Mitsubishi Electric F700 Instruction Manual page 238

(2) Warnings
When the protective function is activated, the output is not shut off.
Operation Panel
Indication
Name Stall prevention (overcurrent)
During
acceleration
During
constant-
Description
speed
operation
During
deceleration
1. Check that the Pr. 0 Torque boost setting is not too large.
2. Check that the Pr. 7 Acceleration time and Pr. 8 Deceleration time settings are not too small.
3. Check that the load is not too heavy.
Check point
4. Are there any failure in peripheral devices?
5. Check that the Pr. 13 Starting frequency is not too large.
1. Increase or decrease the Pr. 0 Torque boost setting 1% by 1% and check the motor status. (Refer to page 53.)
2. Set a larger value in Pr. 7 Acceleration time and Pr. 8 Deceleration time. (Refer to page 74.)
3. Reduce the load weight.
4. Try simple magnetic flux vector control (Pr. 80).
Corrective action 5. Change the Pr. 14 Load pattern selection setting.
6. Set stall prevention operation current in Pr. 22 Stall prevention operation level. (The initial value is 110%.)
*1 120% when LD is selected
Operation Panel
Indication
Name
Stall prevention (overvoltage)
During
Description
deceleration
· Check for sudden speed reduction.
Check point
· Regeneration avoidance function (Pr. 882 to Pr. 886) is being used? (Refer to page 139.)
The deceleration time may change.
Corrective action
Increase the deceleration time using Pr. 8 Deceleration time.
Operation Panel
Indication
Name Regenerative brake prealarm
Appears if the regenerative brake duty reaches or exceeds 85% of the Pr. 70 special regenerative
brake duty value. If the regenerative brake duty reaches 100%, a regenerative overvoltage
Description
(E. OV_) occurs.
Appears only for the 01800 or more.
• Check that the brake resistor duty is not high.
Check point
• Check that the Pr. 30 Regenerative function selection and Pr. 70 Special regenerative brake duty values
• Increase the deceleration time.
Corrective action
• Check the Pr. 30 Regenerative function selection and Pr. 70 Special regenerative brake duty values.
OL
If a current of more than 110%
function stops the increase in frequency until the overload current reduces to
prevent the inverter from resulting in overcurrent shut-off.
When the overload current has reduced below 110%
frequency again.
If a current of more than 110%
function lowers the frequency until the overload current reduces to prevent
overcurrent shut-off. When the overload current has reduced below 110%
function increases the frequency up to the set value.
If a current of more than 110%
function stops the decrease in frequency until the overload current reduces to
prevent the inverter from resulting in overcurrent shut-off.
When the overload current has reduced below 110%
frequency again.
· Check the motor for use under overload.
The 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.
(Use Pr. 156 to set either operation continued or not at OL operation.)
oL
· If the regenerative energy of the motor becomes excessive and exceeds the
regenerative energy consumption capability, this function stops the decrease in
frequency to prevent overvoltage shut-off. 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 shut-off. (Refer to page 139.)
RB
are correct.
Causes and corrective actions
FR-PU04 OL
of the rated inverter current flows in the motor, this
*1
, this function increases the
*1
of the rated inverter current flows in the motor, this
*1
of the rated inverter current flows in the motor, this
*1
, this function decreases the
*1
FR-PU04 oL
FR-PU04 RB
, this
*1
4
231