Flow signal monitor for a fuel dispensing system

Abstract

The present invention relates to a flow signal monitoring system for monitoring data signals in a data wire between fuel dispensers and the dispenser controller for collecting, storing, and later down-loading information relating flow quantity signals. The system includes an electronic communication translator which is attached to the wire. The design of the monitoring system is such that it is coupled to the data wire, however, it is electrically isolated from the data wire. When the dispenser and remote dispenser controller are communicating in current loop communication protocol, the system uses a configuration circuit with an opto-coupler having a light emitting diode and transistor for transforming the data signals into corresponding computer logic signals. When the dispenser and controller are communicating in voltage level communication protocol, a comparator is used to transform the data signals into corresponding computer logic signals. The computer logic signals are sent to a microprocessor with read-only memory and read-and-write memory for processing. The system further includes a data field selector which instructs the microprocessor to select and process data fields relating to flow quantity, and to discard all other data signals. Information on the amount of fuel dispensed at each fueling position in the dispenser is stored in memory. This information can be down-loaded to other devices including tank monitors, printer, and display devices.