Replacing a regular light switch
The simplest way to use SwitchMote is to replace a single light switch that is hard wired to a single load (ex. a light). Make sure to disconnect the breaker of the circuit of your light before proceeding with this step. Here are illustrated steps for replacing one of the switches in a 2 gang electrical box containing 2 regular switches. A new cover plate was required to fit the old switch along with the new SwitchMote. Many cover configurations are readily available at HomeDepot or online. Otherwise you can keep your old cover plate if you are replacing a rectangular light switch.
For this particular install a short neutral wire had to be added to the nut where the white wires were merged (needed for the “N” neutral connector on the SM PSU). The other 2 black wires were trimmed to about 3/16″ exposed wire and connected to the “S1” and “S2” terminals on the SM PSU. It does not matter which way the black wires are connected to these S1 and S2 terminals. That’s one of the nice features of SwitchMote, you don’t have to worry which is the source (from the panel) and which is the load (light bulb). For SwitchMote2x10A you must connect the black (hot in) wire to the “H” terminal (you might need to determine which is the hot coming from the source/panel first). Make sure there are no exposed wires left unconnected or protected by wire nuts. The earth GND wires are bare copper and should be pushed back in the box to avoid touching the electronics of the SwitchMote. The back cover is meant for this specific purpose and the metal screws that hold it are not connected to anything on the SwitchMote PCBs. Adding some electrical tape around the nylon spacers adds even more protection from anything that might reach inside the SwitchMote. With the 3 wires tightly screwed in the terminals of SM you can turn on the breaker for a quick test without touching the wiring. The LEDs should turn ON and normal operation should begin just as if it were connected through the FTDI.
Use the screws from the old switch make to mount SwitchMote to the wall electrical box. If this is a brand new install then just use some common M6 screws of at least 1 inch length. Screw through the oval routed holes into the 2 end holes where the old switch was screwed, making sure the SwitchMote Shield PCB will sit flush with the wall and approximately parallel with the box or other light switches around it. Be gentle, do not force the screws into the PCB as it may snap or cause copper traces to break.
For the cover plate gently thread the cover plate screws in the 2 outlier plated holes on the SwitchMote Shield. Then you are ready to mount the cover plate. Take care while fitting the cover plate over the switch. Sometimes plastic electrical boxes are poorly fitted into the wall by the builders, and it might be less than easy to fit a light switch into its own cover. Same is true here for SwitchMote. It is more difficult when you have another traditional switch in the same box along with SwitchMote, as shown in the following photos. If it doesn’t want to fit easily don’t force the SwitchMote to fit, you will likely have to lessen the screws, and the oval holes allow adjusting the SwitchMote position. Use common sense, SwitchMote is a sensitive electronic device and force will not do it any good.
Please note: the below photos show the simple single-relay SwitchMote – for this any of the S1 and S2 terminals can act as input while the other is the switched output. In SwitchMote2x10A this is not the same – there is a dedicated HOT input (“H”) and two (“S1”, “S2”) switched outputs.
Replacing 3-way light switches
You can certainly replace two light switches arranged in a 3-way combination. Here’s a typical 3-way switched circuit arrangement:
This is a more advanced circuit, so you must fully understand how 3-way switching works, don’t attempt this otherwise. First make sure the Neutral wire is available at both boxes (white wire). You then have to identify which of the two boxes has the Hot (black wire) that leads to the load(s), this is the load-box. You will install the load-bearing SwitchMote in the load-box. The other box is just a switch-box and you will install a SwitchMote that only needs power (N from white wire and either of the S terminals from black wire on regular SwitchMote and N(white)+H(black) on SwitchMote2x10A). Even though the switch-box SwitchMote has a relay and it will turn on, there is no load on it, this is OK (you may choose to not solder the relay on that SwitchMote). Once both are installed only the load-box SwitchMote can control the load/light. You can now SYNC the two such that both turn the light on/off. After this is complete, the switch-box SwitchMote will communicate with the load-box SwitchMote wirelessly to control the load and synchronize the red/green status LEDs on both ends. Note that ground (copper) and red wires that are now left unused should be separately isolated with wire nuts and left in the box for any future changes.