Pfaff 1571 Instruction Manual page 49

Set-up
 If necessary, Enter the code number, see chapter 9.10 Entering / changing the code
number.
 Switch on bobbin thread monitoring via stitch counting (value "1").
 Call up parameter "2210"
 Enter the number of stitches that can be sewn with a bobbin, for example 12000
or
 Click on the button, eg enter 12000
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