When the bridge is in use, it often fails due to various situations, but when the failure occurs, it cannot prepare to make judgments, which causes a great loss. This requires timely response to the failure. It makes judgments, so what is the way to judge when the bridge is broken?

(1) When the insulation resistance of one or several cores of the cable to the ground is measured, or the insulation resistance between the core and the core is less than 100Ω, it is a low resistance grounding or short circuit fault.

(2) When the insulation resistance of one or several cores of the cable to the ground is measured, or the insulation resistance between the core and the core is much lower than the normal value, but higher than 100Ω, it is a high resistance ground fault.

(3) When the one or several cores of the rocking cable have high or normal insulation resistance to the ground, a conductor continuity test should be conducted to check whether there is a broken wire in the Nanjing bridge, and if there is a broken wire failure.

(4) When the one-core or several-core conductors of the telemetry cable are discontinuous and are grounded through resistance, it is a broken wire and a ground fault.

(5) Flashover failures mostly occur in preventive voltage tests, and most of them occur at the cable terminals and intermediate connectors. Flashover sometimes occurs multiple times in a row, with intervals of a few seconds to a few minutes each time.