Safe and Smart: Expert Tips on Using Smart Plugs Safely This Winter - CNET

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Smart plugs can handle a lot for our homes, but they aren’t as durable as your home’s hard-wired outlets.

Smart plugs can be really handy in many ways, but there are still limitations regarding what can be safely used with them.

Many of us will spend more time indoors as cold weather moves in. As we start to find ways to stay cozy with space heaters, heated blankets and more layers, we’ll strain our home’s electrical system more. So, it’s important to be aware of what you're plugging into outlets and where.

In my years of testing portable power stations and other energy monitoring devices, I have learned that anything that heats or cools requires serious power. This means that when you plug in your heaters and blankets to ward off the chill of winter, you may want to think twice about plugging them into a smart plug.

Your home's electrical panel is full of breakers designed to handle specific electrical loads to keep your homes appliances running smoothly and safely.

Smart plugs are great for many things, but even the best smart plug has limitations. In the US, our homes primarily operate on 120 volts, with some appliances requiring 240V. However, the breaker box is the other part of the puzzle regarding our home’s electrical system.

Typically, this is hidden in a closet or a utility room in the basement and will have a gray door. Inside are circuits that help break up your home's electrical usage into smaller pieces so as not to overload your system. Those circuits have breakers with amperage ratings. If that limit is exceeded, the breaker will trip and shut off power to those devices plugged into it to prevent potential fires.

Certified electrician Derek Rhoades of Tradecraft Electric offered insight into our home’s circuits, “Typical receptacles, often called “outlets,” are most commonly rated for 15 and 20 amps. Amps, or “Amperage,” generates heat as it flows through a circuit. The receptacles need to be able to handle the amount of amps that flow through them.”

The outlets that Mr. Rhoades is referring to are the ones hardwired into your home’s walls. Smart plugs generally mirror the same amperage ratings. Most smart plugs are rated for 15A, but some are only 10A.

Aside from amp limitations, smart plugs also have a relatively low operating temperature. As Rhoades points out, “Heating loads, such as space heaters, can be the most damaging to devices and circuits. They not only generate heat as its intended use but also as a byproduct of the large amount of amps that flow through the circuits they operate on.”

Looking at the chart above, you can see that the ratings for smart plugs, hardwired outlets and outdoor plugs are all very similar. However, there are a couple of outliers in the Aeotech Heavy Duty Smart Switch and the Leviton GFCI Outlet. These two offer higher amperage ratings and, in the case of the Aeotech product, can also operate at 220V. But it isn’t a plug; rather, it requires appliances to be hardwired directly into the device.

A Kasa smart plug is a flexible way to schedule your grow light.

Just as you need to know what you’re plugging into extension cords and power strips, the same goes for your smart plugs. Most space heaters, including those on our best space heater list, have a max wattage rating of 1,500. It’s important to be aware how much electricity an appliance will draw and the circuit, breaker, you are connecting it to.

For example, your 1,000W microwave is plugged into a circuit with a 20A breaker and you then plug in your space heater, there is a risk of overloading that circuit if both appliances are running at the same time.

Looking back at the chart from earlier, all those 15A smart plugs match up well with the 15A and even 20A breakers your home uses. However, smart plugs aren’t as durable as the hardwired outlets in your home’s walls. Rhoades states, “A 15 amp device is capable of handling 1800 watts but a device with that much wattage should only be run at that level for short periods, three hours at the most. ”

“If the load you plan on plugging into a 15 amp device exceeds 1500 and will run for a sustained period, it should stick to a max of around 80% of that full load, which comes to 1440 watts.”

I use a two-fan setup with smart plugs and sensors on my Samsung SmartThings smart hub.

Space heaters have benefits, but certain steps should be taken to use them safely. Most smart plugs can handle a space heater. When choosing your heater and where you’re plugging it into, ensure the power needs of the heater, generally 1,500W on high, and the outlet or plug is rated high enough to handle the heater’s electrical draw safely.

When using a smart plug, try to get one with a rating higher than 15A, but those are relatively uncommon. Another way to reduce the risk of problems is to run the heater on a lower setting, requiring less power. However, using two space heaters on the same outlet, even on lower power settings, will overload the circuit, as you’d be doubling the power needs.