Toshiba VF-AS1 Power Supply User Manual


 
E6581528
F-60
6
6.33.13 Abnormal speed detection
 : Abnormal speed detection time
 : Overspeed detection frequency upper band
 : Overspeed detection frequency lower band
• Function
These parameters allow you to set the inverter so that, when it is in sensor speed control mode (=,
), it always monitors the rotational speed of the motor, even when the motor is at rest, and if the speed
remains out of the specified limits for the specified length of time, it outputs an error signal.
Title Function Adjustment range Default setting
 Abnormal speed detection time ~ sec. 
 Overspeed detection frequency upper band : Disabled, ~ Hz 
 Overspeed detection frequency lower band : Disabled, ~ Hz 
Output frequency [Hz]
Time [s]
0
Output frequency
 trip




Note 1: This function doesn't operate at the time of a torque control.
Note 2: It is advisable to set the parameter  (Acceleration/deceleration operation after torque limit) to when
this function is set.
6.33.14 Overvoltage limit operation
 : Overvoltage limit operation level
For more details, refer to Section 6.14.2.
6.33.15 Undervoltage trip
 : Undervoltage detection level
 : Undervoltage trip selection
 : Undervoltage (trip alarm) detection time
• Function
This parameter is used for selecting the control mode when an undervoltage is detected. (Invalid, while the
inverter stops.) When selecting “tripping enabled,” you can also specify the time elapsed before the inverter trips.
=: (Disabled) ··············· Inverter stops,but does not trip. (FL is not active.)
=: (Enabled) ················ The inverter trips  if an undervoltage passes for the time set with  or
over. (FL is activated.)
Title Function Adjustment range Default setting
 Undervoltage detection level
~ % for 500V class.
~ % for 575V class
~ % for 690V class
,  %: (auto mode)
According to voltage
class
Refer to page
K-23.
 Undervoltage trip selection : Disabled, : Enabled 
 Undervoltage (trip alarm) detection time ~ sec. 