Example apparatus to communicatively couple three-wire field devices to controllers in a process control system are disclosed. An example terminal block is disclosed that includes a first interface having three termination points to terminate each of three wires from a three-wire field device. The example, terminal block further includes a second interface to removably receive a first termination module that is to communicate with the three-wire field device using a first communication protocol and to communicate with a controller via a shared bus of a termination panel using a second communication protocol different than the first communication protocol.
