Petrol pump storage tank level indicator - push button operated meter adjusted to suit pressure changes

摘要

A petrol pump installation with an underground storage tank has a filling line, a ventilation line, and a discharge line, the latter connected to the dispensing pump and nozzle, via a check valve. A branch preceding this check valve and of much smaller diameter is connected to a level indicating meter incorporated in the housing of he petrol pump so that it can be read by the pump operator. Incorporated in the small diameter line, close to the meter i a push button operated relief valve so that the operator can reset the meter to allow for pressure changes within the tank.