Mitsubishi Electric FR-A820-00046 (0.4K), Instruction Manual

Page: 1073 / 1218

Protective functions Causes and corrective actions
FR-A800 6 - 33
Operation panel
indication
E.SAF FR-LU-08 Safety circuit fault
Name Safety circuit fault
Description
앫
The inverter trips when a safety circuit fault occurs.
앫
The inverter trips if the either of the wire between S1 and SIC or S2 and SIC becomes non-
conductive while using the safety stop function.
앫
When not using the safety stop function, the inverter trips when the shorting wire between
terminals S1 and PC or across S2 and PC is disconnected.
Check point
앫
Check that the safety relay module or the connection has no fault when using the safety
stop function.
앫
Check if the shorting wire between S1 and PC or between S2 and PC is disconnected when
not using the safety stop function.
Corrective action
앫
When using the safety stop function, check that wiring of terminal S1, S2 and SIC is correct
and the safety stop input signal source such as a safety relay module is operating properly.
Refer to the Safety Stop Function Instruction Manual for causes and countermeasures.
(Please contact your sales representative for the manual.)
앫
When not using the safety stop function, short across terminals S1 and PC and across S2 and
PC with shorting wires. (Refer to page 2-63.)
Operation panel
indication
E.PBT
FR-LU-08
PBT fault
E.13 Intrnl circuit fault
Name Internal circuit fault
Description The inverter trips when an internal circuit fault occurs.
Corrective action Please contact your sales representative.
Operation panel
indication
E.OS FR-LU-08
Overspeed
occurrence
Name Overspeed occurrence
Description
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 point
앫
Check that the Pr. 374 setting is correct.
앫
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).
Corrective action
앫
Set the Pr. 374 correctly.
앫
Set the Pr 369 (851) correctly (under encoder feedback control or vector control).
Operation panel
indication
E.OSD FR-LU-08 Spd deviation fault
Name Speed deviation excess detection
Description
앫
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.
앫
If the motor is accelerated against the stop command accidentally, the deceleration check
function (Pr. 690) is activated to stop the inverter output.
Check point
앫
Check that the values of Pr. 285 and Pr. 853 "Speed deviation time" are correct.
앫
Check for sudden load change.
앫
Check that the number of encoder pulses does not differ from the actual number of Pr. 369
(851) "Number of encoder pulses".
Corrective action
앫
Set Pr. 285 and Pr. 853 correctly.
앫
Keep the load stable.
앫
Set Pr. 369 (851) correctly.
Vector Vector Vector