Orientation Control; Overspeed Detection; Encoder Feedback Control; Encoder Signal Cable Breakage Detection - Mitsubishi Electric FR-A700 Manual

Pr.
Pr.
350 to 366, 369, 393, 396 to 399

Orientation control

V/F V/F V/F
Pr.350 Stop position command selection
Pr.352 Creep speed
Pr.354 Position loop switchover position
Pr.356 Internal stop position command
Pr.358 Servo torque selection
Pr.360 16 bit data selection
Pr.362 Orientation position loop gain
Pr.364 Encoder stop check time
Pr.366 Recheck time
Pr.393 Orientation selection
Pr.397 Orientation speed integral time
Pr.399 Orientation deceleration ratio
This function is used with a position detector (encoder) installed to
the spindle of a machine tool, etc. to allow a rotation shaft to be
stopped at the specified position (oriented).
Plug-in option FR-A7AP is necessary.
Internal stop position command
When "0" is set in Pr.350 Stop position command selection, the inverter
operates in the internal stop position command mode.
In the internal stop position command mode, the setting value of Pr.
356 Internal stop position command becomes a stop position.
External stop position command
When 1 is set in Pr.350 Stop position command selection and the option
FR-A7AX is mounted, set a stop position using 16-bit data.
Action time chart
Spindle speed
(encoder)
0
Start signal (across STF/STR-SD)
OFF
Orientation command
(across X22-SD)
Current position signal
Origin signal
DC injection brake
In-position signal
(across ORA-SE)
Pr.
Pr.
359, 367 to 369

Encoder feedback control

Pr.359 Encoder rotation direction
Pr.368 Feedback gain
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 it back to the inverter.
Option FR-A7AP is necessary.
Set the rotation direction of the encoder using Pr.359 Encoder rotation
direction and Pr.369 Number of encoder pulses.
When a value other than "9999" is set in Pr.367 Speed feedback range,
encoder feedback control is valid.
Using the set point (frequency at which stable speed operation is
performed) as reference, set the higher and lower setting range.
Normally, set the frequency converted from the slip amount (r/min)
of the rated motor speed (rated load). If the setting is too large,
response becomes slow.
Driven load
Speed feedback range
Set value
(Set command)
Set Pr.368 Feedback gain when the rotation is unstable or response is
slow.
Pr.368 Setting
Although the response becomes faster, overcurrent or
Pr.368 > 1
unstable rotation is liable to occur.
Although the response becomes slower, the motor rotation
1 < Pr.368
becomes stable.
When setting parameters, refer to the instruction manual (applied) and understand instructions.
Magnetic flux Magnetic flux Magnetic flux Vector Vector Vector
Pr.351 Orientation speed
Pr.353 Creep switchover position
Pr.355 DC injection brake start position
Pr.357 In-position zone
Pr.359 Encoder rotation direction
Pr.361 Position shift
Pr.363 Completion signal output delay time
Pr.365 Orientation limit
Pr.369 Number of encoder pulses
Pr.396 Orientation speed gain (P term)
Pr.398 Orientation speed gain (D term)
Orientation speed (set in Pr. 351 )
Creep speed (set in Pr. 352 )
OFF
ON
OFF
ON
Creep select position
(set in Pr. 353 )
Position loop select position
(set in Pr. 354 )
DC injection
brake start position
Stop position command
(set in Pr. 355 )
OFF OFF
ON
OFF OFF
ON
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux
Pr.367 Speed feedback range
Pr.369 Number of encoder pulses
Regenerative load
Description
Pr.
Pr.
374

Overspeed detection

V/F V/F V/F
Pr.374 Overspeed detection level
When the motor speed reaches or exceeds the speed set in Pr.374
during encoder feedback control or vector control, overspeed
(E.OS) occurs and stops the inverter output.
Motor speed
Pr.374
ALM
Pr.
Pr.
376

Encoder signal cable breakage detection

V/F V/F V/F
Pr.376 Open cable detection enable/disable selection
When the cable of the encoder signal is broken during encoder
feedback control, orientation control, or vector control, open cable
detection (E.ECT) is activated to stop the inverter output.
Pr.
Pr.
380 to 383
Refer to the section about Pr.29.
Pr. Pr.
384 to 386
Refer to the section about Pr.291.
Magnetic flux Magnetic flux Magnetic flux Vector Vector Vector
Coast to stop
Time
ON
E.OS
Magnetic flux Magnetic flux Magnetic flux Vector Vector Vector
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