I've been collecting rolling stock and various components for several years. I have my train table built to fit the corresponding track plan which I have attached. I have mostly MTH Proto 3 engines and have purchased one Z4000 along with one TIU and AIU. My plan is to have four main lines running so I plan on purchasing another Z4000 and I know I need another AIU since I have more than ten switches. (If anyone has either one for sale that would be helpful). I want to set up the system so it offers me the opportunity to switch any line over to conventional use via a toggle switch in case the little ones want to run a "beater" engine conventionally I won't care.
My question is...Do i need another TIU to do what I want to do? I plan Star wiring with each track independently powered. I hope I have given you enough information. Keep in mind i'm new at this,
so try to keep your answers in a format that a novice will understand. Many thanks for your assistance.