VESDA PC Link HLI Open Protocol Master/Slave

VESDA HLIs are recommended for secondary monitoring of fire alarms and other notifications from VESDAnet network. They are also suitable for primary reporting to the fire panel or other primary reporting systems. When used for primary reporting VESDA HLIs need to be integrated and approved or listed with the relevant fire panel or the primary reporting system for the relevant fire standards and codes.

VHX-0310 is the Open Protocol HLI (Master-Slave), a VESDA high level interface which links a VESDAnet to PC software monitoring tools, Building Management Systems (BMSs) and Fire Alarm Control Panels (FACPs). In the master-slave model, the host supervises the communications link between itself and the HLI (slave) by regularly polling the HLI to determine whether there has been a change in the status of a detector on VESDAnet.

Depending on the polling strategy adopted, the Master/Slave Open Protocol HLI is able to report any and all fire alarms within a few seconds of a detector going into alarm, and exact performance is dependent on the polling strategy adopted.

Electrically the unit takes 24 VDC and 70 mA (Quiescent), consuming 1.68 W (Quiescent), and it weighs 0.4 kg (0.9 lbs). Up to 40 detectors are supported and modem support is not available. Alarm status (Alert, Action, Fire1 & Fire2) and detector status (Isolated, Normalizing, AutoLearn, Scanning) both cross the link to the host. Secondary monitoring - fire alarms, plus other notifications raised across a VESDAnet - is the duty a VESDA HLI is recommended for; primary reporting to a fire panel or other primary reporting system is also suitable, but only once the unit has been integrated and approved or listed with that panel or system for the relevant fire standards and codes.