4 APPLICABLE FUNCTIONS
4.5 Machine diagnosis
253
4
■Threshold setting method
When the automatic threshold setting is used, [Pr. PF54 Friction failure prediction - Average characteristic] and [Pr. PF55
Friction failure prediction - Standard deviation] for determining the threshold value are automatically rewritten according to the
dynamic friction (at rated speed) estimated inside the servo amplifier. At this time, the threshold can be changed with [Pr.
PF52.0 Friction failure prediction - Threshold multiplication]. If [AL. 0F7.2 Friction failure prediction warning] is generated with
the value calculated by the automatic threshold setting, set [Pr. PF52.0 Friction failure prediction - Threshold multiplication] to
"6" or more. After the threshold is calculated in the servo amplifier, [Pr. PF51.0 Friction failure prediction warning selection]
changes to "2" (manual threshold setting).
For the manual threshold setting, the upper and lower limit thresholds can be calculated with the equations below. When [Pr.
PF52.0 Friction failure prediction - Threshold multiplication] is "0", the upper and lower limit thresholds are calculated as "5".
Upper limit threshold [0.1 %] = [Pr. PF54] + [Pr. PF55] × [Pr. PF52.0]
Lower limit threshold [0.1 %] = [Pr. PF54] - [Pr. PF55] × [Pr. PF52.0]
■Threshold reset method
To automatically reset thresholds after the upper and lower limit thresholds are set automatically, set [Pr. PF51.0 Friction
failure prediction warning selection] to "3" (threshold reset), then cycle the power. After cycling the power, the threshold value
is reset, and [Pr. PF51.0 Friction failure prediction warning selection] changes to "1" (threshold value automatic setting). If the
equipment parts are replaced after starting the friction failure prediction function, reset the friction thresholds and servo motor
total travel distance.
To Next Page
Loading...
