The 1S40 is an optical sensor that is used to transmit the flash of light emitted during the incidence of an arcing fault back to an arc fault monitor such that detection of arcing faults can be achieved in as little as a few ms.

The 1S40 linear sensor may be applied to protect large volumes where multiple point sensors would otherwise be required. A separate 1S40 linear sensor is required for each segregated protection zone.

The linear sensors kits provide both cladded and bare fibres. The bare fibres are located within the detection zone and cladded fibres allow routing of the linear sensor back to the relay.

Bare fibre and cladded fibres are joined through the use of optical fibre couplers. An optical fibre duplex connector is utilised for connection to the arc flash relay.