The terms dry and wetted have nothing to do with the physical construction of the contacts.
A dry contact is a contact that receives power from a source. Examples include:
Thermostats, Pushbuttons, Doorbell buttons, relay contacts, door switches, and even standard light switches.
A wetted contact is a contact that provides power to a load. Examples include:
Time clock switches, Commercial float/pressure switches, and most low voltage solid state controls.
