18.
Automatic speed adaptation
18.1 General
78
The "Speedomat" function allows a speed limitation dependent on the
set stroke height (at setting wheel 1) up to 21 steps. The current stroke
height value is indicated to the sewing drive control by the position of
the potentiometer (10k Ohm with 60° angle of rotation), which is
connected to the lifting shaft in the sewing machine arm. The maximum
angle of rotation of the lifting shaft amounts to 48° and adjusts the
potentiometer from 9k Ohm (= 4,5V at bushing A.3 = nmax) to 1k Ohm
(= 0,5V at bushing A.3 = nmin).
See wiring diagram 9890 768003 B for connection of potentiometer.
Setting eccentric
[Position]
min.
A
B
C
D
E
F
max.
Sewing foot
Max. number
stroke
of stitches
[mm]
3.500 / 3.200
1,5
2,4
3,3
4,2
5,1
6,0
1
-1
[min
]
2000