electrical
I'm installing some lights in my basement, and will be replacing the single gang box in the hall (currently only for hall light) with a double gang box. The idea is to accommodate the hall light switch and the basement light switch in the same box, but I want to inform anybody who comes after that they will have to turn off two breakers to safely work in the box.
What's the best way to label the box, so people know there are two circuits in the box?
I'm surprised that the switch controls the entire outlet -- generally in that setup (in North America at least), the switch only controls one plug, and the other plug is constant power. In that case of course, the answer is to use a power bar. It may even be worth checking in the plug to see if there is constant power available. You may be able to fix the wiring to work as I've described.
If you can't fix the problem at the plug, then remove the switch, connect the wires together with a wire nut, and then install a duplex faceplate with a blank. The only way I know of to do this is to use the "decora" style blanks, and then either a duplex decora plate, or a combination toggle/decora plate.
Good question, but pause to think: What if all your wiring was in EMT metal conduit? (In which the conduit is the ground). There'd be no choice to bond the grounds, and thus, it is OK.
This question is even easier since you are working out of a sub-panel, which already has its ground bonded to the main panel; that is, one ground rod for the whole house. I have a facility where the 120/240v is served out of two main panels, each with its own supply transformer and its own ground. Circuits from both main panels go into a spiderweb of EMT, and while the neutrals never cross, the EMT certainly does, which means the ground does. What's more, the EMT is attached to an all steel building via girder clamps that are entirely made of metal. It would be impractical to separate the grounds. All this to say: If I am allowed to mix grounds, you certainly are.
Best Answer
Put a divider between the two sides of the box:
Then simply label each side of the gang box as belonging to the appropriate circuit.
Note: Make sure the divider you pick will fit your gang box. I've picked up dividers that don't before.