62 Guidelines for planning the electrical installationImplementing the Emergency stop functionFor safety reasons, install the emergency stop devices at each operator control stationand at other operating stations where emergency stop may be needed. You can implementthe emergency stop function using the Safe torque off function of the drive module (seechapter Safe torque off function on page 135). Design the emergency stop according torelevant standards.Note: Pressing the stop key on the control panel of the drive does not generate anemergency stop of the motor or separate the drive from dangerous potential.Implementing the Safe torque off functionSee chapter Safe torque off function on page 135.Implementing the Power loss ride-through functionImplement the power-loss ride-through function as follows:• Check that the power-loss ride-through function of the drive is enabled with parameter30.31 Undervoltage control.• Set parameter 21.01 Vector start mode to Automatic (in vector mode) or parameter21.19 Scalar start mode to Automatic (in scalar mode) to make flying start (startinginto a rotating motor) possible. 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.WARNING! Make sure that the flying restart of the motor will not cause anydanger. If you are in doubt, do not implement the Power-loss ride-throughfunction.Using power factor compensation capacitors with thedrivePower factor compensation is not needed with AC drives. However, if a drive is to beconnected in a system with compensation capacitors installed, contact ABB forinstructions.Implementing a safety switch between the drive and themotorWe recommended that you install a safety switch between the permanent magnet motorand the drive output. The switch is needed to isolate the motor during any maintenancework on the drive.
