Monitor for fluid dispensing system

A method of monitoring an operation of a fluid dispensing system controlling flow of a fluid through a fluid dispenser, the fluid dispenser including a sensor producing an input signal representing pressure of the fluid in the fluid dispenser, the method comprising the steps of:

• storing an alarm limit value representing a limit of a range of pressures of the fluid;
• storing a warning limit value of the pressure, the warning limit value having a magnitude between the alarm limit value and an acceptable value of the pressure;
• periodically sampling the input signal during a sampling period to detect sampled values of the pressure of the fluid in the dispenser;
• comparing each sampled value to the alarm and warning limit values;
• and
• producing a warning error code in response to predetermined relationships between the sampled values and the alarm and warning limit values.

A method of monitoring an operation of a fluid dispensing system controlling flow of a fluid through a fluid dispenser, the fluid dispenser including a sensor producing an input signal representing pressure of the fluid in the fluid dispenser, the monitoring occurring over an ON time period during which fluid is being dispensed and an OFF time period during which fluid is not being dispensed, the method comprising the steps of:

• periodically sampling from a start of the ON time period, the input signal to produce sampled values of the pressure of the fluid in the fluid dispenser;
• periodically comparing the sampled values of the input signal with a reference value representing an acceptable pressure value during the ON time period;
• measuring a turn ON transition time period from the start of the ON time period;
• and
• producing a turn ON time error code in response to the turn ON transition time exceeding a value of a reference turn ON transition time period prior to a sampled value of the input signal being approximately equal to the reference pressure value.

A method of monitoring an operation of a fluid dispensing system controlling flow of a fluid through a fluid dispenser, the fluid dispenser including a sensor producing an input signal representing pressure of the fluid in the fluid dispenser, the monitoring occurring over an ON time period during which fluid is being dispensed and an OFF time period during which fluid is not being dispensed, the method comprising the steps of:

• periodically sampling from a start of the OFF time period, the input signal to produce sampled values of the pressure of the fluid in the fluid dispenser;
• periodically comparing the sampled values of the input signal with a reference value representing an acceptable pressure during the OFF time period;
• measuring a turn OFF transition time period from the start of the OFF time period;
• and
• producing a turn OFF time error code in response to the turn OFF transition time period exceeding a value of a reference turn OFF transition time prior to a sampled value being approximately equal to the reference value.

A method of monitoring an operation of a fluid dispensing system controlling flow of a fluid through a fluid dispenser connected to a fluid supply, the fluid dispenser including a sensor producing an input signal having values representing a characteristic of fluid flow through the fluid dispenser, the fluid dispensing system providing an ON time period during which fluid is being dispensed and an OFF time period during which fluid is not being dispensed, the method comprising the steps of:

• storing an alarm limit value of the characteristic of fluid flow;
• periodically sampling the input signal over a sampling period during the OFF time period to detect sampled characteristic values of fluid flow;
• periodically comparing the sampled characteristic values to the alarm limit value;
• and
• producing a static pressure alarm error code in response to predetermined relationships between sampled characteristic values and the alarm limit value.

A method of monitoring an operation of a fluid dispensing system controlling flow of a fluid through a fluid dispenser connected to a fluid supply, the fluid dispenser including a sensor producing an input signal representing pressure of the fluid in the fluid dispenser, the fluid dispensing system providing an ON time period during which fluid is being dispensed and an OFF time period during which fluid is not being dispensed, the method comprising the steps of:

• storing an alarm limit value representing a limit of an acceptable range of pressures of the fluid during the OFF time period;
• periodically sampling the input signal over a sampling period during the OFF time period to detect sample values of the pressure;
• periodically comparing the sample values to the alarm limit value;
• and
• producing a static pressure alarm error code in response to predetermined relationships between sampled values and the alarm limit value.

The method of 28 claim further comprising the steps of:

• storing a high alarm limit value and a low alarm limit value representing respective alarm limits above and below a desired value of the pressure;
• periodically comparing the sampled values to the high and low alarm limit values;
• producing a high alarm pressure quality indicator in response to each of the sampled values exceeding the high alarm limit value;
• counting each high alarm pressure quality indicator produced during the sampling period;
• producing a low alarm pressure quality indicator in response to each of the sampled values exceeding the low alarm limit value;
• counting each low alarm pressure quality indicator produced during the sampling period;
• and
• producing the static pressure alarm error code in response to counting a predetermined number of occurrences of both the high and low alarm pressure quality indicators.

A method of calibrating a control monitoring flow characteristics of a fluid, the control sensing a pressure within a fluid dispenser connected to a fluid supply, the fluid dispenser having a pressure sensor located inside the fluid dispenser between a nozzle and a calibrated orifice through which the fluid passes, the fluid sensor producing a pressure signal representing a static pressure value during an OFF time period during which fluid is not being dispensed and a firing pressure value during an ON time period during which fluid is being dispensed from the fluid sensor the method comprising the steps of:

• storing a first input signal representing a nozzle size and a desired flowrate;
• storing a second input signal representing a desired static pressure value;
• storing a third signal representing the calibrated orifice;
• calculating a theoretical firing pressure value in response to the input signals;
• dispensing fluid from the nozzle during a predetermined number of the ON time periods and terminating the dispensing of fluid through the nozzle during the predetermined number of OFF time periods;
• sampling the pressure signal during each of the predetermined number of ON time periods to detect firing pressure values during the ON time periods;
• averaging the firing pressure values over the predetermined number ON time periods to provide an average firing pressure value;
• comparing the average firing pressure value with the theoretical firing pressure value;
• providing an error signal in response to a difference between the average firing pressure value and the theoretical firing pressure value exceeding a predetermined magnitude;
• and
• calculating a set of pressure limit values using the average firing pressure value in response to the difference between the average firing pressure value and the theoretical firing pressure value being less than the predetermined magnitude.