Abstract: Aspects of the present disclosure provide an intentional leak from a rear volume of an ear cup to the atmosphere. The leak is created via a vent in the driver plate acoustic assembly. The vent reduces an acoustic load the ear cup cover creates on a rear cavity of an electroacoustic transducer contained within the driver plate acoustic assembly of a headset. Additionally, the vent is hidden on an assembled ear cup of a headset. Due to the placement of the vent, ear cup cover may have a smooth, seamless surface.

Abstract: Aspects of the present disclosure provide an intentional leak from a rear volume of an ear cup to the atmosphere. The leak is created via a vent in the driver plate acoustic assembly. The vent reduces an acoustic load the ear cup cover creates on a rear cavity of an electroacoustic transducer contained within the driver plate acoustic assembly of a headset. Additionally, the vent is hidden on an assembled ear cup of a headset. Due to the placement of the vent, ear cup cover may have a smooth, seamless surface.

Abstract: A monitoring system for a NAC (Notification Appliance Circuit) is provided. The monitoring system includes a system controller, and a NAC comprised of one or more notification appliances that may be in a series. The NAC and its appliances may be operatively coupled to the system controller. The system controller is operable to determine whether a notification appliance has sufficient voltage at a low voltage operation. The system controller may control the voltage to the NAC in order to provide power to simulate operation of the NAC using battery power. A voltage may be measured during the simulation (such as at one end of the NAC). The measured voltage may be compared with a predetermined minimum operating voltage for the notification appliance. Based on the comparison, it may be determined whether the one or more appliances on the NAC may operate properly when the NAC is operated using battery power.

Abstract: A monitoring system for a NAC (Notification Appliance Circuit) is provided. The monitoring system includes a system controller, and a NAC comprised of one or more notification appliances that may be in a series. The NAC and its appliances may be operatively coupled to the system controller. The system controller is operable to determine whether a notification appliance has sufficient voltage at a low voltage operation. The system controller may control the voltage to the NAC in order to provide power to simulate operation of the NAC using battery power. A voltage may be measured during the simulation (such as at one end of the NAC). The measured voltage may be compared with a predetermined minimum operating voltage for the notification appliance. Based on the comparison, it may be determined whether the one or more appliances on the NAC may operate properly when the NAC is operated using battery power.

Abstract: An emergency lighting unit includes a lamp, a backup battery, controller, and a network interface. The controller connects the backup battery to the lamp upon detection of an emergency condition and loss of main power. The network interface interfaces with and receives commands from a fire alarm control panel via a fire alarm network. Each emergency lighting unit may have a unique identifier with respect to the fire alarm network.

Abstract: An emergency lighting unit includes a lamp, a backup battery, controller, and a network interface. The controller connects the backup battery to the lamp upon detection of an emergency condition and loss of main power. The network interface interfaces with and receives commands from a fire alarm control panel via a fire alarm network. Each emergency lighting unit may have a unique identifier with respect to the fire alarm network.

Abstract: An emergency lighting unit includes a lamp, a backup battery, and controller and a network interface. The controller connects the backup battery to the lamp upon detection of an emergency condition and loss of main power. The network interface interfaces with and receives commands via a fire alarm network. Each emergency lighting unit has a unique identifier with respect to the fire alarm network.