What Is a Brownout and What Should You Do During One?

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Brownouts have the potential to cause annoying occurrences (such as erratic appliance behavior), but can also cause serious damage to valuable electronics.

If you know what a power surge is, a brownout is essentially the opposite. Instead of the voltage surging, the voltage sags, sometimes referred to as a voltage slump. However unlike power surges brownouts are sometimes caused on purpose by utility companies. Putting a power grid into a brownout for some can prevent overloads, stopping a potential blackout. Common and annoying but usually harmless traits of brownouts are flickering lights, the rapid switching on and off of appliances and interruptions to computing and the internet. However when it comes to valuable electronics, the irregular voltage can damage or destroy them. Therefore it is important to know what to do during a brownout, so that the risk of electronic damage is minimized.

Lights are more sensitive to brownouts, as any voltage changes alter their brightness. Appliances such as TVs smooth out the smaller voltage changes because they contain a lot of capacitors, which store electricity that can be used during times of low voltage to 'level it out'. This does not mean however, that complex appliances won't get damaged as much as lights in a brownout. It just means that the early signs of a brownout can be seen through lighting. In fact, lighting does not get damaged at all by brownouts. So when the lights start flickering badly the first thing you should do is unplug computers, TVs, printers, routers and cell phones or other devices that are charging.

During a brownout you should reduce your power consumption as much as possible. Why? Because brownouts are caused by a lack of electricity, so if everyone temporarily reduces the amount of power they're using the brownout will be over sooner. You don't need to switch off everything in your house, just heavy power suckers such as TVs, heaters, washing machines, dryers and dishwashers. Remember that you can resume all these appliances once the brownout is over. The length of brownouts can vary quite a lot. Some last only a few minutes, while others continue to toggle on and off for hours.