English to Russian Tech/Engineering Construction / Civil Engineering rail LRT signals

As noted previously, mechanical train stops are generally considered obsolete technology, but are found on older systems. The key component of the mechanical train stop is the driving arm, which is pulled to the clear position a inch [12 mm] below the top of the running rail by either an air or electric motor and returned to its tripping position by a spring. Mechanical train stops are usually mounted on plates midway between two rails with the operative arm outside either the right-hand or the left-hand rail.