Emergency Lighting: Understanding Brownout Features in Exit & Emergency Lights.

Summer is here, and so is the sweltering heat. As a result, during extended periods of excessively hot weather, your customers' air conditioners will most likely be running nonstop. And they use a lot of energy. So much so that utility companies have to manage the supply vs. demand during high-use periods. When energy usage is near or above the utility’s maximum production capacity, it may intentionally reduce the flow of electricity to your customers' businesses. This reduction in electricity is called a brownout.

When a brownout is announced, a managed reduction in electricity still flows to your customers' businesses. As a result, they may notice dimming lights or even interruptions in the ac. This reduction in line voltage can have serious implications for computers, appliances, and motorized equipment too. Consequently, it is not advisable that any of these items be operated during a brownout.

During a brownout, your customers may also notice that their Emergency Lights and battery-backed-up Exit Signs may illuminate, even though their normal lighting is still operational. This is because virtually all self-powered Emergency Lighting fixtures have a "brownout feature". Emergency Lighting fixtures that offer brownout protection automatically switch to emergency mode when the supplied voltage drops below approximately 80 percent nominal of 120, 220, or 277 VAC. The main reason manufacturers include this feature is because standard fluorescent lighting will fail if the line current drops below 80 percent. In that event, Emergency Lighting with the brownout feature will help provide illumination. It's just one more way that Emergency Lighting Systems help keep your customers safe.