Dürkopp Adler 550-867 Operating Instruction page 263

Setup
Operating Instructions 550-867 - 00.0 - 11/2016
7. Open the Setup display ( p. 139).
8. Tap the Sewing motor button.
 The display switches to:
Fig. 216: Performing a test run
9. Perform a test run, first at low speed and then at continually
increasing speeds.
10. Check that the seams conform to the desired requirements.
Information
Change the needle thread tensions if the requirements are not
satisfied ( p. 43). If necessary, also check the settings listed in
the  Service Instructions and correct them as required.
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