Interlockok

Interlockok are devices or arrangements that prevent a system from entering an unsafe state or from performing an unsafe action until certain conditions are met. Interlocks are used to enforce safe sequencing, to ensure access controls, or to guarantee that machines or processes do not operate under dangerous combinations of states. They are found in a wide range of industries, from manufacturing plants to consumer products and transportation.

Interlockok systems can be categorized by method and function. Mechanical interlocks rely on a physical constraint, such as a pin, latch, or cam, to block a subsequent action. Electrical interlocks use circuits, relays, or contactors to prevent conflicting operations—often by wiring to sensors, guards, or start controls. Safety interlocks are designed to meet functional safety requirements; they frequently include redundancy, diagnostic capabilities, and fail-safe behavior. In software-controlled environments, interlocks are realized as state checks and conditional logic that prevent progression to the next step unless prerequisites are satisfied. In railway signaling, interlockings coordinate routing and block occupancy to prevent two trains from taking conflicting routes.

Common applications include guarding on machinery (doors and gates must be closed before a press will start), process automation (certain conditions must be true before a reactor feed is permitted), and secure access systems (doors that remain locked until authentication succeeds).

Design considerations emphasize reliability, compatibility with other safety measures, and compliance with international standards such as ISO 14119, IEC 61508, and ISO 13849-1.

Overall, interlocks are a broad family of devices and logics intended to reduce risk by preventing unsafe actions through controlled sequencing and access.