Baby Lock BL7800, Руководство по обслуживанию

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4.
Main motor does
not run.
5)
Is the presser foot lever lowered, or does the
presser foot switch operate correctly?
Resistance at both ends of switch:
When switch is pressed .......... 1
Ω
or less
When switch is released .........
∞
6)
Others
5)
Replace the presser foot SW
assembly.
6)
Replace the main PC board
assembly or power unit
assembly.
5.
Operation of main
motor is not stable,
maximum speed
operation is not
possible, or speed
cannot be adjusted.
1)
When turning on power and moving the
speed slide, does voltage between pins 3-2 of
the speed VR connector change between DC
0 to 5 V?
2)
When operating the machine at a slow speed,
do voltages between pins 2-1, 4-1, 5-1, 6-1 of
connector CN3 of the NP PC board each
alternate between DC 0 to 5 V?
3)
Others
1)
Replace the VR PC board
assembly.
2)
Replace the NP PC board
assembly.
3)
Replace the main PC board.
6.
Correct patterns are
not created.
1)
If the power is turned off and the needle bar is
moved horizontally by hand, does it move
easily?
2)
Are the resistances between the connectors
for the zigzag, feed, and side feed pulse
motors normal?
Zigzag (CN1).................. 1-3, 2-4
→
8-10
Ω
Feed (CN2).................. 1-3, 2-4
→
8-10
Ω
3)
When operating the machine at a slow speed,
do voltages between pins 2-1, 4-1, 5-1, 6-1 of
connector CN3 of the NP PC board each
alternate between DC 0 to 5 V?
4)
Others
1)
Adjust the installation position so
that it moves easily.
2)
Replace the malfunctioning
pulse motor or the lead wire
assembly.
3)
Replace the NP PC board
assembly.
4)
Replace the main PC board
assembly.
7.
Buttonholes are not
stitched correctly.
1)
Is the presser foot correct?
2)
Is the resistance between pins 4-5 of the BH
switch connector (CN5) normal?
When buttonhole lever is lowered .... 1
Ω
or less
When buttonhole lever is raised ......................
∞
3)
When the buttonhole lever is lowered and in
the conditions below, is the resistance
between pins 1-2 and 2-3 of the BH switch
connector (CN5) normal?
Between 1-2 Between 2-3
Buttonhole lever is
pulled forward.................. 1
Ω
or less
∞
Buttonhole lever is
pushed back ....................
∞
1
Ω
or less
4) Others
1)
Check
2)
Adjust or replace the BH switch
assembly.
3)
Adjust or replace the BH switch
assembly (see page 30).
4)
Replace the main PC board
assembly.
8.
Manual operation of
feed and zigzag is
not possible.
1)
The feed and zigzag manual keys turn off and
on normally?
2)
Does the voltage alternate between DC 0 to 5
V at both ends of the main PC board
condensers C4 and C9 when the power is
turned on and the feed manual VR and zigzag
manual VR are slid?
3)
Are the resistances normal between the pins
of the feed and zigzag pulse motors listed
below?
Feed (CN2).................. 1-3, 2-4
→
8-10
Ω
Zigzag (CN1).................. 1-3, 2-4
→
8-10
Ω
4) Others
1)
Replace the operation board
assembly.
2)
Replace the operation board
assembly.
3)
Replace the feed or zigzag pulse
motor, or the lead wire
assembly.
4)
Others