RF adapter for field device with low voltage intrinsic safety clamping

An adapter for coupling to a process control transmitter of the type used to monitor a process variable in an industrial process, the adapter comprising:

• a first adapter connection configured to couple to a first wire of a two wire process control loop;
• a second adapter connection configured to couple to a first transmitter connection of a process control transmitter;
• a third adapter connection configured to couple to a second transmitter connection of the process control transmitter and to a second wire of the process control loop, wherein the third adapter connection is used to communicate information on the two wire process control loop;
• wireless communication circuitry configured to provide wireless communication for the process control transmitter, wherein the first and second adapter connections are used to power the wireless communication circuitry;
• and
• intrinsic safety circuitry coupled to at least one of the first, second and third adapter connections configured to limit energy transfer to a value which is less than an intrinsic safety value, wherein the two wire loop is used for powering the process control transmitter and powering the wireless communication circuitry, and the two wire process control loop is further configured to ca information communicated from the third adapter connection.