Mitsubishi Electric 800 Series Instruction Manual page 20

 Regenerative brake pre-alarm
Operation panel
indication
Description
Check point
Corrective action
Reference
 Electronic thermal relay function pre-alarm
Operation panel
indication
Description
Check point
Corrective action
Reference
 PU stop
Operation panel
indication
Description
Check point
Corrective action
Reference
 Speed limit indication (output during speed limit)
Operation panel
indication
Description
Check point
Corrective action
Reference
 Safety stop
Operation panel
indication
Description
Check point
Corrective action
Reference
19
2. Protective Functions
2.5 Causes and corrective actions
RB
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 if the brake resistor duty is not too high.
• Check that the Pr.30 Regenerative function selection and Pr.70 settings are correct.
• Set the deceleration time longer.
• Check the Pr.30 and Pr.70 settings.
FR-E800 Instruction Manual (Function)
TH
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 for large load or sudden acceleration.
• Check that the Pr.9 setting is appropriate.
• Reduce the load and frequency of operation.
• Set an appropriate value in Pr.9.
FR-E800 Instruction Manual (Function)
PS
• The motor is stopped using the STOP/RESET key under the mode other than the PU operation mode. (To
enable the STOP/RESET key under the mode other than the PU operation mode, set Pr.75 Reset selection/
disconnected PU detection/PU stop selection.
• The motor is stopped by the emergency stop function.
• Check for a stop made by pressing the STOP/RESET key on the operation panel.
• Check for whether the X92 signal is OFF.
• Turn OFF the start signal and press the PU/EXT key for release.
• Turn ON the X92 signal and OFF the start signal for release.
FR-E800 Instruction Manual (Function)
SL
Output if the speed limit level is exceeded during torque control.
• Check that the torque command is not larger than required.
• Check if the speed limit level is set too low.
• Decrease the torque command value.
• Increase the speed limit level.
FR-E800 Instruction Manual (Function)
SA
Appears when safety stop function is activated (during output shutoff).
• Check if an emergency stop device is activated.
• Check if the shorting wire between S1 and PC or between S2 and PC is disconnected when not using the safety
stop function.
• An emergency stop device is active when using the safety stop function. Identify the cause of emergency stop,
ensure the safety and restart the system.
• When not using the safety stop function, short across terminals S1 and PC and across S2 and PC with shorting
wire for the inverter to run.
• If "SA" is indicated when wires across S1 and SIC and across S2 and SIC are both conducted while using the
safety stop function (drive enabled), internal failure might be the cause. Check the wiring of terminals S1, S2,
and SIC and contact your sales representative if the wiring has no fault.
FR-E800 Instruction Manual (Functional Safety)