Mitsubishi Electric MELSERVO-J4 series, Instruction Manual

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7 SPECIAL ADJUSTMENT FUNCTIONS
7.3 Tough drive function
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Instantaneous power failure tough drive function
The instantaneous power failure tough drive function avoids [AL. 10 Undervoltage] even when an instantaneous power failure
occurs during operation. When the instantaneous power failure tough drive activates, the function will increase the tolerance
against instantaneous power failure using the electrical energy charged in the capacitor in the servo amplifier and will change
an alarm level of [AL. 10 Undervoltage] simultaneously. The [AL. 10.1 Voltage drop in the control circuit power] detection time
for the control circuit power supply can be changed by [Pr. PF25 SEMI-F47 function - Instantaneous power failure detection
time]. In addition, [AL. 10.2 Voltage drop in the main circuit power] detection level for the bus voltage is changed automatically.
• MBR (Electromagnetic brake interlock) will not turn off during the instantaneous power failure tough drive.
• When selecting "Enabled (_ _ _ 1)" for "Torque limit function selection at instantaneous power failure" in [Pr.
PA26], if an instantaneous power failure occurs during operation, you can save electric energy charged in
the capacitor in the servo amplifier by limiting torque at acceleration. You can also delay the time until the
occurrence of [AL. 10.2 Voltage drop in the main circuit power]. Doing this will enable you to set a longer
time in [Pr. PF25 SEMI-F47 function - Instantaneous power failure detection time].
• When the load of instantaneous power failure is large, [AL. 10.2] caused by the bus voltage drop may occur
regardless of the set value of [Pr. PF25 SEMI-F47 function - Instantaneous power failure detection time].
• The external dynamic brake cannot be used for compliance with SEMI-F47 standard. Do not assign DB
(Dynamic brake interlock) in [Pr. PD07] to [Pr. PD09]. Failure to do so will cause the servo amplifier to
become servo-off when an instantaneous power failure occurs.
• To comply with SEMI-F47 standard, it is unnecessary to change the initial value (200 ms) in [Pr. PF25
SEMI-F47 function - Instantaneous power failure detection time]. When the instantaneous power failure
time exceeds 200 ms, and the instantaneous power failure voltage is less than 70% of the rated input
voltage, the power may be normally turned off even if a value larger than 200 ms is set in the parameter.