Alarm Detection - Omron VARISPEED L7 Manual

Alarm Detection

Alarms are Inverter protection functions that indicate unusual conditions without switching off the drive and
operating the fault output contact. The alarm automatically disappears when its cause is eliminated.
During an alarm condition, the Digital Operator/LED Monitor alarm display flashes and an alarm output is
generated at the multi-function outputs (H2-01 to H2-03) if programmed.
When an alarm occurs, take appropriate countermeasures according to the table below.
Display
Forward/Reverse Run Commands
Input Together
EF
Both the forward and the reverse run
External Fault
commands are input simultaneously for
(flashing)
500ms or more. This alarm stops the
motor.
DC Bus Undervoltage
The following conditions occurred
• The DC bus voltage was below the
Undervoltage Detection Level Set-
ting (L2-05).
UV
DC Bus Undervolt • The MC of the inrush current pre-
(flashing)
vention circuit was opened.
• The control power supply voltage
was below the CUV level.
UV Alarm is detected only, when the
drive is in stop condition
DC Bus Overvoltage
The DC bus voltage exceeded the over-
voltage detection level.
OV
DC Bus Overvolt 200 V class: 410 VDC
(flashing)
400 V class: 820 VDC
An OV Alarm is detected only, when
the drive is in stop condition.
Heatsink Overheat
The temperature of the Inverter's cool-
OH
Heatsnk Overtmp ing fin exceeded the temperature pro-
(flashing)
grammed in L8-02.
Enabled when L8-03 = 3.
Overtorque Detection 1
The Inverter's output current (V/f con-
OL3
trol) or the output torque (Vector con-
Car Stuck
trol) exceeded L6-02 for longer than
(flashing)
the time set in L6-03 and L6-01is set to
1 or 2.
Overtorque Detection 1
The Inverter's output current (V/f con-
OL4
trol) or the output torque (Vector con-
Car Stuck
trol) exceeded L6-02 for longer than
(flashing)
the time set in L6-03 and L6-01 is set to
1 or 2.
Table 7.3 Alarm Detection
Meaning
Control sequence is faulty.
For the probable reasons please have a
look at UV1, UV2 and UV3 in table
7.1.
The power supply voltage is too high.
The ambient temperature is too high.
There is a heat source nearby.
The Inverter cooling fan(s) has
stopped.
Motor was overloaded
Motor was overloaded
Probable causes
Check external sequence logic, so
that only one input is received at a
time.
For the corrective actions please
have a look at UV1, UV2 and UV3
in table 7.1
Check the power supply and
decrease the voltage to meet the
Inverter's specifications
Check for dirt build-up on the fans
or heatsink.
Reduce the ambient temperature
around the Inverter
Replace the cooling fan(s).
Ensure the values in L6-02 and L6-
03 are appropriate.
Check application/machine status
to eliminate fault.
Ensure the values in L6-05 and L6-
06 are appropriate.
Check application/machine status
to eliminate fault.
Corrective Actions
7
9
7-