How are electromechanical locks powered?

• A. Line-powered
• B. Self-powered and battery-powered
• C. Solar-powered
• D. Hydraulic-actuated

Answer: (B)

Electromechanical locks move their bolt or solenoid using electrical energy, so they must have a power source. The usual ways are internal batteries that keep the lock powered without being wired to building power, or energy that’s generated or captured during operation (self-powered) so the lock can function without a constant external power supply. Some installations do connect to building power (line-powered), but that adds wiring and is less common for standalone devices. Solar power exists in some outdoor or low-power cases, but it’s not the standard approach. Hydraulic-actuated systems aren’t typical for these locks, since hydraulics add fluid plumbing and pressure rather than the electrical actuation used in electromechanical models. So the most accurate description is that these locks are powered by internal batteries or by energy harvested during use.