Mitsubishi Electric FR-D720-0.2K-G Instruction Manual page 258

Operation panel
Err.
indication
Name
Drive unit reset
 Executing reset using RES signal, or reset command from communication or PU
Description
 Displays at powering OFF.
Corrective action
 Turn OFF the reset command
(2) Warning
When a warning occurs, the output is not shut off.
Operation panel
OL
indication
Name Stall prevention (overcurrent)
During
acceleration
During
constant-
Description
speed
operation
During
deceleration
 Check that the Pr. 7 Acceleration time and Pr. 8 Deceleration time settings are not too small.
 Check that the load is not too heavy.
Check point  Are there any failure in peripheral devices?
 Check that the Pr. 22 Stall prevention operation level is appropriate
 Check if the operation was performed without connecting a motor.
 Set a larger value in Pr. 7 Acceleration time and Pr. 8 Deceleration time. (Refer to page 97.)
 Reduce the load weight.
 Check the peripheral devices.
 Set stall prevention operation current in Pr. 22 Stall prevention operation level. (The initial value is 150%.) The
Corrective action
acceleration/deceleration time may change. Increase the stall prevention operation level with Pr. 22 Stall prevention
operation level, or disable stall prevention with Pr. 156 Stall prevention operation selection. (Operation at OL
occurrence can be selected using Pr. 156.)
 Check the connection of the PM motor.
Operation panel
oL
indication
Name Stall prevention (overvoltage)
During
Description
deceleration
 Check for sudden speed reduction.
Check point
 Check that regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886) is used. (Refer to page 228.)
Corrective action Increase the deceleration time using Pr. 8 Deceleration time.
FR-PU07
When the output current of the drive unit exceeds the stall prevention operation level (Pr. 22 Stall
prevention operation level, etc.), this function stops the increase in speed until the overload current
decreases to prevent the drive unit from resulting in overcurrent trip. When the overload current has
reduced below stall prevention operation level, this function increases the speed again.
When the output current of the drive unit exceeds the stall prevention operation level (Pr. 22 Stall
prevention operation level, etc.), this function reduces speed until the overload current decreases to
prevent the drive unit from resulting in overcurrent trip. When the overload current has reduced below
stall prevention operation level, this function increases the speed up to the set value.
When the output current of the drive unit exceeds the stall prevention operation level (Pr. 22 Stall
prevention operation level, etc.), this function stops the decrease in speed until the overload current
decreases to prevent the drive unit from resulting in overcurrent trip. When the overload current has
decreased below stall prevention operation level, this function decreases the speed again.
FR-PU07
 If the regenerative energy of the motor becomes excessive to exceed the regenerative energy
consumption capability, this function stops the decrease in speed to prevent overvoltage trip. As
soon as the regenerative energy has reduced, deceleration resumes.
 If the regenerative energy of the motor becomes excessive when regeneration avoidance function
is selected (Pr. 882 = 1), this function increases the speed to prevent overvoltage trip.
(Refer to page 228.)
Causes and corrective actions
OL
oL
5
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