VESDA Metal Box HLI - Master-Slave

Secondary monitoring of fire alarms and of other notifications is the recommended VESDA HLI duty, and the interface is also suitable where primary reporting to a fire panel is required. If it is to carry primary reporting, it must first be integrated with the receiving fire panel or primary reporting system and approved or listed with that system, to the fire standards and codes in force.

Wall-mounted and master-slave, VHX-1310 is an Open Protocol HLI in the VESDA range. Communication is host-driven: in response to polling by the host, the HLI generates a single response which is sent back to the host, and in this way, no unsolicited messages are sent from the HLI to the host.

Fault Status reported to the host covers System, Zone, Urgent, Power, Network, Flow and Filter conditions, and fault strings - ASCII strings to describe each fault code - accompany them.

Detector controls available are Reset, Isolate, Silence, Test, Scan and Normalize, the last of these being a master-slave only function, as is configuration of Day and Night alarm thresholds. VESDAnet is a propriety protocol allowing an Xtralis VESDA range of devices to talk on one network, and it is fault tolerant in both directions. Recommended practice keeps a VESDA HLI on secondary monitoring of fire alarms and of the other notifications a VESDAnet produces; primary reporting is suitable as well, though the interface must then be approved or listed with, and integrated into, the panel or reporting system taking that duty, for the relevant fire standards and codes.