Causes and Countermeasures for Main Switch Failure
|Failure in electrical characteristics||Contact failure||Foreign matter is attached to the contacts.||Use sealed switches to prevent the entry of foreign matter.|
|Films forming on contact surfaces||Use switches with gold contacts, which have wiping effects.|
|Insufficient contact force between the contacts caused by an incorrect stroke.||Set a suitable stroke.|
|Malfunction||Contact chattering caused by vibration or shock.||Use switches with large contact forces between the contacts (i.e., with a high operating force (OF)).|
|Welding||The switching capacity of the contacts was exceeded.||Use a high-capacity switch.
Insert a contact protection circuit.
|Insulation deterioration||The contacts are spattering due to arcing.||Use a high-capacity switch.|
|Failure in mechanical characteristics||Failure to operate||The mechanism is damaged due to an incorrect stroke, overload, or shock.||Set a suitable stroke and operate the switch at a suitable operating speed and with a suitable load.|
|Foreign matter has entered the switch and is caught in the mechanism or contacts.||Use sealed switches to prevent the entry of foreign matter.|
|External damage||An overload was placed on the actuator because of the dog or cam shape or because an unsuitable operating method was used.||Change the design of the dog or cam and use suitable operating methods.|