1-22
IM WT3001E-51EN
• Selecting the Frequency Measurement Source Signal (Voltage or
Current Signal Supplied to the Motor)
2.
Press the
cursor keys
to select Sync Speed Source.
3.
Press
SET
. A frequency measurement source selection box appears.
4.
Press the
cursor keys
to select any of the target input signals for frequency
measurement (see section 5.3 in the
User’s Manual IM WT3001E-01EN
).
When the button to the left of the input signal in the selection box is highlighted,
that is the source input signal for frequency measurement selected in section 5.3
in the
User’s Manual IM WT3001E-01EN
.
5.
Press
SET
to confirm the frequency measurement source.
Explanation
• Setting the Motor’s Number of Poles
The number can be set in the range of 1 to 99. Sets the number of poles for the motor
being measured.
• Setting the Frequency Measurement Source Signal
• Select the frequency measurement source from the choices below. The selectable
items vary depending on the installed elements.
U1, I1, U2, I2, U3, I3, U4, and I4
• Select any of the source input signals for frequency measurement. When the button
to the left of the input signal in the frequency measurement source selection box is
highlighted, that is the source input signal for frequency measurement selected in
section 5.3 in the
User’s Manual IM WT3001E-01EN
. If you select an input signal
that is not a frequency measurement source, an error results.
• In normal cases, the frequency measurement source (see section 5.3 in the
User’s
Manual IM WT3001E-01EN
) is set to the voltage or current supplied to the motor.
If a frequency other than that of the voltage and current supplied by the motor is
specified, the synchronous speed may not be determined correctly.
• Equation for Deriving the Synchronous Speed
The unit of synchronous speed is fixed to min
–1
(or rpm). The equation is indicated
below.
120 × frequency of the frequency measurement source (Hz)
Motor’s number of poles
Rotating speed SyncSp (min
–1
) =
1.8 Setting the Motor and Frequency Measurement Source for Computing the Sync Speed and Slip