Four transformer-isolated barriers are available to suit most applications for interfacing fire detectors onto conventional and addressable systems as well as driving IS sounders / beacons.

With all types, the infallible component is the toroidal transformer designed into each product. Each barrier has been tested and certified so that over voltage on the primary (safe) side of the transformer cannot release energy across the winding to the secondary (hazardous) winding of the transformer.

This is a significant difference in design from more conventional zener barriers, in which all fault current is shunted via the zener diodes to earth.

With transformer-isolated barriers, no earth is required, making installation simpler, particularly on fire detection systems in which only one area of a building is classified as hazardous.

A matching range of enclosures is also available to suit the requirements of each barrier interface. The first enclosure, ENC-03, can accommodate up to six conventional JBA-1EX barriers.

The ENC-04 enclosure contains two 35mm DIN rails to accommodate both transformer barriers on one rail and loop translators on the other, resulting in the correct creepage and clearance distances being maintained between hazardous and non hazardous terminals.

The use of transformer isolated barriers combined with sounders means that installers may wire both detectors and sounders/beacons with no requirement for an intrinsically safe earth, making for a more simplified and cost-effective approach to hazardous areas.