Track circuit interrupter

A track circuit interrupter may be fitted at catch points, trap points or buffer stops to maintain a track circuit in the 'occupied' state in the event of a derailment. The track circuit remains de-energised until the interrupter is replaced.

An insulated track circuit interrupter fitted to trap points

GK/RT0011 specifies the requirements for the provision of track circuit interrupters. ^[1]

Interrupter drawn as two filled triangles. Assume train has overrun 53 signal and 52A trap points and interrupter shows DBT T.C. on Down Line as blocked (twin red lights).