BrutulTM
hit most of the important stuff earlier.
Using grounds as neutrals is common nowadays, in old homes with devices that need neutrals.
Both the grounds and neutrals generally come back to the (main) panel where they're bonded together. So whatever small amount of current is being returned from the switches will return on the grounds. This is now really frowned upon, but you're in an old building so /shrug.
There's concerns, but there's not really any good alternatives for homeowners unless you feel like re-wiring, and most people don't.
If you ever had a neutral splice break somewhere else in the house, that normal operating current might try jumping over to the ground as it tries to return to the transformer. Probably through your switches. But again.../shrug. It'd be a longshot
Using grounds as neutrals is common nowadays, in old homes with devices that need neutrals.
Both the grounds and neutrals generally come back to the (main) panel where they're bonded together. So whatever small amount of current is being returned from the switches will return on the grounds. This is now really frowned upon, but you're in an old building so /shrug.
There's concerns, but there's not really any good alternatives for homeowners unless you feel like re-wiring, and most people don't.
If you ever had a neutral splice break somewhere else in the house, that normal operating current might try jumping over to the ground as it tries to return to the transformer. Probably through your switches. But again.../shrug. It'd be a longshot