Abstract: An electronic key may include a partial capacitor comprising a capacitive metal plate in communication with a processor. The capacitive metal plate of the partial capacitor is configured to form a capacitor with a corresponding capacitive metal plate of a lock when brought into proximity with the metal plate of the lock. Data may be transferred from the key to the lock using a capacitor formed by combining the two metal plates, wherein a common ground is established between the metal plate of the key and the metal plate of the lock through a parasitic capacitance present between the key and lock circuitry.

Abstract: An electronic key may include a partial capacitor comprising a capacitive metal plate in communication with a processor. The capacitive metal plate of the partial capacitor is configured to form a capacitor with a corresponding capacitive metal plate of a lock when brought into proximity with the metal plate of the lock. Data may be transferred from the key to the lock using a capacitor formed by combining the two metal plates, wherein a common ground is established between the metal plate of the key and the metal plate of the lock through a parasitic capacitance present between the key and lock circuitry.

Abstract: An electronic key may include a partial capacitor comprising a capacitive metal plate in communication with a processor. The capacitive metal plate of the partial capacitor is configured to form a capacitor with a corresponding capacitive metal plate of a lock when brought into proximity with the metal plate of the lock. Data may be transferred from the key to the lock using a capacitor formed by combining the two metal plates, wherein a common ground is established between the metal plate of the key and the metal plate of the lock through a parasitic capacitance present between the key and lock circuitry.

Abstract: An electronic key may include a partial capacitor comprising a capacitive metal plate in communication with a processor. The capacitive metal plate of the partial capacitor is configured to form a capacitor with a corresponding capacitive metal plate of a lock when brought into proximity with the metal plate of the lock. Data may be transferred from the key to the lock using a capacitor formed by combining the two metal plates, wherein a common ground is established between the metal plate of the key and the metal plate of the lock through a parasitic capacitance present between the key and lock circuitry.

Abstract: In one embodiment, a pharmaceutical cabinet comprises sensors positioned within the frame and door of the cabinet, and the sensors are arranged in a predetermined orientation when the door is closed and a lock is actuated. The sensors are configured to communicate with one another when brought into the predetermined orientation to confirm that the door is closed and the lock is actuated. One or both of the sensors may transmit an identifier to the other sensor, and the communication between the sensors may be encoded. The cabinet also includes a sensor on the lock that indicates if the lock is engaged. The cabinet may generate a record of the times the sensors are moved into or out of communication and the times that the lock is engaged.