Using A Safety Switch Between The Drive And The Motor; Implementing A Bypass Connection - ABB ACS580 Series Hardware Manual

122 Guidelines for planning the electrical installation
after the break automatically, or remain closed over the break. Depending on the
contactor control circuit design, this can require an additional hold circuit,
uninterruptible auxiliary power supply or auxiliary power supply buffering.
Note: If the power loss lasts so long that the drive trips on undervoltage, a fault
reset and a fresh start command is required to continue operation.
Implement the power-loss ride-through function as follows:
1. Enable the power-loss ride-through function of the drive (parameter 30.31).
2. If the installation is equipped with a main contactor, prevent its tripping at
the input power break. For example, use a time delay relay (hold) in the
contactor control circuit.
3. Enable the automatic restart of the motor after a short power supply break:
• Set the start mode to automatic (parameter 21.01 or 21.19, depending on
the motor control mode being used).
• Define the automatic restart time (parameter 21.18).
WARNING!
Make sure that a flying restart of the motor will not cause any danger. If you
are in doubt, do not implement the power loss ride-through function.

Using a safety switch between the drive and the motor

ABB recommends to install a safety switch between the permanent magnet motor
and the drive output. The switch is needed to isolate the motor from the drive
during maintenance work on the drive.

Implementing a bypass connection

If bypassing is required, employ mechanically or electrically interlocked contactors
between the motor and the drive and between the motor and the power line. Make
sure with interlocking that the contactors cannot be closed simultaneously. The
installation must be clearly marked as defined in IEC/EN/UL 61800-5-1, subclause
6.5.3, for example, "THIS MACHINE STARTS AUTOMATICALLY".
WARNING!
Never connect the drive output to the electrical power network. The
connection may damage the drive.