Duerkopp Adler 550-867 Service Instructions Manual page 93

"Teach-In"
During the monitored seam sections the values of the occurring thread
tensions will be compared to a preset tolerance range. If the thread
tensions deviate from the tolerance range more often than desired the
seam will be defined as bad seam .
Adjusting the thread tension to the required tolerance range
The value of the needle thread tension is influenced by several factors
like sewing speed, material, sewing thread, seam section etc. With the
function "Thread tension" the upper and lower limits for the needle
thread tension can be set.
Step 1:
Setting the thread tension at the operating point and at the limits.
–
Enter the corresponding values for the tearing seam into the field
for "lower limit", "upper limit" and "target value".
(Manufacturer's data)
–
Enter the maximum speed.
–
Enter stitch length and lift stroke.
–
Press "Set Fa". The thread tension value is adopted.
–
Check the thread tension using a thread scale.
–
Adjust the value for "Current lifting magnet" correspondingly.
Lower value = Lower thread tension
Higher value = Higher thread tension
–
Also check "lower limit" and "upper limit" (Fu, Fo).
–
Press the button "next step".
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