Omron M1 Series User Manual page 757

Alarm
Alarm
sub-
code
code
(0Cn)
(0H1)
M1 Series Standard Type User's Manual (I669)
Name Description
(6) Internal braking
transistor short detec-
tion has operated
(7) Malfunction be-
cause of noise
Instantaneous
overcurrent
(1) The ambient tem-
perature exceeds the
inverter specification
range
(2) The airflow path is
blocked
(3) Reduced fan airflow
because of the cooling
fan service life or of
damage
Cooling fin
overheating
(4) High load
9 Troubleshooting
Check point and remedy reference
Check that the braking resistor connection
terminal (P+, DB) is not shorted.
Check if the connected braking resistor re-
sistance value is very low.
→ Connect the appropriate braking resis-
tor.
Check methods for measures against noise
(grounding conditions, control/main circuit
wiring and installation).
→ Implement measures against noise. For
details, refer to 2-3-4 Wiring for Main
Circuit Terminals on page 2-15.
→ Enable the retry function (H04).
→ Connect a surge absorber to coils, sol-
enoids, etc. in magnetic contactors that
are the cause of noise.
Measure the ambient temperature.
→ Reduce the ambient temperature such
as by improving the air flow to the pan-
el.
Check that there is sufficient installation
space.
→ Re-install at a site where sufficient in-
stallation space can be ensured.
Check for fin clogging.
→ Clean.
Check Cumulative Run Time of Cooling Fan
(H43).
→ Replace the cooling fan.
Visually check that the cooling fan is operat-
ing correctly.
→ Replace the cooling fan.
Measure the output current.
→ Set 28:OHF (Cooling fin overheat warn-
ing) to Output Terminal [DO1] Function
Selection (E20), Output Terminal [DO2]
Function Selection (E21) or Output Ter-
minal [ROA, ROB] Function Selection
(E27) whose load is to be reduced. Al-
ternatively, reduce the load before an
overload occurs using the Overload
early warning 2 Level (OL2) (E34).
→ Reduce the Carrier Frequency (F26).
→ Enable Overload Prevention Control
(H70)
9
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