay outputs; 2) Varistor; 3) RC filter; 4) Diode