Avpåsignal

Avpåsignal is a term used in Swedish and Norwegian control engineering to describe a signal that commands a device or system to turn on (på) or off (av). It denotes a binary control line that governs power or a control function, and is typically part of start/stop sequences, safety interlocks, or other state-changing operations.

In practice, an avpåsignal is a digital or quasi-digital input or output that enables or disables equipment. It can be active-high or active-low depending on the wiring and equipment design. Common sources include pushbuttons, switches, sensors, or PLC outputs, and the signal may be transmitted locally or over a communication network, often as part of an automation or safety system.

Implementation considerations for avpåsignal include reliability and debouncing of mechanical inputs, correct electrical isolation, and compatibility with existing control logic or fieldbus systems. In safety-critical applications, the design typically favours fail-safe behavior, so loss of the avpåsignal should bring the machine or process to a safe state. Some installations use redundant channels or interlocks to reduce the risk of unintended state changes.

Examples of use include a start avpåsignal that enables a motor drive in a conveyor system, a stop avpåsignal that disables operation, or a safety interlock where closing a guard generates an avpåsignal to permit operation while opening the guard terminates it. Avpåsignal thus plays a central role in coordinating power, control, and safety in industrial automation.