Surge arrester circuit and housing therefor

A circuit for limiting voltage surges across a service line in a multiphase load center, panelboard or the like, the circuit comprising:

• at least two high potential terminals being adapted for connecting to at least two corresponding high potential lines;
• a low potential terminal being adapted for connecting to a low potential means;
• a first plurality of varistors connecting in parallel to one another between the first high potential terminal and the low potential terminal;
• a first plurality of fuses having a number of fuses equal to the number of varistors in the first plurality of varistors, each fuse connecting in series to a different varistor of the first plurality of varistors to form a one to one correspondence, each fuse opening the circuit therethrough upon failure of the varistor connecting in series therewith;
• a second plurality of varistors connecting in parallel to one another between the second high potential terminal and the low potential terminal;
• a second plurality of fuses having a number of fuses equal to the number of varistors in the second plurality of varistors, each fuse of the second plurality of fuses connecting in series to a different varistor of the second plurality of varistors to form a one to one correspondence, each fuse of the second plurality of fuses opening the circuit therethrough upon failure of the varistor connecting in series therewith;
• and
• means for monitoring the status condition of the fuses, the monitoring means electrically connecting to the fuses.

A surge arrester for use with a service line within an electrical distribution device, the surge arrestor comprising:

• a housing made of an electrically insulating material, the housing having a base adapted for connection with the distribution device;
• at least one high potential terminal being adapted for connection to at least one corresponding high potential line, each high potential terminal extending through the housing;
• a low potential terminal being adapted for connecting to a low potential means, the low potential terminal extending through the housing;
• a plurality of varistors being enclosed within the housing and connecting in parallel to one another between each high potential terminal and the low potential terminal;
• a plurality of fuses being enclosed within the housing and having a number of fuses equal to the number of varistors in the plurality of varistors, each fuse connecting in series to a different varistor of the plurality of varistors to form a one to one correspondence, each fuse opening the circuit therethrough upon failure of the varistor connecting in series therewith;
• and
• means for monitoring the status condition of the fuses, the monitoring means being enclosed within the housing with a display externally discernable.