Instruction manual

EFKA AB221A/AB321A + AB222A/AB322A (BA)

The end backtack/end stitch condensing in a seam with stitch counting starts by heelback at the end of counting, or, from

the light barrier seam at the end of the light barrier compensating stitches. The stitch regulator is immediately enabled from

machine standstill. After lowering the sewing foot, the switch-on point of the stitch regulator is delayed by the time t3 (start

delay after switching off the sewing foot lift signal). The first leading edge of position 1 counts as 0 stitch whenever the

function is not started in position 1. If backtack synchronization (parameter 298) is not switched on, the stitch regulator is

synchronized to position 1. End backtack as well as end stitch condensing are performed automatically at speed n4. They

cannot be interrupted. From full machine run, end backtack / end stitch condensing will be switched in only after having

reached the speed n4 and synchronization to position 2.

9.5.1 Speed n4 at the Seam End

Function with or without control panel Parameter

End backtack/end stitch condensing speed (n4) 113

End backtack/end stitch condensing speed can be interrupted by pedal in pos. 0 (neutral) (n2E) 163

Start and end backtack or stitch condensing can be interrupted by pedal in pos. 0 (neutral) (StP) 164

On/Off

When programming 3-digit or 4-digit parameter values on the control, the 2-digit or 3-digit values displayed must be

multiplied by 10.

9.5.2 Stitch Counting for End Backtack/End Stitch Condensing

Function with or without control panel Parameter

Number of stitches forward or without stitch regulator (c3) 002

Number of stitches backward or with stitch regulator (c4) 003

Double end backtack repetition (wer) 091

Backtack repetition On/Off (Fwr) 092

The end backtack/end stitch condensing stitches with or without stitch regulator can be programmed and varied using the

above parameters directly on the control or on a connected V810/V820 control panel.

For fast operator information (HIT) when using the V820 control panel, the value of the function switched on using key 4

can be displayed for approx. 3 seconds. During this time, the value can be varied directly by pressing the + or - key.

9.5.3 Stitch Correction and Last Stitch Backward

Function with or without control panel Parameter

Last stitch backward On/Off (FAr) 136

Stitch correction time (c9) 151

The backtack solenoid can be delayed in the double end backtack by selecting a stitch correction time (t9) using parameter

151.

For some sewing procedures it is desirable that the backtack solenoid in the single end backtack is disabled only after

trimming. This function can be selected using parameter 136.

136 = 0 trimming stitch backward Off

136 = 1 trimming stitch backward On in the single end backtack

136 = 2 trimming stitch or positioning stitch always backward at the seam end

9.5.4 Double End Backtack/End Stitch Condensing

The backward section and/or end stitch condensing will be executed for a number of stitches that can be set. Then the stitch

regulator will be disabled and the forward section and/or normal stitch condensing stitches will be executed. The number of

stitches for the two sections can be set separately.

After stitch counting (parameter 003) the trimming function will be initiated. During the entire operation the sewing speed

is reduced to speed n4, with the exception of the last stitch, which will be performed at positioning speed n1.

In the case of slow backtack mechanisms it is possible to delay disabling of the stitch regulator in the single and double end

backtack by the time t9 (end backtack stitch correction).