6.2.1 Function of the thread main tension and the thread supplementary tension in relation to the sewingfoot liftingOnly Efka DC 1550 DA 321GThe thread supplementary tension can, at any time, be switched on oroff by actuating the switch key 1 (see chapter 6.17) on the key blockof the machine. To this end, the parameter F-255 must be set on “7".Sewing foot liftingwithing a seamSewing foot liftingafter thread trimmingParametersettingThread maintensionThreadsupplement.tensionThread maintensionThreadsupplement.tensionF-196=0 0 0 0 0F-196=0 1 1 0 0F-196=0 0 0 1 1F-196=0 1 1 1 11 = Thread tension opened mechanically0 = Thread tension closed mechanically· If the thread’ s supplementary tension is opened, this conditionwill be maintained when lifting the sewing foot.· When switching the machine off, the last setting of the thread’ssupplementary tension will be maintained through the mainsconnection.6.2.2 Reparation seam with thread tension always closedOnly Efka DC 1550 DA 321GWhen executing a reparation seam, the thread tension is to stayclosed during the lifting of the sewing foot. Then the setting of theparameter F-196 for the function of the thread main tension and thethread supplementary tension in relation to the sewing foot lifting isnot active.For a quick switching on and off of the reparation seam, a parametersetting first has to be carried out.· Programming the reparation seam with key “A” of the Efkaoperating panel V810/V820: Set the parameter F-293 to 18.· Programming the reparation seam with the key “B” of the Efkaoperating panel V810/V820: Set the parameter F-294 to 18.By actuating the key “A” or “B” on the Efka operating panel V810 orV820, the reparation seam, with the thread tension being alwaysclosed, can be switched on and off quickly.If the reparation seam mode was switched on, at the end of thereparation seam it has to be switched off by actuating the same key ofthe Efka operating panel, in order to activate the parameter F-196again.16