Next time that it happens check in the ladder G4.3 (W-Search) and see what conditions bring this coil on. This is the "Single Block" address. When this turns on it puts you into single block mode.
Next time that it happens check in the ladder G4.3 (W-Search) and see what conditions bring this coil on. This is the "Single Block" address. When this turns on it puts you into single block mode.