Artesis AMT Toolkit, Руководство пользователя

Страница: 27 / 78

AMU Use
25
3.4.5.4. Alarms during the IMPROVE mode
Alarm conditions may occur during any monitoring phase. If CHECK MOTOR has previously
been run on the motor, it is likely that the alarms represent transient conditions present on
the power lines. However, it is suggested that any alarm representing a condition that could
affect the performance of the motor should be recorded and investigated as a potential
cause of motor degradation. As in CHECK MOTOR, if an alarm is indicated, the most recent
physical values available for the motor can be displayed using the UP and DOWN buttons.
Examination of these values can often indicate the precise reason for the alarm condition. A
complete list of alarm conditions can be found in the appendix at the end of this manual.
3.4.5.5. Using an inverter drive
If an inverter is being used to drive the motor, several additional precautions are needed.
The voltage frequency is expected to be constant (within well-defined limits) for direct line
driven motors, but can vary considerably when an inverter is used. AMU can handle the
range of frequencies typical of an inverter, but first needs to learn the motor at a single
frequency representative of the conditions it will meet in practice. The value of this
dominant frequency must be entered from the Edit Settings menu. If AMU measures the
frequency to be out of the expected range, it will issue an alarm in both the CHECK MOTOR
and LEARN modes and the user should adjust the frequency setting accordingly. During
IMPROVE mode this requirement is relaxed and the frequency can assume any value within
the allowed frequency range.
NOTE
AMU is not suitable for the following applications:

If motor supply voltage is changing over 15% in
6 seconds.

If motor current is changing over 15% in 6
seconds.

DC motors

If motor is driven by an inverter whose
chopping frequency is under 2 kHz.