Location: Carleton, MI - Interlocking Tower

The interlocking tower at Carleton controlled the crossing of the north-south Pere Marquette (later C&O/CSX) and the east-west Detroit, Toledo & Ironton (later CN/I&O).

Image Info: Top, a photo of the interlocking tower in Carleton, looking northeast from the diamond. 2nd image, the model board in the tower at Carleton [Charlie Whipp], 3rd photo, a track diagram of Carleton in the 1980's. 4th image, a drawing of the Carleton interlocking in 1955. 5th image, the conductor picks up orders from the ironman at Carleton.  [Both, Charles Geletzke Jr.]

Notes

Time Line

1912. The railroad commission approves a map of the crossing of the DT&I and PM here. [MCR-1912]

1926. The PM places an order with the General Railway Signal Company covering one 36-lever Model-2 unit lever type electric interlocking machine, having 26 working levers and 10 spare spaces, for installation at Carleton, MI at the crossing of the Pere Marquette, Detroit Toledo & Ironton, and the Pennsylvania. This order also includes 16 Model-5A switch machines, 4 Type-G color light signals; 7 Type-D color-light signals, 2 Type-B position-light signals, 5 Type-L color light dwarf signals, 1 Type-C position-light dwarf signal, 1 Type-F color light dwarf signal, as well as instrument cases, track relays, track transformers, clock-work time releases, relays, circuit controllers, power-off relays, switch indicators and relay boxes. [RSG-1926-10]

1926. PM builds a new interlocking tower and plant at Carleton, which includes 26 electric levers and color-light signals. [RSC-1927]

1970's. The Penn Central left the C&O main line just north of the Carleton interlocking tower. The junction was controlled by the Carleton interlocker. The PC single track to Lincoln yard was a train order operation with an APB (absolute-permissive-block) system. Sometimes, a northbound PC train would get stopped by their own signal and had to radio to Penford for authority to pass it. When this happened, they tied up the Carleton interlocking for a while. [DH]