Protective And Diagnostic Functions; Fault Detection - Omron VARISPEED E7 User Manual

Protective and Diagnostic Functions

This section describes the alarm functions of the Inverter. The alarm functions include fault detection, alarm
detection, operation error detection, and autotuning error detection.

Fault Detection

When the Inverter detects a fault, the fault contact output operates, and the Inverter output is switched OFF
causing the motor to coast to stop. (The stopping method can be selected for some faults.) A fault code is dis-
played on the Digital Operator.
When a fault has occurred, refer to the following table to identify the fault and to correct the causes.
Use one of the following methods to reset the fault before restarting the Inverter:
Set a multi-function contact input (H1-01 to H1-05) to 14 (Fault Reset) and turn ON the error reset signal.
•
Press the RESET key on the Digital Operator.
•
Turn the main circuit power supply OFF and then ON again.
•
Display
7
2
7-
Meaning
Overcurrent
The Inverter output current
exceeded the overcurrent detection
level.
Ground Fault
The ground fault current at the
Inverter output exceeded approxi-
mately 50% of the Inverter rated
output current.
Fuse Blown
The fuse in the main circuit is
blown.
Main Circuit Overvoltage
The main circuit DC voltage
exceeded the overvoltage detection
level.
200 V class: Approx. 410 V
400 V class: Approx. 820 V
Probable Causes
• A short-circuit or ground fault
occurred at the Inverter output. (A
short or ground fault can be caused
by motor burn damage, worn insu-
lation, or a damaged cable.)
• The load is too large or the accelera-
tion time is too short.
• A special-purpose motor or motor
with a capacity that is too large for
the Inverter is used.
• A magnetic switch was switched at
the Inverter output while running.
A ground fault occurred at the Inverter
output. (A ground fault can be caused
by motor burn damage, worn insula-
tion, or a damaged cable.)
One of the output IGBT's has failed
because of a short-circuit or ground
fault at the Inverter output.
The deceleration time is too short and
the regenerative energy from the
motor is too large.
The power supply voltage is too high.
Corrective Actions
Reset the fault after correcting its
cause.
Reset the fault after correcting its
cause.
• Check the motor and cables for
short circuits or insulation fail-
ures.
• Replace the Inverter after cor-
recting the cause.
Increase the deceleration time or
connect a braking option.
Decrease the voltage so that it is
within the inverters specifications.