TEMPERATURE COMPENSATED PRESSURE SWITCH (TCPS)

• US 20080127725A1
• Filed: 11/30/2007
• Published: 06/05/2008
• Est. Priority Date: 11/30/2006
• Status: Active Grant

• Current Assignee: MASS Systems Co.
• Original Assignee: MASS Systems Co.
• Inventors: Sitabkhan, Abdul N., Mallari, Michael A.
• Granted Patent: US 8,443,650 B2
• Time in Patent Office: Days
• US Class Current: 73/149
• CPC Class Codes: G01F 22/02 involving measurement of pressure
• CPC Class Codes: G01F 25/0084 for measuring volume

Abstract

A temperature compensated pressure switch (“TCPS”) with thermal lag compensation, trend indication, and forecast analysis. The TCPS has a first control unit, a pressure sensor connected to the first control unit outputting a first pressure data, a temperature sensor connected to the first control unit outputting a first temperature data, and a first storage unit connected to the first control unit storing: minimum and maximum pressure data corresponding to temperature data and rate of temperature change values. The first control unit can substitute a second temperature data, for the first temperature data for a period of time. The first control unit also outputs a first signal indicating the amount of material is acceptable when the first pressure data is above the minimum pressure data and outputs a second signal indicating the amount of material is unacceptable when the first pressure data is not above the minimum pressure data.

Claims

1. A temperature compensated pressure switch for determining and analyzing a amount of material within a vessel comprising:

a first control unit;

a pressure sensor connected to the first control unit outputting a first pressure data;

a temperature sensor connected to the first control unit outputting a first temperature data; and

a first storage unit connected to the first control unit storing

minimum pressure data corresponding to temperature data, the first temperature data at periodic intervals, maximum rate of temperature change values, first substitute rate of temperature change values corresponding to maximum rate of temperature change values, minimum rates of temperature change values, and second substitute rate of temperature change values corresponding to minimum rates of temperature change values,

wherein when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is above a maximum rate of temperature change value, the first control unit substitutes a second temperature data, based on a first substitute rate of temperature change value, for the first temperature data for a period of time, and when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is below a minimum rate of temperature change value, the first control unit substitutes a second temperature data, based on a second substitute rate of temperature change value, for the first temperature data for a period of time, and

wherein the first control unit outputs a first signal indicating the amount of material is acceptable when the first pressure data is above the minimum pressure data and outputs a second signal indicating the amount of material is unacceptable when the first pressure data is not above the minimum pressure data.

2. The temperature compensated pressure switch of claim 1 wherein the first storage unit further stores maximum pressure data corresponding to temperature data, and the first control unit outputs the first signal indicating the amount of material is acceptable when the first pressure data is below the maximum pressure data and the second signal indicating the amount of material is unacceptable when the first pressure data is not below the maximum pressure data.

3. The temperature compensated pressure switch of claim 2 further comprising a voltage regulator connected to the temperature sensor, the pressure sensor, and the storage unit.

4. The temperature compensated pressure switch of claim 3 further comprising a test module connected to the first control unit and the pressure sensor, wherein when the test module is activated, the first control unit receives a third pressure data substituted for the first temperature data, the third pressure data indicating a pressure below the minimum pressure data or above the maximum pressure data.

5. The temperature compensated pressure switch of claim 4 further comprising:

an output driver connected to the first control unit receiving the first signal or the second signal output by the first control unit and transmitting the first signal or the second signal to an external apparatus; and

an electro-magnetic interference protection unit connected to the output driver and the voltage regulator.

6. The temperature compensated pressure switch of claim 5 further comprising:

a second control unit connected to the first control unit; and

a second storage unit connected to the second control unit,

wherein the second control unit stores the first pressure data and the first temperature data in the second storage unit at periods of time, and

wherein the second control unit determines whether there is a leak in the vessel by comparing the first pressure data and the first temperature data with the first pressure data and the first temperature data stored in the second storage unit.

7. The temperature compensated pressure switch of claim 6 wherein when the second control unit determines there is a leak in the vessel, the second control unit determines when the vessel will need to be serviced based on the first pressure data, the first temperature data, the first pressure data stored in the second storage unit, and the first temperature data stored in the second storage unit.

8. The temperature compensated pressure switch of claim 7 further comprising a wireless transmission unit connected to the second control unit allowing the second control unit to communicate with an external apparatus.

9. The temperature compensated pressure switch of claim 8 wherein the first control unit includes a first communication port allowing the first control unit and the first storage unit to be configured, and the second control unit includes a second communication port allowing the second control unit and the second storage unit to be configured.

10. The temperature compensated pressure switch of claim 2 further comprising a wireless transmission unit connected to the first control unit allowing the first control unit to communicate with an external apparatus.

11. The temperature compensated pressure switch of claim 2 wherein the first control unit stores the first pressure data and the first temperature data in the first storage unit at periods of time and the second control unit determines whether there is a leak in the vessel by comparing the first pressure data and the first temperature data with the first pressure data and the first temperature data stored in the first storage unit, and when the second control unit determines there is a leak in the vessel, the first control unit determines when the vessel will need to be serviced based on the first pressure data, the first temperature data, the first pressure data stored in the first storage unit, and the first temperature data stored in the first storage unit.

12. The temperature compensated pressure switch of claim 2 wherein the first storage unit is an EEPROM.

13. The temperature compensated pressure switch of claim 2 further comprising:

an amplifier connected to the pressure sensor; and

an analog to digital converter connected to the amplifier and the first control unit.

14. A temperature compensated pressure switch for determining and analyzing a amount of material within a vessel comprising:

a first control unit;

a wireless transmission unit connected to the first control unit;

a pressure sensor connected to the first control unit outputting a first pressure data;

a temperature sensor connected to the first control unit outputting a first temperature data;

a first storage unit connected to the first control unit storing

minimum pressure data and maximum pressure data corresponding to temperature data, the first temperature data at periodic intervals, maximum rate of temperature change values, first substitute rate of temperature change values corresponding to maximum rate of temperature change values, minimum rates of temperature change values, and second substitute rate of temperature change values corresponding to minimum rates of temperature change values,

wherein when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is above a maximum rate of temperature change value, the first control unit substitutes a second temperature data, based on a first substitute rate of temperature change value, for the first temperature data for a period of time, and when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is below a minimum rate of temperature change value, the first control unit substitutes a second temperature data, based on a second substitute rate of temperature change value, for the first temperature data for a period of time, and

wherein the first control unit outputs a first signal indicating the amount of material is acceptable when the first pressure data is above the minimum pressure data and below the maximum pressure data and outputs a second signal indicating the amount of material is unacceptable when the first pressure data is not above the minimum pressure data and not below the maximum pressure data.

15. The temperature compensated pressure switch of claim 14 further comprising a test module connected to the first control unit and the pressure sensor, wherein when the test module is activated, the first control unit receives a third pressure data substituted for the first temperature data, the third pressure data indicating a pressure below the minimum pressure data or above the maximum pressure data.

16. The temperature compensated pressure switch of claim 15 further comprising an output driver connected to the first control unit receiving the first signal or the second signal output by the first control unit and transmitting the first signal or the second signal to an external apparatus.

17. The temperature compensated pressure switch of claim 16 further comprising:

a voltage regulator connected to the temperature sensor, the pressure sensor, and the storage unit; and

an electro-magnetic interference protection unit connected to the output driver and the voltage regulator.

18. The temperature compensated pressure switch of claim 14 further comprising:

a second control unit connected between the first control unit and the wireless transmission unit; and

a second storage unit connected to the second control unit, wherein the second control unit stores the first pressure data and the first temperature data in the second storage unit at periods of time, and the second control unit determines whether there is a leak in the vessel, and when there is a leak in the vessel, the second control unit determines when the vessel will need to be serviced by comparing the first pressure data and the first temperature data with the first pressure data and the first temperature data stored in the second storage unit.

19. The temperature compensated pressure switch of claim 14 wherein the first control unit stores the first pressure data and the first temperature data in the first storage unit at periods of time and the first control unit determines whether there is a leak in the vessel, and when there is a leak in the vessel, the first control unit determines when the vessel will need to be serviced by comparing the first pressure data and the first temperature data with the first pressure data and the first temperature data stored in the first storage unit.

20. The temperature compensated pressure switch of claim 18 wherein the first control unit includes a first communication port allowing the first control unit and the first storage unit to be configured, and the second control unit includes a second communication port allowing the second control unit and the second storage unit to be configured.

21. The temperature compensated pressure switch of claim 14 further comprising:

an amplifier connected to the pressure sensor; and

an analog to digital converter connected to the amplifier and the first control unit.

22. A system for storing and monitoring a amount of material comprising:

a vessel for storing the material; and

a temperature compensated pressure switch mounted on the vessel comprising;

a first control unit;

a pressure sensor connected to the first control unit outputting pressure data;

a temperature sensor connected to the first control unit outputting a first temperature data; and

a first storage unit connected to the first control unit storing

minimum pressure data corresponding to temperature data, the first temperature data at periodic intervals, maximum rate of temperature change values, first substitute rate of temperature change values corresponding to maximum rate of temperature change values, minimum rates of temperature change values, and second substitute rate of temperature change values corresponding to minimum rates of temperature change values,

wherein when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is above a maximum rate of temperature change value, the first control unit substitutes a second temperature data, based on a first substitute rate of temperature change value, for the first temperature data for a period of time, and when the first control unit determines, based on the first temperature data stored in the first storage unit, that a rate of temperature change value is below a minimum rate of temperature change value, the first control unit substitutes a second temperature data, based on a second substitute rate of temperature change value, for the first temperature data for a period of time, and

wherein the first control unit outputs a first signal indicating the amount of material is acceptable when the pressure data is above the minimum pressure data and outputs a second signal indicating the amount of material is unacceptable when the pressure data is not above the minimum pressure data.

23. The system of claim 22 wherein the first storage unit further stores maximum pressure data corresponding to temperature data and the first control unit outputs a first signal when the pressure data is below the maximum pressure data and outputs a second signal when the pressure data is not below the maximum pressure data.

24. The system of claim 23 wherein the temperature compensated pressure switch further comprises:

a second control unit connected to the first control unit;

a second storage unit connected to the second control unit; and

a wireless transmission unit connected to the second control unit allowing the second control unit to communicate with an external apparatus.

25. The system of claim 22 wherein the first storage unit further comprises a wireless transmission unit connected to the first control unit allowing the first control unit to communicate with an external apparatus.