Mitsubishi Electric FR-A700 EC, Инструкция по эксплуатации

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Causes and corrective actions Troubleshooting
7 - 8
Warnings
When the protective function is activated, the output is not shut off.
Operation Panel
Indication
OL
FR-PU04
FR-PU07
OL
Name Stall prevention (overcurrent)
Description
During
acceleration When the output current (output torque during real sensorless vector con-
trol or vector control) of the inverter exceeds the stall prevention operation
level (Pr. 22 "Stall prevention operation level", etc.), this function stops the
increase in frequency until the overload current decreases to prevent the
inverter from resulting in overcurrent shut-off. When the overload current
has decreased below stall prevention operation level, this function
increases the frequency again.
During
constant-
speed
operation When the output current (output torque during real sensorless vector
control or vector control) of the inverter exceeds the stall prevention
operation level (Pr. 22 "Stall prevention operation level", etc.), this
function reduces frequency until the overload current decreases to
prevent the inverter from resulting in overcurrent shut-off. When the
overload current has decreased below stall prevention operation
level, this function increases the frequency up to the set value.
During
deceleration When the output current (output torque during real sensorless vector con-
trol or vector control) of the inverter exceeds the stall prevention operation
level (Pr. 22 "Stall prevention operation level", etc.), this function stops the
decrease in frequency until the overload current decreases to prevent the
inverter from resulting in overcurrent shut-off. When the overload current
has decreased below stall prevention operation level, this function
decreases the frequency again
Check point
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.
4) Are there any failure in peripheral devices?
5) Check that the Pr. 13 "Starting frequency" is not too large.
앫
Check the motor for use under overload.
Corrective action
1) Increase or decrease the Pr. 0 "Torque boost setting" 1% by 1% and check the motor
status. (Refer to section 6.2.1.)
2) Set a larger value in Pr. 7 "Acceleration time" and Pr. 8 "Deceleration time". (Refer to
section 6.11.1.)
3) Reduce the load weight.
4) Try advanced magnetic flux vector control, real sensorless vector control or vector
control.
5) Change the Pr. 14 "Load pattern selection" setting.
6) Set stall prevention operation current in Pr. 22 "Stall prevention operation level". (The ini-
tial value is 110%.)
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.)
Operation Panel
Indication
oL
FR-PU04
FR-PU07
oL
Name Stall prevention (overcurrent)
Description
During
deceleration
앫
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 over voltage shut-off. As
soon as the regenerative energy has decreased, deceleration resumes.
앫
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 over voltage shut-off. (Refer to
section 6.24.8.)
Check point
앫
Check for sudden speed reduction.
앫
Regeneration avoidance function (Pr. 882 to Pr. 886) is being used? (Refer to
section 6.24.8).
Corrective action
The deceleration time may change. Increase the deceleration time using Pr. 8 "Decelera-
tion time".