Field device interface with network protection mechanism

A field device interface module comprising:

• a connector configured to operably couple to a computer;
• a plurality of terminals operably coupleable to a field device;
• a protocol interface module coupled to the plurality of terminals and configured to generate signals in accordance with a process communication protocol;
• a controller coupled to the protocol interface module;
• a power supply module coupled to the plurality of terminals and coupled to the controller, the power supply module being operably coupled to the connector;
• wherein the controller is configured to measure a voltage across the plurality of terminals and selectively cause the power supply module to provide power to the field device;
• wherein the field device interface module is powered through the connector;
• and wherein the power supply module includes a power storage device.