use surge protector from wall pluged into another surge protector(computer grade) to plug in machine and be sure to turn off if not using. The other thing is magnets, do not have anything magnitized near machine this includes pins that have been in a magnitized holder. and if you live near an airport like i do and the planes come low to land from reverse direction if the weather is windy. Turn off your machine !!!!! Plane came over my house and fried the mother board when it contacted the tower. Fortunately BERNINA U.S.A. was able to fix it.