GE General Electric Sewing Machine AF-300 User Manual
-72-
Check part
Check item
How to inspect
Evaluation criteria
Resistor
1)Unpleasant smell and crazing
of the insulation by
overheating
2)No open circuit?
of the insulation by
overheating
2)No open circuit?
1)Olfactory and
visual inspection
2)Visual inspection
or use a multimeter
by removing a
connection on one
side.
visual inspection
2)Visual inspection
or use a multimeter
by removing a
connection on one
side.
1)Not abnormal.
2)Less than about ±10% of
the indicated
resistance value
2)Less than about ±10% of
the indicated
resistance value
Trans-
former and
reactor
former and
reactor
Abnormal buzzing or unpleasant
smell?
smell?
Aural, olfactory, and
visual inspection
visual inspection
Not abnormal.
Main circuit
Magnetic
contactor
and relay
contactor
and relay
1)Rattling when operating?
2)Roughness of contact?
2)Roughness of contact?
1)Aural
2)Visual inspection
2)Visual inspection
1), 2) Not abnormal.
Control circuit
Control PC
board and
connector
board and
connector
1)Loose screws or connectors?
2)Unpleasant smell or
discoloration?
3)Cracks, damage, deformation, or
excessive rust?
4)Electrolyte leakage or a
deformed mark on the
capacitor?
2)Unpleasant smell or
discoloration?
3)Cracks, damage, deformation, or
excessive rust?
4)Electrolyte leakage or a
deformed mark on the
capacitor?
1)Tighten more.
2)Olfactory and
visual inspection
3),4)Visual
inspection
2)Olfactory and
visual inspection
3),4)Visual
inspection
1), 2), 3), 4)
Not abnormal.
Not abnormal.
Cooling
fan
(2 HP or
more)
fan
(2 HP or
more)
1)Abnormal sound or vibration?
2)Loose of bolts?
3)Discoloration by
overheating?
2)Loose of bolts?
3)Discoloration by
overheating?
1)Aural and visual in-
spection. Turn with
hand. (Make sure power
is off)
2)Tighten more
3)Visual inspection
spection. Turn with
hand. (Make sure power
is off)
2)Tighten more
3)Visual inspection
1)The fan must rotate
smoothly.
2), 3)Not abnormal
smoothly.
2), 3)Not abnormal
Cooling system
Ventilation
way
way
Clogging-up or foreign substance on
heat sink or intake/exhaust ports?
heat sink or intake/exhaust ports?
Visual inspection
Not abnormal
(Note) Use a capacitance measuring instrument available on the market which is easy to use.
(Remark) If the equipment is stained, wipe it with a cleaning cloth, which is chemically neutral.
Vacuum-clean the dust.