SunStar HC Series User Manual page 66

Error Type
Short upper
Upper thread is trimmed
thread after too short and comes
trimming unthreaded
Upper thread is trimmed
too long and thread tail
remains on the embroidery
Thread is not cut Failure of movable and
(at specific
fixed blades
head)
Loose cross tension of the
blades
Movable blade damaged
Incorrect return position of
movable blade
Failure of upper
Short-circuit of fuse (if all
thread holder
heads fail)
solenoid
Poor connection/quality of
solenoid
Bad connection
Poor quality circuit board
Failure to hold
Short strokes of upper
upper thread thread holder
Upper thread holder
overloaded
Cause
check upper thread tension
set LONG or MEDIUM length
of trimmed thread in data set-
up
set MEDIUM or SHORT
length of trimmed thread in
data set-up
if upper thread is held due to
narrow velcro space in upper
thread holder, clean the
velcro
Check screws and crank driver
clamp screws of the movable
blade
Check tension of fixed blade
Change movable blade
Adjust the position of movable
blade
Check/change fuse F1, F2, F3
in joint board
Check/change solenoid &
connection
Check connection
Change thread detecting plate
in sub controller
Adjust stroke
Adjust the workload
Inspection & Repair Reference
The default is MEDIUM
Check fuse spec