My blog is usually devoted to stereo and home theater subjects but today I'm going to get into another of my passions, home automation. Specifically automated switches and dimmers to make your life easier all around the house.
The brand I have been using exclusively since 2021 is Kasa from TP-Link. They've been very reliable and have replaced almost all the switches in my two bedroom, two bathroom home except for the bathrooms. They have integrated perfectly with both Google and Alexa.
Reading reviews on Amazon I've been left with the impression that a lot of users could use some help in getting professional looking and reliable results, so if that's you, please read on!
Why not bulbs?
Bulbs are fine but they are never a full solution. The advantage of some advanced LED lights is the color changing. The problem is they still rely on you leaving the light switch on, and if you want to go back and forth between using an app or using the wall switch you are out of luck.
This is a major benefit of replacing your wall switch wish a Kasa smart switch. The on/off and dimming capabilities (when present) work seamlessly between the phone app and the wall plate.
Get the right switch
Some Kasa switches have dimmers built in and some do not. Be careful in that the images on Amazon may be misleading. The HS200 switches do not support dimming so they are ideal for fans, switched outlets and outdoor lights.
If you need to dim your bulbs, get the HS220 switches instead. Also, make sure your bulbs support dimming to begin with, not all LED bulbs do.
The last kind of switch is the most complicated to install. What is called the 3-way dimmer switch. It feels like magic until you understand how they work. These switches are used when you need a switch in two locations. This way you can enter a room on one side, turn on the lights, and then turn them off on the other side of the room. Here's a poor drawing of how they are connected:
The key parts to this are that the power is coming from the left, and leaves on the right. Each switch alternates picking between one of two travelers. When both switches pick the same traveler the light goes on. In the diagram above the left switch picked Traveler A, but the right switch picked Traveler B, so the circuit doesn't close and there's no light. If either switch is flipped the light will come on.
You may notice already that a 3-way switch has an extra connection for the traveler which the normal switches don't. Before you install a Kasa 3-way smart switch you need to know where the power is coming from and where the light is connected to. Your Kasa kit will need to have the master switch connected to the breaker side at all times.
Make the connection
If you are uncomfortable with wire nuts or you have very busy boxes I strongly suggest you get a small connector kit from Wago.
They use levers to let you connect a wire at a time instead of nuts. If you are connecting 3 or 4 switches at once you may be better off doing most of the work outside of the box. On your table, wire the ground, neutral and one of the two black wires together using the 5-gang Wago connector. This is 12 wires already hooked up. With a friend to lend a pair of hands you connect all the ground, neutral and hots at once and then each load. That's a lot less wiring.
Make it solid
One of the biggest problems with old homes is that the switches have been replaced so often they've eaten into the drywall, or the drywall was never great to begin with and there's no place for the switch to rest. If you tighten the switch down too much it will no longer be flush with the wall. The solution is simple and cheap. You want to use these little plastic spacers on the mounting screws. Protip: Put the closed side against the switch, the open side up to the screw so they don't fall out when installing.
Keep it Safe
When I moved into my current home the first thing I did was install a whole house surge protector in the main panel. They do get oversold and over-hyped but for devices which you can't put on a surge strip they are your only line of defense. Kasa smart switches have little CPUs in them with a Wifi receiver and are relatively delicate pieces of gear with little in terms of surge protection built in.
