A process variable transmitter comprising: a sensor terminal block comprising a plurality of sensor line connectors adapted to connect to sensor lines from at least one process variable sensor, a removable standard power terminal block which comprises at least two power line connectors (317, 319) adapted for connecting to at least two respective power lines (128, 130) that are external to the standard power terminal block and provide power to the standard power terminal block; and a removable transient power terminal block which comprises at least two power line connectors adapted for connecting to at least two respective power lines, wherein the removable transient power terminal block further comprises at least two power terminals and transient power protection components electrically coupled between the at least two power line connectors and the at least two power terminals, the transient power protection components being adapted for suppressing transient power above a threshold limit to limit the power reaching the at least two power terminals; wherein the sensor terminal block defines a reception area that in a first instance is adapted to accept the removable standard power terminal block and in a second instance to accept the removable transient power terminal block; one of the removable standard power terminal block and the removable transient power terminal block being inserted in the reception area of the sensor terminal block; the process variable transmitter being characterized in that a surface of the sensor terminal block and one of the removable standard power terminal block or the removable transient power terminal block together define a partial well for wires that are to be connected to power line connectors (317, 319). a sensor terminal block comprising a plurality of sensor line connectors adapted to connect to sensor lines from at least one process variable sensor, a removable standard power terminal block which comprises at least two power line connectors (317, 319) adapted for connecting to at least two respective power lines (128, 130) that are external to the standard power terminal block and provide power to the standard power terminal block; and a removable transient power terminal block which comprises at least two power line connectors adapted for connecting to at least two respective power lines, wherein the removable transient power terminal block further comprises at least two power terminals and transient power protection components electrically coupled between the at least two power line connectors and the at least two power terminals, the transient power protection components being adapted for suppressing transient power above a threshold limit to limit the power reaching the at least two power terminals; wherein the sensor terminal block defines a reception area that in a first instance is adapted to accept the removable standard power terminal block and in a second instance to accept the removable transient power terminal block; one of the removable standard power terminal block and the removable transient power terminal block being inserted in the reception area of the sensor terminal block; the process variable transmitter being characterized in that a surface of the sensor terminal block and one of the removable standard power terminal block or the removable transient power terminal block together define a partial well for wires that are to be connected to power line connectors (317, 319).