Mitsubishi Electric MELSERVO-J4 series, Инструкция по эксплуатации

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17 APPLICATION OF FUNCTIONS
17.5 Machine diagnosis function
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17
Vibration failure prediction function
The vibration failure prediction function predicts a failure of the equipment from the increase in the vibration level estimated by
the vibration estimation function. If a failure of the equipment is predicted from the vibration level, [AL. F7.1 Vibration failure
prediction warning] will occur.
In the vibration failure prediction function, a threshold that triggers [AL. F7.1] can be set by the following two methods.
■
Automatic threshold setting
From the vibration level estimated by the vibration estimation function, a threshold that triggers [AL. F7.1] is automatically
calculated in the servo amplifier. With this setting, you can use the vibration failure prediction function without setting a
threshold. However, after the vibration failure prediction function operates, the equipment must be operated for about 90
hours before vibration failure prediction is actually performed. [AL. F7.1] does not occur until a threshold is calculated in the
servo amplifier.
■ Manual threshold setting
You can set a threshold that triggers [AL. F7.1 Vibration failure prediction warning] with "Vibration failure prediction -
Threshold multiplication (_ _ x _)" in [Pr. PF40], and with [Pr. PF45 Vibration failure prediction - Average characteristic] and
[Pr. PF46 Vibration failure prediction - Standard deviation]. For the manual threshold setting, vibration failure prediction will
start immediately after the vibration failure prediction function operates. Thus, if the vibration amplitude threshold is known, or
the equipment you use is configured the same as another piece of equipment used for calculating the threshold with the
automatic threshold setting, an initial failure or others can also be detected with the manual threshold setting.
The vibration failure prediction function can be used with the following procedure.
■
Vibration failure prediction warning setting
To enable the vibration failure prediction warning, set "Vibration failure prediction warning selection (_ _ x _)" in [Pr. PF34] to
"_ _ 1 _ (automatic threshold setting)" or "_ _ 2 _ (manual threshold setting)".
■
Threshold setting method
For the automatic threshold setting, [Pr. PF45 Vibration failure prediction - Average characteristic] and [Pr. PF46 Vibration
failure prediction - Standard deviation] for determining a threshold are automatically rewritten according to the vibration level
estimated in the servo amplifier. At this time, changing "Vibration failure prediction - Threshold multiplication (_ _ x _)" in [Pr.
PF40] enables to change the threshold. If [AL. F7.1 Vibration failure prediction warning] occurs with the value obtained by the
automatic threshold setting, set "_ _ 6 _" or more in [Pr. PF40 (_ _ x _)]. After the threshold is calculated in the servo amplifier,
[Pr. PF34 (_ _ x _)] will be set to "_ _ 2 _ (manual threshold setting)".
For the manual threshold setting, the upper and lower limit thresholds can be calculated with the equation below. When [Pr.
PF40 (_ _ x _)] is set to "_ _ 0 _", a threshold is calculated assuming the setting as "_ _ 5 _".
Threshold [0.1%] = [Pr. PF45 Vibration failure prediction - Average characteristic] + [Pr. PF46 Vibration failure prediction -
Standard deviation]

"Vibration failure prediction - Threshold multiplication (_ _ x _)" in [Pr. PF40]
The values of [Pr. PF45 Vibration failure prediction - Average characteristic] and [Pr. PF46 Vibration failure prediction -
Standard deviation] can also be determined by measuring the torque ripple with the graph function of MR Configurator2. By
setting the average and standard deviation of the torque ripple, which are measured by the graph function, in [Pr. PF45] and
[Pr. PF46], you can also set the threshold for vibration failure prediction.
0 0 0
[Pr. PF34]
Vibration failure prediction warning selection
0: Disabled
1: Automatic threshold setting
2: Manual threshold setting
3: Threshold reset