| 摘要 |
A method and apparatus for preventing a GFCI device from being miswired is provided where the GFCI device is enabled to enter a latched state only after the GFCI device is correctly wired to a power supply. An exemplary GFCI device includes a latch assembly provided with a rigid electrically conducting bar connected thereto such that when a user presses a reset button provided on the GFCI device, the latch assembly is moved toward a pair of contacts provided as part of a reset circuit to initiate a reset operation. When the electrically conducting bar on the latch assembly connects the pair of contacts, the reset circuit is closed and an actuator is activated to place the GFCI device in the latched, reset, condition. If the GFCI device is correctly wired, the closed reset circuit will cause a firing member to move from a first position to a second position enabling the latch assembly to enter the latched state. The exemplary latch assembly is connected to a resilient biasing member that biases the latch assembly and the shorting bar away from contacting the pair of contacts except when urged against the force of the resilient biasing member by a user of the GFCI device. Further, because the GFCI device is delivered in the tripped, unlatched state, and cannot be latched, or placed in the reset condition, until it is properly wired, the miswiring prevention functionality is immune to vibrations or shock prior to the device being installed. According to further embodiments a automatic self-test circuit is provided for periodically testing the fault detection ability of the device without human intervention. |
