Brother HE-800B Service Manual page 9

7-12-5. Adjusting the cutting depth of the upper
thread scissors ............................................ 99
7-12-6. Adjusting the installation height of the
upper thread scissors ................................ 100
7-12-7. Adjusting the upper thread scissors
gradual opening timing .............................. 101
7-12-8. Adjusting the upper thread scissors
opening timing ........................................... 102
7-12-9. Adjusting the overlapping amount of the
upper thread scissors and the work clamp 103
7-13.
Adjusting the lower thread trimming................. 104
7-13-1. Adjusting the lower thread trimmer fixed
knife engagement amount ......................... 104
7-13-2. Adjusting the lower thread retaining
amount ...................................................... 104
7-13-3. Adjusting the lower thread clamp opening
timing ........................................................ 105
7-13-4. Adjusting the lower thread clamp opening
amount ...................................................... 106
7-14.
Adjusting the bobbin presser ........................... 106
7-15.
Adjusting the thread breakage detector ........... 107
7-16.
Adjusting the thread tension at the tack
tension control ................................................. 108
7-17.
Adjusting the thread tension at the zigzag
tension control ................................................. 108
7-18.
Adjusting the upper thread feeding amount ..... 109
7-19.
Adjusting the rotary hook lubrication ................ 109
7-20.
Adjusting the upper shaft motor reference
position ............................................................ 110
7-21.
Standard settings for treadle depression
stroke ............................................................... 111
8. INSTALLING THE 3-PEDAL FOOT
SWITCH (OPTION) .............................
9. ELECTRIC MECHANISM ...................
9-1.
Precautions at the time of adjustment ................ 113
9-2.
Components inside and outside the control box
and in the operation panel ................................. 114
9-3.
Fuse explanation ................................................ 115
9-4.
Connectors......................................................... 116
9-4-1. Connector positions ..................................... 116
9-4-2. Contact failure ............................................. 118
9-5.
Troubleshooting ................................................. 123
9-5-1. Troubleshooting flowchart ........................... 123
9-5-2. Problem solution and measures .................. 127
10. TABLE OF ERROR CODES .............
11. TROUBLESHOOTING ......................
11-1.
Upper thread breakage .................................... 148
11-2.
Skipped stitches............................................... 149
11-3.
Uneven seams (1)......At the sewing start ....... 151
11-4.
Uneven seams (2)......Lower thread is lifted
up at the sewing start ....................................... 152
11-5.
Uneven seams (3)......Seam lifts up at the
sewing start...................................................... 152
11-6.
Uneven seams (4)......Uneven sewing pitch at
the sewing start ............................................... 153
11-7.
Uneven seams (5)......Poor rounding of seam 153
11-8.
Uneven seams (6)......Around rear tack or
front tack .......................................................... 153
11-9.
Uneven seams (7)......Loose thread end at
end backtack ................................................... 153
11-10.
Uneven seams (8)......Thread sticking out at
end backtack ................................................. 154
11-11.
Uneven seams (9)......Sticking in needle
plate .............................................................. 154
11-12.
Uneven seams (10)......All stitches ............... 155
11-13.
Upper thread run out ..................................... 156
11-14.
Unraveling of thread trimmed by upper
thread trimmer assembly .............................. 158
11-15.
Upper thread miss-trimming .......................... 159
11-16.
Needle strikes upper thread trimmer ............. 160
11-17.
Needle breakage ........................................... 161
11-18.
Imperfect cutter function (imperfect material
cutting) .......................................................... 162
11-19.
Cutter does not return ................................... 162
11-20.
Cutter and upper thread trimmer touch ......... 163
11-21.
Seam is cut ................................................... 163
11-22.
Upper thread miss-winding............................ 164
11-23.
Work clamp is not raised (1)......Error does
not occur. ...................................................... 164
11-24.
Work clamp is not raised (2)......Error occurs.
...................................................................... 165
11-25.
Lower thread is not trimmed (pulls when
material is removed) ..................................... 166
11-26.
Feed mechanism does not move and error
occurs. .......................................................... 166
11-27.
Needle does not zigzag or noise occurs
112
when needle zigzags .................................... 167
113
11-28.
Sewing machine stops during sewing ........... 167
11-29.
Upper shaft does not rotate as far as the
needle up stop position ................................. 167
11-30.
Operation panel display freezes and
operation is not possible ............................... 167
142
148
HE-800B