System to monitor multiple fuel dispensers and fuel supply tank

Claim 1

For use in combination with apparatus to monitor liquid inventory in a storage tank, and employing multiple dispenser means to dispense liquid fuel received from the tank, there being pulse generating means operatively connected with the dispenser means to generate pulses in accordance with increments of fuel dispensed, the combination comprising a) interface means operatively connected to said pulse generating means to sense said pulses and to convert said pulses into first volume indicating data valves corresponding to said respective multiple dispenser means, b) said interface means also operatively connected to second means at said storage tank to: i) sense liquid level in said storage tank and to provide second volume indicating data valves, during predetermined time interval, ii) sense volume of liquid fuel delivered to the storage tank during said predetermined time interval, for determining liquid fuel loss or theft, c) and computer means operatively connected to said interface means to control the interface means, said interface means having processing means for receiving and processing said first and second data valves to provide an output or outputs indicative of fuel loss from said storage tank, and also indicative of liquid fuel delivered to said storage tank for determining liquid fuel loss or theft, d) said interface means including circuitry for selective operation in at least two each of the following modes: i) data compute mode, ii) command mode, to receive commands from the computer means for controlling data transmission and reception, iii) tank level monitor mode to receive said pulses as per a) above and to sense said liquid level in said storage tank and liquid fuel volume, as per b) above, iv) parallel port pass-through mode for transmitting data to a data recorder, e) said circuitry including ports corresponding to each of said modes of operation, f) and including said storage tank and said second means which are located at the storage tank.