Omron RX Series - Adjustment for Sensor Vector Control (Speed Control)

6 Vector Control
6 - 26
High-function General-purpose Inverter 3G3RX-V1 User’s Manual (I578-E1)
• To use the sensor vector control method, perform offline auto-tuning.
If you cannot perform offline auto-tuning, set the motor parameters appropriately according to 6-3-5
Motor Parameter Settings on page 6-24.
• After completion of auto-tuning, set the V2 Control Mode Selection (P012) to 00 (Speed control) to
adjust the motor parameter values.
• The inverter may not provide sufficient performance characteristics if you motor is two or more sizes
smaller than the maximum applicable motor capacity.
• If acceleration is abnormal, or if an Encoder disconnection (E60. / E70. ) or Overspeed
(E61. /E71. ) error occurs, check the encoder wiring and the parameter settings for the PG Board.
• If sensor vector control cannot provide the desired characteristics, adjust the motor parameters
depending on the phenomena, as shown in the table below.
Precautions for Correct UsePrecautions for Correct Use
• Be sure to set the Carrier Frequency (b083) to 2.1 kHz or higher. The inverter will not operate
normally at 2.1 Hz or lower.
• To use a motor one size smaller in capacity than the inverter, set the Torque Limit 1 to 4 (b041
to b044) to the value calculated by using the following formula. Be sure that the value α is not
more than 200%. Otherwise, the motor may burn out.
α = Torque Limit set value x (Inverter capacity) / (Motor capacity)
Example
To result in α = 200% when the inverter capacity is 0.75 kW and the motor capacity is 0.4 kW,
according to the above formula, the Torque Limit set value (b041 to b044) can be calculated as
follows: α x (Motor capacity) / (Inverter capacity) = 200% x (0.4 kW) / (0.75 kW) = 106%.
6-3-6 Adjustment for Sensor Vector Control (Speed Control)
Operation
status
Phenomenon Adjustment method
Adjustment
item
During startup
Shock occurs during
startup.
Decrease the Motor Parameter J value
gradually, relative to the set value.
H024/H034
During
deceleration
Motor is hunting.
Decrease the Speed Response value. H005
Decrease the Motor Parameter J value
gradually, relative to the set value.
H024/H034
During torque
limit
Torque becomes
insufficient at low
frequencies when torque
limit is enabled.
Set the Overload Limit Level to a value lower
than the Torque Limit.
b021/
b041 to b044
Low-frequency
operation
Rotation is unstable.
Increase the Motor Parameter J value, relative
to the set value.
H024/H034