The Difference Between Single-circuit Towers And Double-circuit Towers ‌

A single-circuit tower refers to a single tower on which only one three-phase transmission circuit is erected, while a double-circuit tower refers to a single tower on which two independent three-phase circuits are erected, allowing for the simultaneous transmission of two paths of electrical energy.
core difference
Number of circuits
Single circuit: It carries only one three-phase power supply circuit (A, B, C phases).
Double-circuit: It carries two independent three-phase circuits, equivalent to two lines "sharing" one tower.
Structural features
The single-circuit tower structure is relatively simple, commonly featuring arrangements in the shape of "干" or "上" characters.
The double-circuit tower is taller and wider, with more layers of cross arms (such as three or four layers), and a larger number of conductors and insulators.
Application scenario
Single-circuit: suitable for ordinary lines or power supply to small and medium-sized users where power supply reliability is not highly required.
Dual-circuit: used in areas with high load and high reliability requirements (such as urban backbone networks and important substations), to increase transmission capacity and save land for line corridors.
Power supply reliability
The dual-circuit design ensures continuity by allowing one circuit to continue supplying power while the other is under maintenance or in case of a fault.
The presence of "simultaneous tripping" risks (such as lightning strikes) in double-circuit lines on the same tower requires optimization of safety through differential insulation design or reduction of grounding resistance.