ABB ACQ810-04, Hardware Manual, Page: 58 / 144

58 Planning the electrical installation
Implementing the Power loss ride-through function
Implement the power loss ride-through function as follows:
1. Activate the power loss ride-through function of the drive (parameter
47.02 Undervolt ctrl in the Standard Pump Control Program).
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.
WARNING! Make sure that the 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 power factor compensation capacitors with the
drive
Power factor compensation is not needed with AC drives. However, if a drive is to be
connected in a system with compensation capacitors installed, note the following
restrictions.
WARNING! Do not connect power factor compensation capacitors or harmonic
filters to the motor cables (between the drive and the motor). They are not
meant to be used with AC drives and can cause permanent damage to the drive
or themselves.
If there are power factor compensation capacitors in parallel with the three phase input of
the drive:
1. Do not connect a high-power capacitor to the power line while the drive is connected.
The connection will cause voltage transients that may trip or even damage the drive.
2. If capacitor load is increased/decreased step by step when the AC drive is connected
to the power line, ensure that the connection steps are low enough not to cause
voltage transients that would trip the drive.
Check that the power factor compensation unit is suitable for use in systems with AC
drives, ie, harmonic generating loads. In such systems, the compensation unit should
typically be equipped with a blocking reactor or harmonic filter.
Implementing a safety switch between the drive and the
motor
It is recommended to install a safety switch between the permanent magnet synchronous
motor and the drive output. The switch is needed to isolate the motor during any
maintenance work on the drive.