Maeda MC405C-3 - Electric Motor

Section 5 – TROUBLESHOOTING Mini-Crawler Crane M A E D A
5-94 1/2019 MC405C-3
Electric Motor
Abnormal Phenomenon
Major Cause(s)
Actions
The motor remains off
despite the switch being
turned to the "START"
position.
• Improper wiring and power supply
error
• The Inverter unit breakers: OFF
• A break in stator winding
• Check wiring, see "ELECTRIC
MOTOR OPERATION" on page 4-
134.
• Turn ON the breakers.
(• Inspection, repair, replacement)
(• Inspection, repair, replacement)
The motor comes to a stop
during use.
• Inverter unit error
(Red lamp: ON)
• Failure in the Inverter unit
• Failure in the power unit
• Check the power supply source
(voltage and phase interruption).
(• Inspection, repair, replacement)
(• Inspection, repair, replacement)
The power output of the
motor reaches zero or
undergoes gradual
decrease.
• Phase interruption in the power
source of power supply equipment
• Slack in motor wiring
• Check the power source of power
supply equipment (voltage and
phase interruption).
• Inspect connection with the motor
Terminal block.
(• Inspection, repair, replacement)
The cabtyre cable rises in
temperature.
• Considerable voltage drop
• Ensure that the power supply
voltage of power supply equipment
is at a specified value.
• Replace the cabtyre cable with one
adhering to specifications.
An abnormal noise and
vibration are present in the
power unit during operation.
• A break in motor winding
• Looseness in the motor and pump
fixing bolt
• Looseness in the coupling fixing
bolt
• Impurities on the coupling
• Clogging in the hydraulic oil tank
strainer and element
• Inspect the motor Terminal block.
(• Inspection, repair, replacement)
• Perform inspection, repair, and
cleaning. See "ELECTRIC
MOTOR OPERATION" on page 4-
134.
(• Replacement)
• Clean and replace the strainer and
element according to periodic
inspection.
The power unit rises in
temperature during
operation.
• High ambient temperature
• Ill-ventilated
• Considerable voltage drop
• Overload
• High number of starts
• Use the power unit in environment
compliant with specifications.
• Perform inspection and cleaning,
See "ELECTRIC MOTOR
OPERATION" on page 4-134.
• Replace the cabtyre cable with one
adhering to specifications.
• Reduce loads.
• Reduce the number of starts.
The leak detector of the
Inverter unit main breaker is
tripped.
• High humidity
• Presence of water droplets
• Ill-grounded
• A break in stator winding
• Use the leak detector in
environment compliant with
specifications.
• Attach the cover properly.
• Adhere to ground standards.
(• Inspection, repair, replacement)
The trouble lamp (red) of
the Inverter unit comes on.
• Failure in the Inverter unit
(• Inspection, repair, replacement)