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Firefighters Override Mode

Firefighter’s Override Mode

In any enclosed space, fire and smoke control is a major life-safety concern. Firefighter’s override mode allows the HVAC system to control, contain and extract fire and smoke using air flow and air pressure. When operating in override, the drive ignores most operating conditions that would otherwise cause it to fault and shut down. It continues to operate as long as possible regardless of line, load or environmental conditions.
Firefighter’s override can run the drive at any speed in forward or reverse. It can be activated either by a normally open or normally closed contact from the fire panel or through the building automation system. The drive can be set to switch automatically to a constant speed bypass if operation through the drive becomes impossible due to failure of the drive’s power circuitry. The bypass will then run the motor at full speed from the power line until firefighter’s override is deactivated.

Firefighter’s override is standard in all VLT HVAC Drives, and can be configured through user-accessible parameters. It can be set up and activated at any time. As fire codes or the needs of the facility change, the adaptable VLT HVAC Drive is ready.