Abstract: An electrical power disconnect switch is disclosed which provides for mechanical or manual tripping operation, as well as electrical or automatic tripping operation. The switch includes a latch pin, a switch body including a handle member, and fixed and movable contacts. A biasing spring biases the contacts to an open position. The latch pin has an electrical trip coil surrounding it to cause the latch pin to releasably hold the switch body in a position such that the contacts are closed. The latch pin is retracted from the switch body by manual depression of a handle member, causing the contacts to open. Alternatively, the latch pin is released from the switch body to open the contacts when current ceases to flow through the electrical trip coil. The current flowing through the electrical trip coil is supplied from a protection circuit. In an automobile application, the protection circuit may be, for example, a hood open or crash detection circuit.