In-line passive barrier for intrinsically safe communication network

An in-line passive isolation barrier for megahertz serial digital data communication networks comprising:

• a housing having a first terminal set receiving a first conductor pair from non-intrinsically safe network and a second terminal set for receiving a second conductor pair from an intrinsically safe network, the housing further containing:
• a DC blocking element in series between the first and second terminal sets;
• a fusible link having a first end joined through the first terminal set to a first conductor of the first conductor pair;
• a bi-polar voltage sensitive conductor shunting a second end of the fusible link and a second conductor of the first conductor pair at substantially equal positive and negative voltages;
• and
• a matching network in series between the first and second terminal sets to substantially match the impendence of the barrier at the first and second terminal sets to media of the non-intrinsically safe network and intrinsically safe network, respectively.