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7. SPECIAL ADJUSTMENT FUNCTIONS
7.1.3 Instantaneous power failure tough drive function
CAUTION
During the instantaneous power failure tough drive, the torque may be limited due
to the load conditions or the set value of parameter No. PC28 (detailed setting of
instantaneous power failure tough drive).
The immunity to instantaneous power failures is increased by the instantaneous
power failure tough drive function. However, it is not compliant with the SEMI-F47
specification.
The instantaneous power failure tough drive function avoids the instantaneous power failure alarm even when
an instantaneous power failure occurs during operation. When the instantaneous power failure tough drive
activates, the immunity to instantaneous power failures is increased by using the electrical energy charged in
the main circuit capacitor during instantaneous power failures. The instantaneous power failure alarm judgment
time for the main circuit power can be changed by parameter No. PC28 (detailed setting of instantaneous
power failure tough drive).
POINT
The electromagnetic brake interlock (MBR) does not turn off during the
instantaneous power failure tough drive.
When the load of instantaneous power failure is heavy, the undervoltage alarm
(10.2) caused by the bus voltage drop may occur regardless of the setting value
of parameter No. PC28 (detailed setting of instantaneous power failure tough
drive).
(1) When the instantaneous main circuit power failure time is shorter than the set value of parameter No. PC28
(detailed setting of instantaneous power failure tough drive)
Main circuit
power supply
Bus voltage
Undervoltage
level (158VDC)
Trouble (ALM)
During tough
drive (MTTR)
Electromagnetic
brake interlock
(MBR)
Base circuit
ON
OFF
Instantaneous power failure time
of the main circuit power supply
When the power is returned within parameter
No. PC28 setting value, after disconnection of
the main circuit power supply, the instantaneous
power failure alarm of the main circuit (10.3) is
not generated.
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Parameter No. PC28
Electromagnetic brake interlock (MBR)
is not turned off.
When the instantaneous power failure tough drive function activates, the number of tough drive of the display
mode (alarm mode) is increased by one. (Refer to section 5.5.)