Alarm Detection - YASKAWA CIMR-G7U Technical Manual

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Alarm Detection

Alarms are detected as a type of Drive protection function that do not operate the fault contact output. The sys-
tem will automatically returned to its original status once the cause of the alarm has been removed.
The Digital Operator display flashes and the alarm is output from the multi-function outputs (H2-01 to H2-
03).
When an alarm occurs, take appropriate countermeasures according to the table below.
Display Meaning
Forward/Reverse Run Commands
EF
Input Together
(blinking)
Both the forward and reverse run com-
External
mands have been ON for more than
Fault
0.5 s.
Main Circuit Undervoltage
The following conditions occurred
when there was no Run signal.
UV
• The main circuit DC voltage was
(blinking)
below the Undervoltage Detection
DC Bus
Level Setting (L2-05).
Under-
• The surge current limiting contactor
volt
opened.
• The control power supply voltage
when below the CUV level.
Main Circuit Overvoltage
OV
The main circuit DC voltage exceeded
(blinking)
the overvoltage detection level.
DC Bus
200-240 V class: Approx. 400 V
Overvolt
380-380 V class: Approx. 800 V
OH
(blinking)
Cooling Fin Overheating
Heat-
The temperature of the Drive's cooling
sink
fins exceeded the setting in L8-02.
Over-
temp
Drive Overheating Pre-alarm
OH2
An OH2 alarm signal (Drive overheat-
(blinking)
ing alarm signal) was input from a
Over
multi-function input terminal (S3 to
Heat 2
S12).
OH3
Motor overheating
(blinking)
E was set for H3-09 and the motor
Motor
temperature thermistor input exceeded
Over-
the alarm detection level.
heat 1
Table 7.2 Alarm Displays and Processing
Probable causes
-
See causes for UV1, UV2, and UV3
faults in the previous table.
The power supply voltage is too high.
The ambient temperature is too high.
There is a heat source nearby.
The Drive cooling fan has stopped.
-
The motor has overheated.
Protective and Diagnostic Functions
Corrective Actions
Check the sequence of the forward and
reverse run commands.
Since the rotational direction is
unknown, the motor will be deceler-
ated to a stop when this minor fault
occurs.
See corrective actions for UV1, UV2,
and UV3 faults in the previous table.
Decrease the voltage so it's within
specifications.
Install a cooling unit.
Remove the heat source
Replace the cooling fan. (Contact your
Yaskawa representative.)
Clear the multi-function input termi-
nal's overheating alarm input.
Check the size of the load and the
length of the acceleration, decelera-
tion, and cycle times.
Check the V/f characteristics.
Check the motor temperature input on
terminals A1 and A2.
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