USA is open to anything I think
I work in a manufacturing plant that produces building wire (electrical wire for commercial and residential construction). We have many different PLC's in the plant from previous regimes of engineers and maintenance personnel responsible for equipment specification. Since I started equipment specifications for capital projects in 1999, I have standardized on Allen-Bradley products (SLC, PLC, MicroLogix, and now starting to use ControlLogix in some applications). We do still on occasion receive used or surplus equipment that has other brands in it (or antiquated discrete relay logic - ugh!). If we can get away with it, we will gut the cabinet and start over with ALB. We are just more comfortable and have local support for this platform, but I am sure that if you polled the entire US, you would get a plethora of different answers! Then again, I am in the armpit of Arizona, not exactly an industrial automation hotbed! lolis