Operation
Operating Instructions 878-M PREMIUM - 02.0 - 02/2018 35
Automatic
remaining thread
monitor
For machines with automatic remaining thread monitor:
If the hook thread needs to be replaced, the LED indicator lamps
(2) light up on the machine arm. The left light is for the left-hand
hook, and the right light is for the right-hand hook.
Fig. 16: Remaining thread monitor
Each of the bobbins has a thread supply groove that is embedded
in the bobbin core.
Important: Insert the bobbin in the hook in such a way that the
thread supply groove faces down. Otherwise, the remaining thread
monitor will not work.
(1) - LEDs on the machine arm
①