Fyrpoliga

Fyrpoliga is a Swedish term used in electrical engineering to describe equipment or components that have four independent poles or current-carrying conductors. The term is applied to devices such as switches, circuit breakers, relays, contactors, sockets, and connectors where four separate circuits or conductors are intended to be controlled or carried.

In practice, fyrpoliga devices can disconnect four conductors, for example in a four-wire system that may include three live conductors plus neutral, or in configurations where two separate circuits are managed within the same enclosure. In connectors and plugs, a four-pole arrangement provides multiple paths for power and signals, allowing simultaneous connections or isolation of two separate circuits.

Designs of fyrpoliga devices vary: some present four individual single-pole contacts, while others group contacts into two double-pole assemblies within a single housing. The chosen arrangement affects how and when multiple circuits are switched together and has implications for safety interlocks and installation standards.

The term derives from Swedish, combining fyra (four) with pol (pole) and the suffix -ig to form an adjective. In English-language documentation, fyrpoliga is typically translated as four-pole. See also four-pole switch, four-pole connector, and related terminology in electrical engineering.