Mitsubishi Electric MR-J4W2, Instruction Manual

Page: 342 / 542

15. USING A DIRECT DRIVE MOTOR
15 - 15
15.3.4 Function
(1) Servo control error detection function
POINT
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].
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
Figure 15.1 Outline of servo control error detection function
(a) Position deviation error detection
Set [Pr. PL04] to "_ _ _ 1" to enable the position deviation error detection.
[Pr. PL04]
Position deviation error detection enabled
1
When you compare the model feedback position ( 1)) and the feedback position ( 2)) in figure 15.1, 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 linear servo
motor will stop. The initial value of this detection level is 0.09 rev. Replace the set value as required.