Mitsubishi Electric MELSERVO-J4 series, Instruction Manual

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15 USING A DIRECT DRIVE MOTOR
15.3 Operation and functions
Function
Servo control error detection function
For the servo control error detection function, the position and speed deviation error detections are enabled by
default. ([Pr. PL04]: _ _ _ 3)
If the servo control gets unstable for some reasons, the direct drive motor may not operate properly. To detect this state and to
stop operation, the servo control error detection function is used as a protective function.
The servo control error detection function has three different detection methods: the position deviation, speed deviation, and
torque deviation. An error is detected when each method is enabled with [Pr. PL04 Linear servo motor/DD motor function
selection 2]. The detection level can be changed with [Pr. PL05], [Pr. PL06], and [Pr. PL07].
■ Outline of servo control error detection function
■
Position deviation error detection
Set [Pr. PL04] to "_ _ _ 1" to enable the position deviation error detection.
When you compare the model feedback position ( 1)) and the feedback position ( 2)) in "Outline of servo control error
detection function", if the deviation is more than the value of [Pr. PL05 Position deviation error detection level] (1 (0.01 rev) to
1000 (10 rev)), [AL. 42.1 Servo control error by position deviation] will occur and the direct drive motor will stop. The initial
value of this detection level is 0.09 rev. Replace the set value as required.
For "Outline of servo control error detection function", refer to the following.

Page 506 Outline of servo control error detection function
■
Speed deviation error detection
Set [Pr. PL04] to "_ _ _ 2" to enable the speed deviation error detection.
When you compare the model feedback speed ( 3)) and the feedback speed ( 4)) in "Outline of servo control error detection
function", if the deviation is more than the value of [Pr. PL06 Speed deviation error detection level] (1 r/min to 2000 r/min), [AL.
42.2 Servo control error by speed deviation] will occur and the direct drive motor will stop. The initial value of this detection
level is 100 r/min. Replace the set value as required.
For "Outline of servo control error detection function", refer to the following.

Page 506 Outline of servo control error detection function
Servo amplifier internal value
1) Model feedback position [rev]
3) Model feedback speed [r/min]
5) Command torque [%]
Encoder
2) Feedback position [rev]
4) Feedback speed [r/min]
6) Feedback torque [%]
Servo amplifier
Direct drive motor
Encoder
[Pr. PL04]
Position deviation error detection enabled
1
[Pr. PL04]
Speed deviation error detection enabled
2