Mitsubishi Electric MR-J5 Series User Manual page 170

Static friction failure prediction function [G] [WG]
■Friction failure prediction function method of use
Follow these procedures when using the static friction failure prediction function. For the static friction failure prediction
function, threshold that outputs a warning can be calculated automatically inside the servo amplifier using the automatic
threshold setting or set with servo parameters using the manual threshold setting. With the manual threshold setting, the
threshold that outputs a warning can be set to any value.
Set [Pr. PF34.5 Static friction failure prediction warning
selection] to "2" (Manual threshold setting).
Drive the servo motor.
The static friction and dynamic friction (at rated speed) are
estimated.
Save the data of the estimated static friction and dynamic friction.
Set a threshold with the following servo parameters.
[Pr. PF69 Static friction failure prediction - Average
characteristics]
[Pr. PF70 Static friction failure prediction - Standard deviation]
[Pr. PF40.4 Static friction failure prediction - Threshold
multiplication]
The setting of [Pr. PF40.5 Static friction failure prediction - Static
friction selection] is changed depending on the operation pattern.
Has the servo motor total travel
distance exceeded the value of
[Pr. PF41 Failure prediction -
Servo motor total travel distance]?
4 APPLICABLE FUNCTION
168
4.3 Machine diagnosis
Start
Startup the system.
When the maximum operation speed is under the rated
speed, set half the value of the maximum operation speed
in [Pr. PF31].
Which function?
Friction failure prediction function
Set [Pr. PF41 Failure prediction - Servo motor total travel
distance] based on the initial stretch characteristics
presented by respective belt manufacturer.
Threshold setting method?
Manual threshold setting Automatic threshold setting
Set [Pr. PF34.5 Static friction failure prediction warning
selection] to "1" (Automatic threshold setting).
Drive the servo motor.
The static friction and dynamic friction (at rated speed) are
estimated.
*1
Save the data of the estimated static friction and dynamic friction.
The setting of [Pr. PF40.5 Static friction failure prediction - Static
friction selection] is changed depending on the operation pattern.
NO
The threshold is automatically calculated.
The settings of [Pr. PF69 Static friction failure prediction - Average
characteristics] and [Pr. PF70 Static friction failure prediction -
Standard deviation] are changed based on the data of the
YES
estimated dynamic friction.
[Pr. PF34.5 Static friction failure prediction warning
selection] is set to "2" (Manual threshold setting).
Friction failure prediction is performed. If the dynamic
friction value exceeds the threshold range, [AL. 0F7
Machine diagnosis warning] will occur.
End
Friction estimation function
Drive the servo motor.
The static friction and dynamic friction (at rated speed) are
estimated.
Save the data of the estimated static friction and dynamic friction.
Has the servo motor total travel
distance exceeded the value of
[Pr. PF41 Failure prediction -
Servo motor total travel distance]?
YES
*2
Has a threshold been created?
YES
*1
*1 The saved data of static friction and dynamic friction
is used for troubleshooting [AL. 0F7.5 Static friction
failure prediction warning].
NO
To calculate the threshold, after frictions have been
estimated, the equipment must be operated for 3
consecutive hours or more and operated in the
position mode, or velocity mode for a cumulative
time of 90 hours or more.
NO
Aging of the equipment is
estimated by comparing the
saved data of static friction
and dynamic friction with the
data being read while the
equipment is in operation.