Electrical switch

An electrical switch for extinguishing an electric arc, the electrical switch comprising:

• a stationary contact assembly having a stationary contact;
• a moving contact assembly having a moving contact, the contact assembly being configured to move between a closed position in which the moving contact is in contact with the stationary contact and an open position in which the moving contact is not in contact with the stationary contact;
• and
• an arc extinguishing chamber adjacent the stationary contact assembly and the moving contact assembly and extending from the stationary contact to a first location of the moving contact when the moving contact is in the open position, the arc extinguishing chamber comprising:
• a first group of arc extinguishing grids spaced a first distance from one another;
• and
• a second group of arc extinguishing grids spaced a second distance from one another that is less than the first distance,
• wherein the first group of arc extinguishing grids is between the moving contact assembly and the second group of arc extinguishing grids such that the electric arc generated by the stationary contact and the moving contact is cut by the first group of arc extinguishing grids before being cut again by the second group of extinguishing grids.

A method of extinguishing an electric arc in an electrical switch, the method comprising:

• generating an electric arc by moving a moving contact of a moving contact assembly from a closed position in which the moving contact is in contact with a stationary contact of a stationary contact assembly to an open position in which the moving contact is not in contact with the stationary contact;
• allowing the electrical arc to move radially outward within an arc extinguishing chamber adjacent the stationary contact assembly and the moving contact assembly with the arc extinguishing chamber extending from the stationary contact to a first location of the moving contact when in the open position;
• cutting the electric arc into a first set of sub-arcs by a first group of arc extinguishing grids spaced a first distance from one another as the electrical arc continues to move radially outward within the arc extinguishing chamber;
• and
• cutting the first set of sub-arcs into a second set of sub-arcs by a second group of arc extinguishing grids spaced a second distance from one another as the first set of sub-arcs continue to move radially outward within the arc extinguishing chamber, the first group of arc extinguishing grids being closer to the stationary contact than the second group of arc extinguishing grids.