2 Engineering
2.9 Three-phase motor
DA1 Variable Frequency Drives
08/18 MN04020005Z-EN
www.eaton.com
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2.9 Three-phase motor
2.9.1 Motor selection
Please note the following general recommendations for the motor selection:
•
Use three-phase induction motors with squirrel-cage rotors and surface
cooling – also referred to as three-phase asynchronous motors or
standard motors. Other types of motors, such as external rotor motors,
wound rotor motors, reluctance motors, permanent magnet motors,
synchronous motors, and servomotors can also be run with DA1 variable
frequency drives, but will normally require additional engineering,
modifying the various parameters, and detailed information from the
motor manufacturer.
•
Only use motors of at least class F temperature rating
(155 °C maximum constant temperature).
•
Choose 4-pole motors
where possible (with synchronous speeds of: 1500 min
-1
at 50 Hz or
1800 min
-1
at 60 Hz).
•
Please observe the operating conditions for S1 operation (IEC 60034-1).
•
Do not oversize the motor, i. e., the motor should not be more than one
rating level higher than the rated motor output.
•
With undersizing, the motor output may only be one output level less
than the allocated output level (to ensure the motor protection).
With significantly smaller motor output, the “frequency control U/f)”
operating mode must be set (P4-01 = 2).
→
Check whether the DA1 variable frequency drive you selected
and the rated AC motor you will be using are compatible with
each other as per the corresponding voltage (mains and motor
voltage) and rated operational current.