Hydrocarbon sensor diagnostic method
AssigneeGilbarco Inc.
InventorSeifollah S. Nanaji
Life of this patent
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Abstract
A vapor recovery system in a fuel dispenser includes the ability to self diagnose the continued viability of a hydrocarbon sensor positioned within the vapor recovery system. A control system associated with the vapor recovery system performs a series of tests including passing pure air over the hydrocarbon sensor and passing a gas known to have hydrocarbons therein over the sensor and evaluating the output of the sensor to see if expected values are output. If the measured values are not within tolerable limits, an alarm is generated.
Claims38
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- and
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor,
- wherein the step of performing a diagnostic test on said sensor comprises passing air lacking hydrocarbons over said sensor to create a second output of said sensor and comparing the first output to the second output.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- and
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor,
- wherein the step of performing a diagnostic test on said sensor comprises passing air known to contain hydrocarbons over said sensor and evaluating a second output from said sensor.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- and periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor,
- wherein the step of performing a diagnostic test on said sensor comprises checking a power input to said sensor.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- and
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor,
- wherein the step of performing a diagnostic test on said sensor comprises the steps of varying a power input to said sensor and checking the output of said sensor to determine if the output varies in response to the varying power input.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor;
- and
- during a single fueling transaction, comparing an initial output from said sensor with a subsequent output from said sensor.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor;
- and
- determining if said first output is within a predetermined range.
A method for diagnosing an operative status of a system for determining hydrocarbon concentration in a vapor recovery system, said method comprising:
- delivering fuel through a fuel dispenser during a fueling transaction;
- recovering vapor during said fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a first output of a sensor in said system for determining hydrocarbon concentration;
- determining if said fueling transaction is a new fueling transaction;
- measuring the hydrocarbon concentration in the recovered vapor by examining a second output of said sensor for determining hydrocarbon concentration;
- determining if said first output is within a predetermined range of said second output;
- determining if said fueling transaction is the appropriate fueling transaction to trigger a diagnostic test;
- determining if said second output is within a predetermined range;
- and
- periodically performing a diagnostic test on said sensor to evaluate the performance of said sensor.
A vapor recovery system comprising:
- a) a vapor recovery line;
- b) a sensor bearing on hydrocarbon concentration and producing an output indicative of hydrocarbon concentration within said vapor recovery line;
- and
- c) a control system associated with said vapor return system, wherein said control system periodically runs diagnostics to evaluate the performance of said sensor,
- wherein said control system evaluates the performance of said sensor by passing air substantially lacking hydrocarbons over said sensor to produce an output At and comparing At to an output derived during a fueling transaction.
A vapor recovery system comprising:
- a) a vapor recovery line;
- b) a sensor bearing on hydrocarbon concentration and producing an output indicative of hydrocarbon concentration within said vapor recovery line;
- and
- c) a control system associated with said vapor return system, wherein said control system periodically runs diagnostics to evaluate the performance of said sensor,
- wherein said control system further compares an initial output associated with a beginning of a fueling transaction to a subsequent output associated with the same transaction.
A fuel dispenser comprising:
- a) a fuel delivery line;
- and
- b) a vapor recovery system associated with said fuel dispensing means, said vapor recovery system comprising:
- i) a sensor bearing on a hydrocarbon concentration level;
- ii) a vapor return line, said sensor associated with said vapor return line and capable of measuring hydrocarbon concentrations therein;
- and
- iii) a control system communicatively coupled to said sensor wherein said control system periodically tests said sensor to determine a present operating condition of said sensor,
- wherein said sensor passes an initial measurement to said control system and said control system determines if said sensor has measured a new transaction.
Dependencies are inferred from the claim text.