Smart Plugs: What They Can and Cannot Automate
Smart plugs are the cheapest entry into home automation and the easiest to misjudge. The device does exactly one thing: it switches mains power to whatever is plugged into it. Everything follows from that.
The rule that predicts everything
Does the appliance turn on by itself when power returns?
If yes, a smart plug controls it. If it needs a button press or waits in standby, the plug can only cut power — it cannot press the button.
Works well
- Lamps with a physical switch left in the on position
- Fans with a mechanical switch (not remote-controlled ones)
- Water pumps and motors within the plug's rating
- Geysers and immersion heaters, if within rating — scheduling one to heat before you wake is among the most genuinely useful uses in India
- Chargers and Christmas lights — anything that simply starts working when powered
- Older air conditioners with a mechanical dial, though see the caution below
Does not work
- Televisions. Power returns and the TV sits in standby. You have not turned it on.
- Most modern air conditioners. They power up in standby awaiting the remote. For these, an infrared blaster is the right device, not a plug.
- Anything with a soft-touch power button — the button state resets.
- Devices that must shut down cleanly, such as computers. Cutting power is not switching off.
Where it is a bad idea
Refrigerators. A compressor restarted against residual head pressure draws a very large current and can be damaged. Never put a fridge on a scheduled or automated plug.
Anything that must not restart unattended — irons, heaters, cooking appliances. A schedule that fires when nobody is home is a fire risk, not a convenience.
Medical equipment, or anything someone depends on.
Ratings matter more than features
This is the specification people skip. Indian plugs are commonly sold in two ratings:
| Rating | Roughly | Suits |
|---|---|---|
| 10A | Up to ~2300W | Lamps, fans, chargers, TVs, routers |
| 16A | Up to ~3500W | Geysers, air conditioners, motors |
A geyser on a 10A plug is a genuine hazard. Check the appliance's wattage on its rating plate and buy the plug to match, with margin. Look for BIS certification; this is a mains-connected device that will run unattended.
Note also that 16A plugs are physically larger and may not fit a crowded extension board, and that many smart plugs are too bulky to allow a second plug beside them in a twin socket.
Ecosystem and what happens offline
Most smart plugs are Wi-Fi and 2.4GHz only — they will not see a 5GHz-only network, which trips up a lot of first-time setups. Check compatibility with whatever assistant you use before buying.
More importantly, ask what happens when the internet is down. Many plugs route commands through the manufacturer's servers, so an outage means the app stops working. Two things mitigate this:
- A physical button on the plug itself — non-negotiable in my view, so you are never locked out of your own appliance
- Schedules stored on the device rather than in the cloud, so a timer keeps running without a connection
Energy monitoring
Many plugs report power consumption. Accuracy is approximate and they are not billing-grade, but as a way to find out what a particular appliance actually costs to run, they are genuinely informative — often surprising.