Mitsubishi Electric FR-E800, Instruction Manual

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16. (G) Control Parameters
16.11 Encoder feedback control
16.11
Encoder feedback control
This controls the inverter output frequency so that the motor speed is constant to the load variation by detecting the motor
speed with the speed detector (encoder) to feed back to the inverter.
A Vector control compatible option is required.
*1 The speed deviation excess detection frequency is used under Vector control or PM sensorless vector control. (Refer to page 130 for details.)
*2 The setting is available when a Vector control compatible option is installed.
 Setting before operation (Pr.359, Pr.369)
• Use Pr.359 Encoder rotation direction and Pr.369 Number of encoder pulses to set the rotation direction and the
number of pulses for the encoder.
NOTE
• Control with correct speed is not possible if the number of poles for the applied motor is incorrect. Check first before operation.
• Encoder feedback control is not possible when the rotation direction setting of the encoder is incorrect. (Operation of the
inverter is possible.)
Check the indicator on the parameter unit to confirm the direction.
 Selection of encoder feedback control (Pr.367)
• When a value other than "9999" is set in Pr.367 Speed feedback range , encoder feedback control is enabled. Set a target
value (frequency at which stable speed operation is performed) and specify the range around the value. Normally, use the
frequency converted from the slip amount (r/min) at the rated motor speed (rated load). If the setting is too large, response
becomes slow.
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux
Pr. Name
Initial
value
Setting range Description
285
A107
Overspeed detection
frequency
*1
9999
0 to 30 Hz
E.MB1 (Brake sequence fault) occurs when the difference
between the detection frequency and output frequency
exceeds the setting value under encoder feedback control.
9999 Overspeed detection is disabled.
359
*2
C141
Encoder rotation direction 101
100
Set when using a motor (encoder) for which forward rotation is
clockwise (CW) viewed from the shaft.
101
Set when using a motor for which forward rotation (encoder) is
counterclockwise (CCW) viewed from the shaft.
367
*2
G240
Speed feedback range 9999
0 to 590 Hz Set the range of speed feedback control.
9999 The encoder feedback control is disabled.
368
*2
G241
Feedback gain 1 0 to 100 Set when the rotation is unstable or response is slow.
369
*2
C140
Number of encoder pulses 1024 2 to 4096
Set the number of encoder pulses.
Set the number of pulses before it is multiplied by 4.
376
*2
C148
Encoder signal loss detection
enable/disable selection
0
0 Signal loss detection is disabled.
1 Signal loss detection is enabled.
CW
CCW
Speed feedback range
Set value
(Set command)
Driven load Regenerative load