Mitsubishi Electric 800 Series, Instruction Manual, Page: 634 / 727

Causes and corrective actions
PROTECTIVE FUNCTIONS
633
6 5
Abbreviation RB
FR-LU08
FR-PU07
RB
Name
Regenerative brake pre-alarm (Standard models only)
Description
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 (E. OV[ ]) occurs.
Check point
• Check if the brake resistor duty is not too high.
• Check that the
Pr.30 Regenerative function selection and Pr.70 settings are correct.
Corrective action
• Set the deceleration time longer.
• Check the
Pr.30 and Pr.70 settings. (Refer to page 608 .)
Abbreviation TH
FR-LU08
FR-PU07
TH
Name
Electronic thermal relay function pre-alarm
Description
Appears if the cumulative value of the electronic thermal O/L relay reaches or exceeds 85% of the preset
level of
Pr.9 Electronic thermal O/L relay . If the specified value is reached, the protection circuit is activated
to shut off the inverter output.
Check point
• Check for large load or sudden acceleration.
• Check that the
Pr.9 setting is appropriate. (Refer to page 317 .)
Corrective action
• Reduce the load and frequency of operation.
• Set an appropriate value in
Pr.9 . (Refer to page 317 .)
Abbreviation PS
FR-LU08
FR-PU07
PS
Name
PU stop
Description
• The motor is stopped using under the mode other than the PU operation mode. (To enable
under the mode other than the PU operation mode, set Pr.75 Reset selection/disconnected PU
detection/PU stop selection . Refer to page 244 for details.)
• The motor is stopped by the emergency stop function.
Check point
• Check for a stop made by pressing of the operation panel.
• Check for whether the X92 signal is OFF.
Corrective action
• Turn the start signal OFF and release with .
• Turn ON the X92 signal and OFF the start signal for release.
Abbreviation SL
FR-LU08
FR-PU07
SL
Name
Speed limit indication
Description
Output if the speed limit level is exceeded during torque control.
Check point
• Check that the torque command is not larger than required.
• Check if the speed limit level is set too low.
Corrective action
• Decrease the torque command value.
• Increase the speed limit level.
Abbreviation CP
FR-LU08
FR-PU07
CP
Name
Parameter copy
Description
Appears when parameter copy is performed between inverters FR-A860-01080 or lower, FR-A860-01440 or
higher
Check point
Resetting of Pr.9, Pr.30, Pr.51, Pr.56, Pr.57, Pr.61, Pr.70, Pr.72, Pr.80, Pr.82, Pr.90 to Pr.94, Pr.453, Pr.455,
Pr.458 to Pr.462, Pr.557, Pr.859, Pr.860 and Pr.893 is necessary.
Corrective action
Set the initial value in Pr.989 Parameter copy alarm release .
Abbreviation SA
FR-LU08 SA
FR-PU07 —
Name
SA
Description
Appears when the shorting wire across the terminals S1 and PC or the terminals S2 and PC is disconnected.
Check point
• Check if the shorting wire across the terminals S1 and PC or the terminals S2 and PC is disconnected.
Corrective action • Short across the terminals S1 and PC and the terminals S2 and PC with shortening wires.