ABB ACH580-04, Hardware Manual

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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, make sure that the connection steps are low enough not to cause
voltage transients that would trip the drive.
3. Make sure 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.
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 an ATEX-certified motor thermal protection
With Q971, the drive provides ATEX-certified safe motor disconnection without
contactor using the drive Safe torque off function. To implement the thermal protection of
a motor in explosive atmosphere (Ex motor), you must also:
• use an ATEX-certified Ex motor
• order an ATEX-certified thermistor protection module for the drive (L357), or
acquire and install an ATEX-compliant protection relay
• do the necessary connections.
For more information, see:
Manual code
(English) User's manual
3AXD50000030058 CPTC-02 ATEX-certified thermistor protection module, Ex II (2) GD (L537+Q971)
user's manual
Controlling a contactor between drive and motor
The control of the output contactor depends on how you use the drive, that is, which motor
control mode and which motor stop mode you select.
If you have the vector control mode and motor ramp stop selected, open the contactor as
follows:
1. Give a stop command to the drive.
2. Wait until the drive decelerates the motor to zero speed.
3. Open the contactor.
If you have the vector control mode and motor coast stop, or scalar control mode selected,
open the contactor as follows:
1. Give a stop command to the drive.
2. Open the contactor.
82 Guidelines for planning the electrical installation