Three-Phase Motors; Motor Selection - Eaton PowerXL DB1 Installation Manual

2.8 Three-phase motors

2.8.1 Motor selection

DB1 variable frequency drives can be used to drive the following three-phase
AC motors with sensorless control:
• Three-phase asynchronous motor (DAM),
• Permanent magnet motor (PM),
• Brushless DC motors (BLDC),
• Synchronous reluctance motor (SynRM).
When delivered, the DB1 variable frequency drive is set with U/f modulation
for the assigned motor output of a three-phase asynchronous motor.
￫
Vector mode, as well as running PM, BLDC, or SyncRM motors,
will need parameters P-60 and P-61 on DB1 variable frequency
drives to be configured accordingly.
￫
Check whether your chosen DB1 variable frequency drive, in
terms of its cooling, is compatible with the assigned three-
phase AC motor in terms of voltage (mains and motor voltage)
and the rated current.
Configurations such as the ones used in outrunner motors and slip-ring
motors also fall under the three-phase asynchronous motor category (which
in turn is also referred to as the "squirrel-cage rotor" or "standard motor"
category). These motors can also be run with DB1 variable frequency drives,
but will normally require additional engineering, modifying the various param-
eters, and detailed information from the motor manufacturer.
General recommendations for motor selection:
• Only use motors of at least class F temperature rating
(155 °C maximum constant temperature).
• Chose four-pole motors
where possible (with synchronous speeds of: 1500 min
-1
1800 min 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.
• In the case of undersized motors, the motor output for continuous oper-
ation should not be more than one rating level lower than the rated rating
level (in order to ensure that the motor will be protected).
• When running tests or commissioning a system with significantly lower
motor outputs, the motor's rated current must be adjusted using para-
meter P-08 ("Motor Nom Current").
DB1 Variable Frequency Drives 09/17 MN040031EN www.eaton.com
2 Engineering
2.8 Three-phase motors
-1
at 50 Hz or
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