DETECTOR DE TUNEL PARA LOCOMOTIVA TENDO MOTOR PRINCIPAL TERMICO A BORDO E APERFEICOAMENTO EM LOCOMOTIVA TENDO SISTEMA DE PROPULSAO

The propulsion control system of a diesel-electric locomotive includes means responsive to the respective temperatures of the coolant and the lubricant of the locomotive engine for automatically indicating that the locomotive is in a tunnel if the coolant temperature exceeds an abnormally high magnitude and is higher than a variable reference level that depends on the lubricant temperature. When a tunnel is thus detected, the conventional overtemperature-responsive deration function of the propulsion control system is temporarily suppressed until the coolant temperature rises to a threshold that is higher than the preset overtemperature threshold at which deration is normally initiated.