Eaton PowerXL - Starting Single-Phase Motors

5 Operation
5.5 Commissioning with control signal terminals (default settings)
DC1-S…20…, DC1-S…OE1 Variable Frequency Drives 05/21 MN040058EN www.eaton.com 113
5.5.1 Starting single-phase motors
The speed of single-phase motors is essentially controlled the same way as
on three-phase motors: by adjusting the voltage and frequency.
The only difference is in how single-phase motors start.
While three-phase motors will follow the V/Hz curve from the beginning,
single-phase motors require a start boost.
Once a single-phase motor starts, the speed will be adjusted based on the
V/Hz curve, just like on three-phase motors.
① Voltage at desired speed
Voltage
• The voltage is increased linearly from V-Boost
(P-11) all the way to the rated motor operating
voltage (P-07) .
• The duration of the starting operation is defined
by t-Boost (P-33).
• After t-Boost (P-33) elapses, the voltage goes to
the value required for the desired speed under
consideration of the deceleration ramp set with
t-dec (P-04).
① Frequency at desired speed
Frequency
• The output frequency is constant during the
entire starting operation and is equal to f-Boost
(P-32).
• After t-Boost (P-33) elapses, the frequency goes
to the value required for the desired speed under
consideration of the deceleration ramp set with
t-dec (P-04).
U
P-07
t
①
P-11
P-33 P-04
f
P-32
t
①
P-33 P-04