TANK OVERFLOW PROTECTION SYSTEM AND METHOD

• US 20130253857A1
• Filed: 03/23/2012
• Published: 09/26/2013
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Hershey, George
• Granted Patent: US 9,581,483 B2
• Time in Patent Office: Days
• US Class Current: 702/55
• CPC Class Codes: G01F 23/185 for discrete levels
• CPC Class Codes: G01F 23/804 containing circuits handling parameters other than liquid level

Abstract

A tank overflow protection system and method for measuring process temperature and pressure utilizing one or more piezoresistive pressure transmitters. The piezoresistive pressure transmitter includes a differential pressure sensor and a temperature sensor. Data from the piezoresistive pressure transmitters can be digitally communicated via a cable. The pressure transmitters convert signals indicative of temperature and pressure to a digital value and transmit the signals to a main processor printed wire assembly for final compensation, diagnostics, and transmission to a distributed control system. A differential pressure can be calculated by subtracting two digital pressure measurement values. The temperature measurement can be employed to calculate any changes in density for a user-defined reference value.

Claims

1. An overflow protection system for a storage tank, said system comprising:

a plurality of piezoresistive pressure transmitters, wherein each piezoresistive pressure transmitter among said plurality of piezoresistive pressure transmitters includes a differential pressure sensor and a temperature sensor;

an electronic cable for digitally and electrically communicating data to and from said plurality of piezoresistive pressure transmitters, said plurality of piezoresistive pressure transmitters capable of being connected to a top measurement point and a bottom measurement point of said storage tank in order to accurately measure process temperature and pressure data for use in preventing overflow of said storage tank; and

a processor printed wire assembly for receiving a digital signal indicative of said process temperature and pressure data from said plurality of piezoresistive pressure transmitters for compensation, diagnostics, and transmission thereof to a distributed control system.

2. The system of claim 1 wherein said processor printed wire assembly calculates differential pressure data by subtracting at least two digital pressure measurement value outputs from said differential pressure sensor.

3. The system of claim 1 wherein said processor printed wire assembly calculates a change in density with respect to a uses-defined reference value utilizing a temperature measurement value output from said temperature sensor.

4. The system of claim 1 wherein said processor printed wire assembly performs a compensation calculation with respect to a storage tank level error in said main processor printed wire assembly.

5. The system of claim 1 wherein said plurality of piezoresistive pressure transmitters and said processor printed wire assembly are separated utilizing a length of cable to maintain a transmission of pressure and temperature measurement data.

6. The system of claim 1 wherein said plurality of piezoresistive pressure transmitters comprises at least two piezoresistive pressure transmitters.

7. The system of claim 1 wherein said plurality of piezoresistive pressure transmitters comprises at least one piezoresistive pressure transmitter.

8. The system of claim 1 wherein:

said processor printed wire assembly is capable of calculating differential pressure data by subtracting at least two digital pressure measurement value outputs from said differential pressure sensor; and

said processor printed wire assembly is capable of calculating a change in density with respect to a user-defined reference value utilizing a temperature measurement value output from said temperature sensor.

9. The system of claim 8 wherein said processor printed wire assembly is capable of performing a compensation calculation with respect to a storage tank level error in said main processor printed wire assembly.

10. A method for preventing overflow of a storage tank, said method comprising:

connecting a plurality of piezoresistive pressure transmitters, wherein piezoresistive pressure transmitter among said plurality of piezoresistive pressure transmitters includes a differential pressure sensor and a temperature sensor connected to a top measurement point and a bottom measurement point of said storage tank for accurately measuring process temperature and pressure data;

calculating a differential pressure by subtracting at least two digital pressure measurement values from said differential pressure sensor utilizing a processor printed wire assembly; and

determining a change in density with respect to a user-defined reference value utilizing a temperature measurement value output from said temperature sensor by said processor printed wire assembly in order to prevent overflow of said storage tank.

11. The method of claim 10 further comprising digitally communicating data to and from said plurality of piezoresistive pressure transmitters.

12. The method of claim 10 further comprising:

converting a signal indicative of said process temperature and pressure to a digital value by said plurality of piezoresistive pressure transmitters; and

transmitting said signal to said main processor printed wire assembly for final compensation, diagnostics, and transmission to a distributed control system for controlling a level of fluid in said storage tank.

13. The method of claim 10 further comprising:

compensating a level of fluid in said storage tank with respect to an additional change due to a change in a fluid density of said fluid in said storage tank; and

performing a compensation calculation with respect to a tank level error in said main processor printed wire assembly.

14. The method of claim 10 further comprising separating said plurality of piezoresistive pressure transmitters and said processor printed wire assembly utilizing a length of said electronic cable to maintain a transmission of data indicative of pressure and temperature measurements.

15. The method of claim 10 further comprising configuring said plurality of piezoresistive pressure transmitters to comprise at least two piezoresistive pressure transmitters.

16. The method of claim 10 further comprising configuring said plurality of piezoresistive pressure transmitters to comprise at least one piezoresistive pressure transmitter.

17. An overflow protection system for a storage tank, said system comprising:

a plurality of piezoresistive pressure transmitters, wherein each piezoresistive pressure transmitter among said plurality of piezoresistive pressure transmitters includes a differential pressure sensor and a temperature sensor; and

an electronic cable for digitally and electrically communicating data to and from said plurality of piezoresistive pressure transmitters, said plurality of piezoresistive pressure transmitters capable of being connected to a top measurement point and a bottom measurement point of said storage tank in order to accurately measure process temperature and pressure data for use in preventing overflow of said storage tank.

18. The system of claim 17 further comprising a processor printed wire assembly for receiving a digital signal indicative of said process temperature and pressure data from said plurality of piezoresistive pressure transmitters for compensation, diagnostics, and transmission thereof to a distributed control system.

19. The system of claim 18 wherein said processor printed wire assembly calculates differential pressure data by subtracting at least two digital pressure measurement value outputs from said differential pressure sensor.

20. The system of claim 18 wherein said processor printed wire assembly calculates a change in density with respect to a user-defined reference value utilizing a temperature measurement value output from said temperature sensor.