A pressure sensor module (50) and method for preinstallation without a converter module. The pressure sensor module (50) is hermetically sealed and can remain undamaged in an installation environment without a converter module. The pressure sensor module (50) can be assembled later with a converter module in the installation environment. The pressure sensor module (50) includes an isolator (54), a pressure sensor (58) and a circuit (60) that provides a bus (64) for energization, control and a digital pressure output. The bus (64) is connected to contacts (68) in an insulating feedthrough. An integrally formed hermetic external support structure surrounds the pressure sensor (58) and circuit (60). The hermetic external support structure has a threaded process fluid inlet (74) around the isolator (54), and a threaded support sleeve (76) supporting the feedthrough.