A cable installation method where the metallic sheaths or screens of three-phase single-core cables are interrupted and cross-connected at regular intervals along the route. This transposition cancels out the induced circulating currents in the sheaths, eliminating a major source of heat and allowing the cables to carry their maximum rated load current.
Heard on the job
The link boxes in the joint bays are configured for cross-bonding to keep the sheath losses down on the transmission circuit.
Insider tip
Failure to properly cross-bond a long transmission cable run will result in massive circulating currents in the sheaths, quickly melting the outer jacket and destroying the cable.