초록 ▼

A fail-safe fluid transfer control apparatus has full redundancy in the response to various inputs such as overfill probe signals, ground detection signals, and the like. Independent microprocessor controllers independently evaluate the inputs and each output control signals to close a respective re

A fail-safe fluid transfer control apparatus has full redundancy in the response to various inputs such as overfill probe signals, ground detection signals, and the like. Independent microprocessor controllers independently evaluate the inputs and each output control signals to close a respective relay when the inputs indicate that fluid transfer may commence. The relays are arranged in series such that both must be closed for a fluid transfer to commence. The control signals from each controller include a static signal and an alternating signal, both of which must be properly output to close its respective relay. Each controller monitors the state of each relay, and discontinues its control signals if either relay appears to be malfunctioning. Each controller runs an different, independently written firmware program to process the detected inputs to prevent a common firmware error. An optical bypass key replaces conventional mechanical keys and transmits an optically encoded signal to the controller for establishing a bypass condition. A preheating circuit is also provided for providing a dynamic voltage supply to standard thermistor probes which may be encountered.

대표청구항 ▼

[ What is claimed is:] [1.] A fluid transfer control apparatus for controlling a transfer of fluid from a fluid source to a receiving container and for detecting and responding to an input signal which indicates whether fluid transfer should occur, the apparatus comprising:a first switch responsive

[ What is claimed is:] [1.] A fluid transfer control apparatus for controlling a transfer of fluid from a fluid source to a receiving container and for detecting and responding to an input signal which indicates whether fluid transfer should occur, the apparatus comprising:a first switch responsive to a first control signal which switches to a first switch position when the first control signal is received,a second switch responsive to a second control signal which switches to a first switch position when the second control signal is received, and which is arranged in conjunction with the first switch such that fluid transfer to said container is prevented unless the first switch is in its first switch position and the second switch is in its first switch position;a first controller which is responsive to the input signal and which outputs the first control signal when the input signal indicates that fluid transfer should occur; anda second controller responsive to the input signal which outputs the second control signal when the input signal indicates that fluid transfer should occur.