Blackburn FB4E12 FLEXIBLE BRAID 307.2KCMIL, LEN 12IN

The FB4E12 is a flexible bonding braid rated 307.2 kcmil with a 12 inch length. It is sold as a single piece, one braid per order, so if you are bonding multiple sections of raceway or several pieces of equipment you need one per connection point.

A braided bonding jumper like the Blackburn FB4E12 carries fault current across a joint that has to move or that does not give a reliable metal to metal path, such as expansion fittings in conduit runs, equipment on vibration isolators, hinged enclosure doors, transformer and switchgear connections, and bonding across flexible conduit. The braid construction lets the connection flex without work hardening or breaking a solid conductor.

Country of origin on the FB4E12 is the United States. That matters on federally funded, military, and Buy American public works jobs where domestic origin has to be documented for the grounding and bonding material.

Use the braid. Across an expansion or deflection fitting the joint moves, and a solid or stranded copper conductor fatigues and eventually opens at the terminations. A flexible braid such as the Blackburn FB4E12, rated 307.2 kcmil in a 12 inch length, absorbs that movement while keeping a low impedance fault path. Plain wire is fine where the bonded parts are fixed relative to each other.

The FB4E12 is supplied as a 12 inch flexible braid jumper, one per package. Fasteners for the structure or enclosure it lands on, such as bolts, nuts and washers, are a separate item and are sized to the equipment you are bonding to.