Omkopplare

Omkopplare is a term used in Swedish to describe a changeover switch or selector switch in electrical engineering. It refers to a mechanical device that redirects a circuit from one path to another, enabling selection between different signals, power sources, or operating modes. The concept is common in control panels, consumer electronics, and industrial equipment.

Omkopplare are classified by the number of poles and throws. Common configurations include SPDT (single-pole double-throw), DPDT (double-pole double-throw), and multi-pole variants. In each configuration, a common contact can connect in one position to a specific output and, in another position, to a different output. Actuation styles vary and include rotary, toggle, slide, and push-button designs. Some switches are maintained (latching) and stay in the chosen position, while others are momentary and return to a default state when released.

Construction and operation typically involve a housing with terminals and an external actuator. The device provides a defined electrical path in each position, with electrical ratings for voltage and current that determine suitable applications. Selection depends on factors such as load, isolation, insulation, mechanical life, and environmental conditions. Sealed or rugged variants exist for harsher environments.

Applications for omkopplare span a wide range, including selecting among input sources in audio and video equipment, setting operating modes on appliances, routing signals in laboratory instruments, and controlling machines within industrial control panels. They are chosen for simplicity, robustness, and immediate, user-directed control of circuit connections.

Standards and safety considerations address electrical isolation, creepage and clearance, contact reliability, and environmental sealing. Proper material choice for contacts and coatings helps minimize wear and arcing over repeated cycling.