Mitsubishi Electric 800 Series Instruction Manual page 645

Causes and corrective actions
Abbreviation
Name
Description
Check point
Corrective action
Abbreviation
Name
Description
Corrective action
Abbreviation
Name
Description
Check point
Corrective action
Abbreviation
Name
Description
Check point
Corrective action
644
PROTECTIVE FUNCTIONS
E.SAF
Safety circuit fault
• Appears when internal circuits are malfunctioning.
• Appears when one of the lines between S1 and PC, or between S2 and PC is opened.
• Check if the shorting wire across the terminals S1 and PC or the terminals S2 and PC is disconnected.
• Short across the terminals S1 and PC and the terminals S2 and PC with shortening wires.
E.PBT
E.13
Internal circuit fault
The inverter trips when an internal circuit fault occurs.
Please contact your sales representative.
E.OS
Overspeed occurrence
The inverter trips when the motor speed exceeds the Pr.374 Overspeed detection level under encoder
feedback control, Real sensorless vector control, vector control, and PM sensorless vector control. This
protective function is not available in the initial status.
• Check that the Pr.374 setting is correct.
• Check that the number of encoder pulses does not differ from the actual number of Pr.369 (Pr.851) Number
of encoder pulses (under encoder feedback control or vector control).
• Check that the motor temperature is not increased under Real sensorless vector control. (The motor
constant may vary due to increase in the motor temperature.)
• Set the Pr.374 correctly.
• Set the Pr.369 (Pr.851) correctly (under encoder feedback control or vector control).
• Enable the online auto tuning at startup (set Pr.95 (Pr.574) = "1") (under Real sensorless vector control).
(Refer to page 444.)
To perform the online auto tuning at startup for a lift, use of the Start-time tuning start external input (X28)
signal is recommended.
E.OSD
Vector Vector Vector
Speed deviation excess detection
• The inverter trips if the motor speed is increased or decreased under the influence of the load etc. during
vector control with Pr.285 Speed deviation excess detection frequency set and cannot be controlled in
accordance with the speed command value.
• If the motor is accelerated against the stop command accidentally, the deceleration check function (Pr.690)
is activated to stop the inverter output.
• Check that the values of Pr.285 and Pr.853 Speed deviation time are correct.
• Check for sudden load change.
• Check that the number of encoder pulses does not differ from the actual number of Pr.369 (Pr.851) Number
of encoder pulses.
• Set Pr.285 and Pr.853 correctly.
• Keep the load stable.
• Set Pr.369 (Pr.851) correctly.
FR-LU08 Safety circuit fault
FR-PU07 E.SAF
FR-LU08 PBT fault
FR-PU07 Fault
FR-LU08
Fault 13
FR-PU07
FR-LU08 Overspeed occurrence
FR-PU07 E.OS
FR-LU08 Spd deviation fault
FR-PU07 E.OSd