Electronic locks use components such as magnets, solenoids and motors instead of mechanical tumblers. Some of these devices use keypads, others have magnetic or optical card readers, and the most secure versions use both. Electronic locks will sometimes also include mechanical tumblers as a backup, in which case a regular key can be used to bypass the other security methods. Most of these devices are battery powered, so they need to be serviced from time to time in order to continue operating. Electronic locks are typically installed on doors, but they can also be used to secure safes and in other similar applications.
There are two main types of electronic locks. One common version is the standalone unit, which can be installed anywhere a traditional lock is found. Since these units are self-contained, they can typically be installed without requiring any modifications to a door. Doorknobs with integrated electronic locks can be installed into single-bored doors, while electronic deadbolts are usually intended for use with double-bored doors.
Standalone electronic locks are typically battery powered, which means they need to be serviced regularly. Most of these units are designed to provide some type of warning when the battery level is low, such as a beeping sound or flashing light. Many standalone units also include mechanical tumblers though, in which case a key can be used to bypass the electronic lock altogether. This can be useful if the battery goes dead without warning.
The other main kind of electronic lock can be used in conjunction with access control systems. These systems are found in facilities where access to an entire building, or even rooms within a structure, must be tightly controlled and monitored. The electronic lock will typically be wired into the access control system and may also receive external power as well. Whenever the lock is actuated, it can inform the system that someone has passed through. In some cases, the access control system can also disable an electronic lock to refuse access to an area.
There are also several different ways for an electronic lock to be operated. One common method of operation is a keypad, which is a set of buttons that are labeled with either numbers or letters. When the buttons are pressed in a correct sequence, the solenoid or motor within the device can release the lock. The other main way of controlling electronic locks is with a key card. Biometrics and other methods are also commonly used, especially in conjunction with access control systems.