Filament sensor broke off

Looks like there was a knot in the filament and the pulling forces broke off the arm with two of the three "ultimate filament sensor" s on my modified Ultimaker II extended.
It houses the load cell to meassure filament pulling force and the encoder to meassure filament odimetry.
Both where not enabled at that time and thus didn't pause the print as soon as forces exceeded the allowed range.