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Failure Investigation for Electronic Parts Main motor rotation abnormal
• Main motor rotational variance
or
• Does not reach maximum speed
or
• Speed cannot be adjusted
Replace SS-VR F2 PCB assy.
When the speed control lever is
moved with the power ON, does the
voltage between pins 2 & 1 of CN1
on the operation U22 PCB assy. vary
0.7 – 4.3 V DC?
N
Replace NP F2 PCB assy.
Replace main NF3D PCB assy.
When the upper shaft pulley is slowly
turned by hand, does the voltage
between pins 2 & 1, pins 4 &1 and
pins 5 & 1 on the main NF3D PCB
assy. vary 0 – 5 V DC?
N
Y
Y
Summary of Contents for BLMY
Page 1: ......
Page 2: ......
Page 3: ......
Page 19: ...1 8 ...
Page 21: ...2 2 Main parts location diagram Main unit ...
Page 30: ...2 11 Disassembly Electrical parts and motors location diagram Main unit ...
Page 37: ...2 18 Thread tension mechanism location diagram Main unit ...
Page 43: ...2 24 Bobbin winder mechanism location diagram Main unit ...
Page 49: ...2 30 Needle bar presser mechanism Upper shaft mechanism location diagram Main unit ...
Page 53: ...2 34 Needle presser module breakout diagram 78 Modules ...
Page 66: ...2 47 Disassembly Feed and bobbin module breakout diagram Modules ...
Page 75: ...2 56 Thread cutter module breakout diagram Modules ...
Page 79: ...2 60 ...
Page 81: ...3 2 Needle bar presser mechanism upper shaft mechanism location diagram Main unit ...
Page 90: ...3 11 Assembly Bobbin winder mechanism location diagram Main unit ...
Page 94: ...3 15 Assembly Thread tension mechanism location diagram Main unit ...
Page 102: ...3 23 Assembly Electrical parts and motors location diagram Main unit ...
Page 109: ...3 30 Main parts location diagram Main unit ...
Page 120: ...3 41 Assembly Needle presser module breakout diagram 78 Modules ...
Page 139: ...3 60 Feed module breakout diagram Modules ...
Page 155: ...3 76 Thread cutter module breakout diagram Modules ...
Page 161: ...3 82 ...
Page 191: ...4 30 ...
Page 226: ......