What can you plug into a smart plug? Most devices that draw well under the plug’s rated load, in a place the plug is rated for, with motors, heaters and big appliances as the exceptions. Lamps, humidifiers and coffee makers work on all three plugs here. Fans have motors, so check them first. Space heaters, fridges and air conditioners belong on a wall outlet instead.
| Product | Maximum load | TP-Link’s 80% figure | Motor rating | Where it works |
|---|---|---|---|---|
| GHome Wi-Fi Smart Plug | 10A, 1,200W | None given by GHome | Not published | Indoors, away from humid places |
| Kasa EP10P2 Smart Plug Ultra Mini | 15A, 1,800W per plug | 1,440W | 1/6 HP | Indoors, 32°F to 104°F |
| Kasa EP40A Outdoor Smart Plug | 15A, 1,875W across both outlets | 1,500W | 1/2 HP | Outdoors, IP64, -4°F to 122°F |
Yes on all three plugs: lamps, humidifiers and coffee makers
The Kasa EP10 user guide sets a ceiling for each kind of load it supports. The everyday ones sit far below even the lowest-rated plug here, the GHome Wi-Fi Smart Plug at 1,200W:
- Desk lamp up to 235.2W, humidifier up to 260W, LCD screen up to 270W.
- Coffee maker up to 800W, still inside every limit in the table below.
A smart plug only switches the power on or off, from an app, by voice or on a schedule. It can’t press buttons. So leave the appliance’s own hardware button “On”, as TP-Link advises, and it runs the moment the plug sends power, which matters for a coffee maker you want hot when you wake up.
How to work out a smart plug’s limit
Each plug’s watt rating is its amps times the voltage. So 10A at 120V gives the GHome’s 1,200W, 15A at 120V gives the EP10’s 1,800W, and the EP40A’s 125V rating turns its 15A into 1,875W.
Then leave headroom. TP-Link says it’s “not recommended to run the plug at full load for extended periods,” and for long runs it wants no more than 80% of the plug’s maximum on it. On the EP10, that’s 1,440W. On the EP40A, it’s 1,500W. GHome gives no such figure, so treat its 1,200W as a ceiling, never a target.
Your device’s watts are on its label. You can check how they line up against the plug limits in our comparison table at the top of this guide.
Check first: motors, irons and toasters
Watts alone don’t settle it for a motor. TP-Link builds its plugs mainly for resistive loads, and it gives heaters, kettles and irons as examples. But TP-Link warns that some inductive loads “can draw a significantly higher inrush (peak) current at startup,” and that surge may damage a plug even when the device’s rating looks safe. Fans, vacuum cleaners and water pumps are on its list.
That’s why the motor rating matters. The EP10 takes motors up to 1/6 HP and the EP40A up to 1/2 HP. GHome publishes none. The EP10 guide lists a tower fan at up to 50W as a supported load, but a fan’s motor still needs the horsepower check. Kasa even names swimming pool pumps as an EP40A use, so compare the pump’s horsepower with 1/2 HP first.
Irons and toasters are a watts question instead. The guide lists a toaster at up to 850W, yet TP-Link still puts toasters on its use-with-caution list. Set the guide’s 1,500W iron against each plug and you get three answers: over the GHome’s 1,200W, over the EP10’s 1,440W figure and right at the EP40A’s 1,500W. Irons are on that caution list too.
No: keep heaters, fridges and air conditioners off a smart plug
TP-Link says its plugs aren’t suitable for high-power motor loads, and it names air conditioners, refrigerators and washing machines. The US Fire Administration wants “refrigerators, stoves, washers and dryers” plugged directly into a wall outlet.
Space heaters split the maker and the safety agencies. The EP10 guide lists a heater at up to 1,500W among its supported loads, while TP-Link puts space heaters on its caution list. The Consumer Product Safety Commission is plainer: plug electric space heaters “directly into a wall outlet.” A smart plug sits between the heater and the wall, so it breaks that rule. The US Fire Administration’s heating guidance also says to turn space heaters off when you leave the room or go to bed. A schedule could switch one on while you’re out. Keep heaters on the wall outlet.
EV chargers stay off the Kasa pair too. TP-Link says “EV charging is not supported,” since a car’s charging current may run past what the plug is rated for.
Indoors, outdoors or a cold garage
Only one smart plug here goes outside, the EP40A. GHome’s manual says “Do not use this product in a humid environment or outdoors.” The EP10 is indoor only too, and its guide allows “unheated/unoccupied spaces such as garages,” but its 32°F floor rules out a garage that freezes.
The EP40A is rated IP64 against dust and splashing water. Kasa’s requirement is blunt: it “Must Plug Into Gfci Receptacles If Used Outdoor Or In Wet Locations.” Snap the included weather-resistant cover over any socket you aren’t using.
So the place picks the plug. Get the GHome Wi-Fi Smart Plug for lamps and other low-draw devices indoors. GHome also sells a 15A plug under a similar name, so check for “10A” on yours. Skip it for anything over 1,200W.
Choose the Kasa EP10P2 Smart Plug Ultra Mini for higher-draw devices indoors, such as a coffee maker. It’s a two-pack of UL-certified 15A plugs. Buying for someone else? See our smart home gifts.
Go for the Kasa EP40A Outdoor Smart Plug for string lights and garden gear. Its two outlets switch separately but share 15A in total. Skip it if two devices together pass 15A.
Wi-Fi, apps and voice control
None of the three needs a hub. Each joins 2.4GHz Wi-Fi directly, and the Kasa pair sets up in the Kasa app. GHome’s page and manual name both the GHome and Gosund apps, so follow the instructions in the box. All three work with Alexa and Google Assistant. The EP40A adds Apple Home, which isn’t on the EP10’s or GHome’s list, and TP-Link’s HomeKit card says a home hub such as a HomePod or Apple TV helps with remote control there. Our Zigbee vs WiFi vs Matter guide shows which other kinds of plug need a hub.
Schedules, standby power and power cuts
All three can switch at set times or at sunrise and sunset. The Kasa pair adds an Away Mode, which switches devices on and off at random times while you’re away so the house looks lived in. That works for a lamp, not a heater.
Schedules also cut standby power. That’s the electricity a device uses while it’s off or in standby, and the Department of Energy puts it at 5 to 10 percent of home energy use. When the plug cuts power to a TV overnight, the TV’s standby draw stops with it.
Power cuts are the catch. GHome’s manual says its plug should “resume its state in the app,” and that “timers are still set as is.” TP-Link’s smart devices must get back online to resync their clocks after an outage, and until then “the schedule, timer, and away mode feature will not continue to work.” Kasa doesn’t say whether a plug comes back on or off.
Other questions people ask
Can a power strip go on a smart plug?
A power strip isn’t recommended on Kasa plugs, TP-Link says. If you use one anyway, the combined rated power of everything on the strip can’t exceed the plug’s maximum, so add up the watts first. GHome’s manual doesn’t mention power strips, and its only related warning is “Do not insert your device to another one.”
What shouldn’t go on a smart plug because it needs constant power?
Devices that need uninterrupted power aren’t recommended on Kasa plugs, TP-Link says. A smart plug can cut the power on a schedule or after a mistaken tap in the app. So keep anything that must stay on, such as a freezer or medical equipment, plugged straight into the wall outlet.
Where shouldn’t you put a smart plug?
TP-Link says to keep its Kasa plugs out of direct sunlight, high temperatures and enclosed spaces. So a plug shut in a cabinet or baking in a sunny window is in the wrong spot. GHome’s manual adds “Do not place this product near heating devices, such as microwave ovens, stoves, or radiators.”