LEAKAGE DETECTION UNIT WITH VARIABLE SIZE ORIFICE

The present invention relates to leakage detection unit (100) comprise of an upper housing (5), a lower housing (6) accommodating an electromechanical valve (1), a pump assembly (2), a pressure sensor (3) and a bush (4), wherein the pump assembly (2) includes a pump that permits flow of air that, due to which pressure in passage of the pump becomes constant after a time interval and that pressure is considered as reference pressure. The pressure is measured by help of the pressure sensor (3) and in case the measured pressure is not equal or above to the reference pressure than there is leakage in the isolation valve (100), whereas in case the measured pressure is equal or above the reference pressure that there is no leakage or some permissible amount of leakage in the fuel tank within the time interval.